Dissertations / Theses on the topic 'Social Security'

My motivation to write this thesis is based on the controversy surrounding the Social Security system that has recently infiltrated the media. Through my research, I have discovered the debate concerning Social Security is not a recent development but has existed since the 1930’s. Many sources are warning citizens to no longer count on Social Security as they most likely will not receive benefits until a extremely old age if they receive benefits at all. Current retirees are fearful of either a decrease in benefits or not receiving the money they contributed to the system through the years of employment at all. Proposals and options for overhauling the system have moved to center stage in politicians’ agendas and numbers of solutions have surfaced. Unfortunately, this debate is creating a huge divide between party lines in Congress. Some argue for more government control while others advocate privatization. The goal for this thesis is to perform a cost/benefit analysis of the two ideologies and determine which is more practical and realistic for both the government and the people.

COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Nos últimos anos no Brasil algumas modificações paramétricas foram implementadas na Previdência Social para tentar diminuir o crescente déficit entre os pagamentos de benefícios e o recebimento de contribuições. Nesse trabalho, Previdência Social é estudada sob um ponto de vista diferente: ao invés de uma análise focada apenas nos déficits atuais, utiliza-se a reserva de benefícios concedidos como uma forma de medir o impacto futuro das atuais regras de concessão de aposentadorias e pensões. Dependendo dos parâmetros utilizados, o valor da reserva supera o PIB real de 2005. O resultado também mostra que decisões sobre o aumento real do salário mínimo têm impacto bastante significativo nos gastos com benefício da Previdência Social.
In the last few years the Brazilian Government had implemented some parametrical changes to the Social Security System so to try to diminish the growing deficit in between its benefits and contribution. In this work, the Social Security is studied under a different point of view: instead of looking at nowadays deficits, the necessary reserve to benefits already under payment will be calculated, so as to measure the future impact on the political decisions which are made today. Depending on the assumed parameters, the value of this reserve can be bigger than the GDP in 2005. This result shows also how the real value increase of the minimum wage impacts significantly this reserve.

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management, 2001.
Includes bibliographical references (p. 91-92).
The Spanish public pension system is currently based on the pay as you go (PA YOO) principle. This thesis examines the current structure of this public system and its financial viability in the face of expected demographic changes. First, demographic and macroeconomic models were created extending out to 2050 and, based on them, the finances of the system were estimated assuming that the current regulations would remain largely unchanged. The simulations indicate that the system will show small surpluses for the next years followed by an alarming deterioration beyond 2020, mainly driven by demographic factors such as increasing life expectancy and the reduction in fertility rate observed in the last two decades. The baseline demographic and macroeconomic scenario results in a projected deficit of about 7% of GDP by 2045. This outlook includes a reduction of unemployment and an increase in labor force participation within reasonable limits. It is also shown that high immigration, fertility and productivity growth, again, within reasonable limits, while improving the financial outlook, do not resolve the issue. Without significant reforms, the system will be faced with a reduction in benefits and/or an increase in the payroll-tax by the second quarter of this century. The model is further used to test the effectiveness of potential reforms. We conclude that a permanent solution could be supported on three pillars: 1. The creation of a Pension Fund with the surpluses of the PAYOO system and a creative investment policy such as that recommended by Modigliani et al. 2. The contribution of the prospective surpluses from the unemployment system (INEM) to the fund during a transitory period. 3. Reforms in the pension calculating procedures that will foster participation in the labor force and eliminate some of the distortions introduced by the current system. These reforms would maintain financial viability without having to raise the payroll-tax. Furthermore, the tax could be reduced gradually beyond 2045. Additionally, this reform would combine advantages from funded pension systems, such as deepening of the capital stock and consolidation of the financial markets, with those of PAYOO schemes, such as their redistributive aspects and "defined benefit" character.
by Pedro Sainz de Baranda.
M.B.A.

Ecology – is complex problem, so complex decisions are needed. Preservation of environment and acceptance of administrative decisions, recreational use of natural resources of natural-resources fund territories demand certain regulating actions. These actions have to be based on exact basis of complex interdisciplinary approach to environment security. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/10022

Capitolo 1: Le cause del lavoro informale sono una questione dibattuta. Non è chiaro se il lavoro informale costituisca una trappola per coloro che non hanno accesso al lavoro formale, oppure se almeno in parte venga considerato un’alternativa migliore rispetto al lavoro formale. Le implicazioni di politica economica sono chiaramente diverse nei due casi. Per affrontare la questione, viene proposto un questionario per un’indagine sulle famiglie, che può essere utilizzato sia come indagine a sé stante, sia come modulo aggiuntivo per indagini esistenti, come il Living Standards Measurement Study della Banca Mondiale. Dopo la descrizione del questionario, vengono presentati i risultati di due indagini pilota, svolte in Bulgaria e in Colombia con l’obiettivo di verificare l’efficacia del questionario. Capitolo 2: In questo articolo viene studiata l’informalità, definita come evasione dei contributi pensionistici. Nel modello teorico, un lavoratore rappresentativo massimizza l’utilità intertemporale attesa, tramite la scelta ottimale della frazione di contributi da evadere, che risulta decrescente con la probabilità di sopravvivenza e con il fattore di Bismarck che caratterizza il sistema pensionistico. Tuttavia, in un’economia con agenti eterogenei, un sistema perfettamente Bismarckiano non minimizza necessariamente l’evasione contributiva. L’analisi empirica è in parte coerente con il modello teorico, anche se la relazione fra probabilità di sopravvivenza soggettiva e probabilità di evadere i contributi è negativa se si definisce l’evasione in termini di contributi per la pensione, mentre non è statisticamente significativa se si considerano i contributi per tutti i programmi del sistema di protezione sociale. Capitolo 3: Questo articolo confronta le probabilità di sopravvivenza soggettive con valori stimati ottenuti dalle tavole di mortalità, tenendo conto della riduzione nella mortalità fra generazioni. Per gli uomini, le probabilità di sopravvivenza soggettive sono superiori ma nel complesso vicine ai valori stimati dalle tavole, mentre per le donne esse sono sempre inferiori rispetto alle tavole. Le probabilità soggettive sono negativamente correlate con indicatori di problemi di salute, di vedovanza, di rischio percepito sul posto di lavoro, o di disoccupazione (per gli uomini). Esse sono invece positivamente correlate con l’età, e con indicatori di una buona opinione sulla qualità del servizio sanitario pubblico, e di soddisfazione rispetto alla sicurezza e alla stabilità del proprio lavoro. L’istruzione non sembra essere rilevante, tuttavia livelli più alti di istruzione sono associati a minori deviazioni delle probabilità soggettive rispetto ai valori stimati dalle tavole.
Chapter 1: There is a wide agreement on the fact that a large informal economy leaves many individuals without social protection and reduces government’s tax revenue and social security contributions. However, it remains an open question what really drives informality, namely whether workers are simply trapped out of the formal sector or, at least some of them, choose it because it offers better alternatives than a formal job. The policy implications are clearly different in the two cases. In order to shed light on this important issue, we propose a household survey instrument to assess the links between informality and social protection. It can be implemented either through a stand-alone survey or by adding a specific module to an existing general survey such as the World Bank’s Living Standards Measurement Study. After describing the main survey instrument, we present the results of two pilot surveys, carried out in Bulgaria and Colombia, to test the effectiveness of the questionnaire and improve its design. Chapter 2: This paper analyzes job informality, defined as the evasion of social security contributions. A representative worker maximizes expected intertemporal utility by choosing the optimal fraction of evaded taxes, which is decreasing in the survival probability and in the Bismarckian factor characterizing the pension system. However, a fully Bismarckian system does not necessarily minimize tax evasion in an economy with heterogenous agents. The empirical analysis provides some support for the theoretical model, although the relationship between subjective survival probability and probability of job informality is negative when focusing on the old age pension, but not statistically significant when considering the whole social security package. Chapter 3: This paper compares subjective survival probabilities to predictions from life-table data, taking into account the reduction in mortality across cohorts. Subjective beliefs for men are higher but reasonably close to predictions from life tables, whereas subjective probabilities for women are always lower than the prediction. Subjective probabilities are negatively related with indicators of self-reported health problems, widowhood, holding a risky job, or being an unemployed man, whereas they are positively related with age, good perceived quality of public health, and satisfaction with job security and stability. Education does not seem to matter, although higher education is associated with smaller deviations of subjective survival probabilities from life-table predictions.

The Thesis analyzes the insurance provided by pension systems against macroeconomic and demographic risks. This purpose is accomplished by simulating individual life-cycle behaviors in a steady-state partial equilibrium model with uncertainty on wages, financial market returns and life expectancy, calibrated so as to reproduce stylized facts of the Italian economy. In particular, stochastic (macroeconomic and demographic) variables, such as wages, financial market returns, social mobility and survival probabilities follow processes that have been estimated based on available data for Italy, mostly over the period 1990-2004. The Thesis is composed of three essays. The first two papers focus on comparing the insurance provided against wage-related risk by a typical Defined Benefit pension system (modeled according to the old Italian pension scheme before the 1992 Amato reform), providing benefits based on the risky wages earned in the last years before retirement on the one hand; and a typical Notional Defined Contribution system (modeled according to the new Italian pension scheme introduced by the 1995 Dini reform), providing benefits based on all working-life contributions, capitalized at a “notional” rate of return i.e. the growth rate of the economy, on the other hand. The first paper considers a model with a representative individual facing uncertainty on aggregate wages and financial market returns as well as mortality risk. The new NDC Italian pension system turns out to improve “ex-ante” individual welfare (namely, individual welfare measured at the beginning of lifetime) with respect to the old DB scheme, from a purely risk-insurance perspective. This relative gain stems from the new regime pooling a longer series of risky wages in computing benefits, thereby yielding a better wage-risk diversification which causes a reduction (in expected terms) in the variance of pensions. The second paper extends the scope of the analysis by considering a model with heterogeneous agents belonging to different social (i.e. labor-income) classes, facing uncertainty on class-specific wages and stochastic intra-generational social mobility during working life, besides riskiness related to financial market returns and life expectancy. In this setting the previous result reverses, in that the new NDC system turns out to decrease welfare in “ex-ante” terms with respect to the old DB system from a purely risk-insurance perspective, for individuals belonging to all social classes. This result is due to the fact that the new pension scheme causes a higher correlation between pensions (the social security “asset”) and working-life wages (deemed as a proxy for “human capital”), thereby increasing the overall uncertainty individuals are confronted with during their whole lifetime. Such effect prevails (therefore yielding a welfare loss) as a substantial part of the overall wage uncertainty stems from stochastic social class mobility. Generally, social security in the model (under both the old and the new system) is slightly desirable only for individuals whose labor income conditions worsen during working life, in terms of individual welfare being measured after agents discover the final social class in which they have ended up. The analysis of the third paper overall investigates the determinants of the individual choice of contributing to supplementary private pension funds, by evaluating the effects of the latest (2004) pension reform in Italy on the behavior of a representative agent facing uncertainty on aggregate wages, financial market returns and life expectancy. The 2004 reform let individuals choose between contributing to two alternative complementary schemes (each in addition to the mandatory contribution to the public social security system), namely the firm-based severance pay scheme (the so-called TFR) on the one hand, and complementary private pension funds on the other hand. Investing in pension funds turns out to be slightly welfare improving with respect to contributing to the severance pay scheme in the model. This result is uniquely due to the fact that pension funds offer a preferred risk-return combination, since individuals in the model generally turn out to prefer receiving the capitalized amount in lump-sum fashion at retirement (as under the severance pay scheme) rather than in the form of annuities from retirement onwards (as under pension funds). The preference towards lump-sum i.e. more liquid retirement assets, despite supplementary private annuities providing insurance against longevity risk (namely the risk of workers outliving their savings after retirement), is due to two main reasons: a) the pre-existence of (sizeable) public annuities, reducing the relative value of additional longevity-risk insurance from private pensions; and b) the convenience of investing considerable resources (out of a lump-sum payout) in rewarding financial markets upon retirement.
La Tesi si propone di analizzare la capacità dei sistemi pensionistici di assicurare gli individui contro rischi di natura macroeconomica e demografica. A tal fine, il lavoro effettua delle simulazioni di comportamenti individuali lungo il ciclo di vita, in un modello di equilibrio parziale in stato stazionario, caratterizzato da incertezza su salari, rendimenti finanziari e aspettativa di vita. Il modello è calibrato in modo da riprodurre fatti stilizzati dell'economia italiana. In particolare le variabili stocastiche (macroeconomiche e demografiche), quali salari, rendimenti finanziari, mobilità sociale e probabilità di sopravvivenza seguono processi stimati sulla base dei dati disponibili per il contesto socio-economico italiano, per lo più nell'arco del periodo 1990-2004. La Tesi si compone di tre saggi. I primi due lavori si prefiggono di confrontare la capacità di assicurare rischi collegati ai salari, ad opera da un lato di un tipico sistema pensionistico di tipo retributivo (di seguito nell'abbreviazione inglese DB, Defined Benefit) che eroga pensioni basate sui salari percepiti negli ultimi anni di lavoro prima del pensionamento, modellato sul sistema pensionistico italiano precedente alla riforma Amato del 1992; dall'altro lato, ad opera di un tipico sistema pensionistico contributivo a capitalizzazione figurativa dei contributi (di seguito nell'abbreviazione inglese NDC, Notional Defined Contribution) che eroga pensioni basate sui contributi versati nel corso dell'intera vita lavorativa e capitalizzati ad un tasso figurativo (“notional”) quale il tasso medio di crescita dell'economia, modellato sul nuovo sistema pensionistico italiano introdotto dalla riforma Dini nel 1995. Il primo lavoro considera un modello con un agente rappresentativo, soggetto a incertezza su salari aggregati e rendimenti finanziari nonché al rischio di mortalità. Il nuovo sistema pensionistico italiano di tipo NDC risulta migliorare il benessere individuale “ex-ante” (ossia, il benessere individuale misurato all'inizio della vita economica) rispetto al precedente sistema di tipo DB, in termini puramente assicurativi. Questo guadagno deriva dal fatto che il nuovo regime pensionistico, nel calcolo delle pensioni, aggrega (in “pooling”) una serie più estesa di salari rischiosi, determinando in tal modo una migliore diversificazione del rischio sui salari, che causa una riduzione in termini attesi nella varianza delle pensioni stesse. Il secondo lavoro estende la portata della precedente analisi considerando un modello con agenti eterogenei appartenenti a diverse classi sociali (ossia, a diverse classi di reddito lavorativo), soggetti a incertezza sia sui salari specifici di ciascuna classe sia sulla mobilità sociale (stocastica) intra-generazionale durante la vita lavorativa, oltre che alla rischiosità dei rendimenti finanziari e dell'aspettativa di vita. In questo scenario il precedente risultato si ribalta, in quanto il nuovo sistema NDC risulta peggiorare il benessere “ex-ante” rispetto al precedente sistema DB in termini puramente assicurativi, per individui appartenenti a tutte le classi sociali. Questo risultato è dovuto al fatto che il nuovo schema pensionistico comporta una più alta correlazione tra pensioni (“asset” previdenziale) e salari percepiti nel corso dell'intera vita lavorativa (considerati come proxy per il “capitale umano” individuale), in tal modo aumentando la quantità complessiva di incertezza cui gli individui sono soggetti nel corso della loro intera vita, e questo effetto prevale (causando una perdita di benessere) quando gran parte dell'incertezza salariale è legata alla mobilità sociale stocastica intra-generazionale. In generale, il sistema previdenziale nel modello (sia del tipo DB che del nuovo tipo NDC) risulta leggermente desiderabile esclusivamente per gli individui le cui condizioni reddituali peggiorano durante la vita lavorativa, in termini di benessere individuale misurato dopo che gli agenti hanno scoperto la classe sociale finale cui si trovano ad appartenere. L'analisi del terzo lavoro è complessivamente volta ad investigare le determinanti della scelta individuale di contribuire a forme di previdenza privata complementare, attraverso la valutazione degli effetti dell'ultima riforma previdenziale in Italia (2004) sul comportamento di un agente rappresentativo soggetto a incertezza su salari aggregati, rendimenti finanziari e aspettativa di vita. La suddetta riforma permette agli individui di scegliere tra due schemi alternativi a cui versare contributi (obbligatori), in aggiunta ai contributi per il sistema pensionistico pubblico, ossia lo schema del Trattamento di Fine Rapporto da un lato, e i fondi pensione complementari dall’altro. Investire nei fondi pensione risulta aumentare leggermente il benessere degli individui nel modello, rispetto alla scelta di contribuire allo schema del TFR. Questo esito è dovuto unicamente al fatto che i fondi pensione offrono una migliore combinazione rischio-rendimento, poiché gli individui nel modello preferiscono in generale ricevere il capitale accumulato in somma fissa al pensionamento (come accade nel caso del TFR) piuttosto che sotto forma di rendita dal pensionamento in avanti (come accade nel caso dei fondi pensione). Questa preferenza per il versamento in un'unica soluzione, ossia per forme più liquide di risparmio previdenziale privato, nonostante pensioni erogate sotto forma di rendita forniscano assicurazione contro il rischio di longevità (ossia il rischio che un lavoratore viva più a lungo di quanto atteso, e quindi si ritrovi con insufficienti risorse risparmiate per gli ultimi anni di vita), è dovuta a due motivi principali: a) la pre-esistenza di (cospicue) rendite pensionistiche pubbliche, che riduce il valore relativo dell'assicurazione aggiuntiva fornita da rendite private; b) la convenienza relativa di investire, al momento del pensionamento, nei mercati finanziari ad alto rendimento atteso una quota consistente delle risorse ricevute in somma fissa.

Thesis (Ph. D.)--University of Sydney, 2002.
Title from title screen (viewed Apr. 24, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Social Work, Social Policy & Sociology, Faculty of Arts. Includes bibliography. Also available in print form.

More firms outsource information technology (IT) security activities each year, as they determine that they can achieve cost savings or a higher level of security at the same cost. However, despite the estimated benefits, many firms still fail to see a clear positive net benefit from their (private) perspective, given the risks and costs involved. This paper investigates the positive externalities associated with IT security outsourcing. My research suggests that, when one organization decides to outsource its security, both direct and indirect benefits can accrue to other organizations and users. In this paper I analyze how a variety of decision characteristics affect whether and to what level such positive externalities will result. I also discuss implications for public policy and for firm-level decision making.

O objetivo desta pesquisa é identificar um conjunto de fatores que exerce influência no resultado financeiro e nos componentes de receitas e benefícios previdenciários do Regime Geral de Previdência Social (RGPS). Para isso, foi feita uma revisão da literatura especializada à procura de referências aos fatores. De posse da relação de fatores citados pelos especialistas no tema, foram selecionados indicadores para representá-los. Em seguida, foram obtidos os dados constituídos por séries temporais dos indicadores. Esses dados foram submetidos ao método de análise de regressão múltipla aplicada à luz do referencial teórico da econometria de séries temporais. Os resultados confirmam a influência dos fatores demográficos, salário mínimo, rendimentos, trabalho informal e desemprego nas receitas, benefícios e resultado financeiro do RGPS.
The objective of this study is to identify a set of factors that explains the financial results of the General Regime of Social Security (GRSS) in Brazil, including the components of revenues and benefits. To achieve this objective, specialized literature was consulted and the factors referred were listed. For each factor, one indicator was selected to represent it and the time series of indicators values were obtained. In the next phase, the time series were submitted to the multiple regression analysis method, implemented according to the assumptions of econometrics. The results confirmed the influence of demographic factors, minimum salary, wage, informal work and unemployment on revenues, benefits and the global financial result of the GRSS.

In the last decade, without any doubt, social media i.e. social network platforms that are mainly created in order to interact with each other such as Facebook, Twitter, LinkedIn, Google +, Tumblr, Instagram, Flickr, Myspace, Blogs, YouTube, or any user generated content websites gained huge access in public daily life including individuals and organizations. These social network platforms, especially Facebook, Twitter, YouTube, were grown in such fast pace manner that even the big companies including Microsoft, Google, etc. has changed their strategies, and adapted social network platforms very well. That was the time when people, and small organizations who did not have platform for user generated content, had to pay fee to upload their content over Internet. Most of small companies were using privately purchased platform to distribute and share their content; whereas, individuals were limited to post their contents; Emails & IMs were used frequently to share their text, pictures, videos, etc. By the year 2004, freely/ free social network platforms became so common/easy to use and were hugely successful. Platforms were able to provide users to share content quite easily. Small businesses started using social network to promote their business. Veterans were easily connected with their users & followers to provide help & information they are looking for. Upon such rapid growth of these social media platforms; benefits, rewards & opportunities are uncountable, however, it also came with risks and security issues. This research is limited, however it provides valuable information presented in scientific articles in digital libraries. There was total of 214 articles found related to research topic. By refining results, number of articles were reduced to 30 which were selected for actual research using SLR steps. The results were summarized in tabular format and answers the research question in discussion chapter which can be helpful to existing social network platforms, their operators and users.

Mestrado em Línguas e Relações Empresariais
A cultura organizacional é algo imaterial, intangível mas percetível através dos seus efeitos e consequências. Uma organização pode ser comparada a um indivíduo como possuidor de uma identidade, única e irrepetível. Com este trabalho pretende-se estudar o impacto da empresa Bosch, Security Systems no concelho de Ovar, a partir do início das suas atividades até à atualidade. Isto, com o objetivo de perceber se a implementação provocou modificações ao integrar-se no concelho. A partir das análises dos indicadores sociais e económicos, da realização de entrevistas procurou-se demonstrar que o concelho tem sofrido alterações com a implementação de empresas internacionais ao longo do tempo.
The organizational culture is something immaterial, intangible but perceptible through its effects and consequences. An organization can be compared to an individual as possessor of an identity, unique and unrepeatable. We intend to study the impact of the company Bosch, Security Systems in the Ovar municipality. From the start of its activities to the present time. This, in order to understand if the implementation has caused regarding its integration. Starting from the analyses of social and economic indicators, and the realization of interviews we intend to demonstrate that the municipality has improved positive consequences with the implementation of international companies in its area along the time.

The U.S. social security system faces funding pressure due to the aging of the population. This dissertation examines the welfare cost of social security reform and social security policy uncertainty under rational expectations and under learning. I provide an overview of the U.S. social security system in Chapter I. In Chapter II, I construct an analytically tractable two-period OLG model with capital, social security, and endogenous government debt. I demonstrate the existence of steady states depends on social security parameters. I demonstrate a saddle-node bifurcation of steady states numerically, and demonstrate a transcritical bifurcation analytically. I show that if a proposed social security reform is large enough, or if the probability of reform is high enough, the economy will converge to a steady state. In Chapter III, I develop a three-period lifecycle model. The model is inherently forward looking, which allows for more interesting policy analysis. With three periods, the young worker's saving-consumption decision depends on her expectation of future capital. This forward looking allows analysis of multi-period uncertainty. Analysis in the three-period model suggests that policy uncertainty may have lasting consequences, even after reform is enacted. In Chapter IV, I develop two theories of bounded rationality called life-cycle horizon learning and finite horizon life-cycle learning. In both models, agents use adaptive expectations to forecast future aggregates, such as wages and interest rates. This adaptive learning feature introduces cyclical dynamics along a transition path, which magnify the welfare cost of changes in policy and policy uncertainty. I model policy uncertainty as a stochastic process in which reform takes place in one of two periods as either a benefit cut or a tax increase. I find the welfare cost of this policy uncertainty is less than 0.25% of period consumption in a standard, rational expectations framework. The welfare cost of policy uncertainty is larger in the learning models; the worst-off cohort in the life-cycle horizon learning model would be willing to give up 1.98% of period consumption to avoid policy uncertainty.

Thesis (MA)--Stellenbosch University, 2001.
ENGLISH ABSTRACT: This thesis focuses on the extent to which the South African social security system succeeds in providing protection in the vulnerable periods of the life-cycle and against the major contingencies of unemployment, disability and disease. Through a detailed examination of the different social insurance and assistance programmes, it isolates which particular population segments (by occupation, income quintile and race group) "fall through the cracks" in the provision of income security. It does not look only at the articulation between different social insurance and social assistance programmes, but also acknowledges how social security complements other governmental interventions, such as social services, and non-state sources of income security, such as those provided by the private insurance market and the family and community. Part One of the thesis is devoted to an examination of social insurance in South Africa, in other words, to those programmes that seek to compensate for a loss of income in the event of particular contingencies and that are funded by contributions from employers and employees. In addition, theoretical perspectives on social security, and social insurance in particular, are provided, with a discussion of the various economic arguments in favour of and against the provision of social security. Part Two of the thesis examines the range of non-contributory social assistance - cash benefits paid form general revenue - that are available to South Africans who qualify in terms of the means tests. Each chapter provides an analysis of the extent to which the social assistance programme under analysis provides a safety net for the relevant category of vulnerable people. It does this by examining the appropriateness of the programme structure, take-up rates and the fiscal sustainability of the programmes. In addition, the budgetary process by which revenue is allocated to social assistance programmes and expenditure trends are examined. The thesis concludes that although the South African social security system has achieved a fairly advanced level of development and covers a fairly wide range of risks, there are a number of constraints facing its further expansion. Social insurance schemes provide generous benefits, but their membership is restricted to the employed. Expanding coverage by social insurance would require substantial growth in remunerative employment which, given prevailing labour market conditions, seems unlikely. The provision of more generous social assistance programmes catering for a broader range of contingencies is severely curtailed by already high fiscal expenditure on welfare and macroeconomic constraints. Moreover, changing demography, household structures and dependency burdens, especially as the HIV/AIDS epidemic spreads, seem likely to increase demands on social assistance programmes. Consequently, until employment can be expanded so that more people can contribute to their own income security, the informal social security provided by the family and/or community will remain the first line of support for many.
AFRIKAANSE OPSOMMING: In hierdie tesis word gefokus op die mate waartoe die Suid-Afrikaanse bestaansbeveiligingstelsel daarin slaag om ondersteuning tydens kwesbare periodes in die lewensiklus en beskerming teen groot gebeurlikhede soos werkloosheid, ongeskiktheid of langdurige siekte te bied. Daardie bevolkingsegmente (volgens beroep, inkomstegroep of ras) wat nie volledig toegang tot inkomstesekuriteit het nie, word uitgesonder deur 'n gedetaileerde ondersoek van die verskillende maatskaplike versekerings- en bystandsprogramme. Daar word ook gekyk na die artikulasie tussen die verskillende programme sowel as na hoe ander regeringsintervensies (bv. verskaffing van maatskaplike dienste) en private bronne van inkomstesekuriteit - verskaf deur die privaat versekeringsmark, die gemeenskap en die familie - deur maatskaplike bystand aangevul word. Deel Een word gewyaan 'n ondersoek van maatskaplike versekering in Suid-Afrika - daardie programme wat vir inkomsteverlies weens spesifieke gebeurlikhede probeer kompenseer en wat tipies deur bydraes van werkgewers en werknemers befonds word. Teoretiese perspektiewe op bestaansbeveiliging in die algemeen en maatskaplike versekering in besonder word ook verskaf en argumente vir en teen die verskaffing van bestaansbeveiliging word bespreek. Deel Twee ondersoek die reeks nie-bydraende bestaansbeveiligingsprogramme wat uit algemene owerheidsinkomste befonds word, asook bestedingstendense in maatskaplike bystand. Die tesis kom tot die gevolgtrekking dat, alhoewel Suid-Afrikaanse bestaansbeveiliging 'n redelik gevorderde vlak van ontwikkeling bereik het en 'n wye reeks risiko's dek, daar 'n aantal beperkinge op verdere uitbreiding is. Maatskaplike versekeringskemas bied uitgebreide voordele, maar lidmaatskap is tot indiensgeneemdes beperk. Uitbreiding van dekking vereis beduidende groei in formele indiensneming, wat onwaarskynlik lyk, gegewe huidige arbeidsmarktendense. Die verskaffing van gunstiger maatskaplike bystandsprogramme gemik op meer gebeurlikhede word ernstig deur reeds hoë fiskale uitgawes op welsyn en deur makroekonomiese oorweginge beperk. Verder sal veranderende demografiese strukture, huishoudingstrukture en afhanklikheidslaste, veral teen die agtergrond van die toename in HIVNIGS, aansprake op maatskaplike bystandsprogramme vergroot. Gevolglik sal die informele inkomstesekuriteit gebied deur die familie en/of gemeenskap die eerste of enigste ondersteuning vir groot dele van die bevolking bly, totdat indiensneming genoeg uitgebrei kan word sodat meer mense tot hul eie inkomstesekuriteit kan bydra.

This thesis contributes to the literature seeking to reconceptualise human security from a critical feminist perspective. It argues that security is a field of power, implicated in context-specific ways in the (re)production of gendered violences, and that human security must account for how such violences are (re)produced in and through the everyday. It explores how socially and historically embedded security institutions, discourses and practices are implicated in ‘the (violent) reproduction of gender’ (Shepherd 2008), taking as a case study Delhi Police’s initiatives to address violence/crime against women, in response to the city’s notoriety as India’s ‘rape capital’. Drawing on 86 in-depth interviews and 6 months of observational fieldwork with Delhi Police, the thesis shows that Delhi Police have found innovative ways of doing ‘security’ which depart from its association with (masculinist) authority and protection, and which apprehend violences embedded in the everyday. However, the effects are contradictory and ambivalent. Despite challenging some aspects of gender relations, the policing of violence/crime against women also reproduces conditions which enable and sustain the violence. The thesis explores how police discourses construct violence in terms of vulnerability and responsibility, in ways which both normalise and exceptionalise certain violences, and map gendered safety onto normative ideas of sexual integrity such as to reproduce the heteronormativity of marriage as a compulsory institution for women. It investigates the spatial and temporal distancing through which violence/crime against women is constructed, and the consequent reproduction of class differentiation and identification, and normative gender and sexuality. It considers how the unstable gendering of policing, and police work, intersects with and contributes to such constructions of violence/crime against women, and their discursive effects. The thesis concludes with a qualified and partial recuperation of human security as emancipatory – where emancipation is conceived as transforming oppressive power relations, and power is understood in a Foucauldian sense as pervasive, unstable and productive. It highlights the limits of security, and the relativity of its achievability.

The purpose of this thesis is to counterargue Simon Dalby’s claim that the national security perspective should be replaced by a global security perspective. Dalby argues that the national security is inappropriate to capture the current issues regarding the environmental security. To counterargue Dalby’s claim, I represent the national security perspective by using the perspective of states’ energy security, and compare current trends and issues regarding states’ energy security and the environmental security. This is done to argue that states can either chose to enhance their own energy security or the environmental security. Prisoners' Dilemma is then used as a theoretical framework on an explanatory example to provide insights about a dilemma, called the Energy- Environment Dilemma in this thesis, that curbs states’ ability to commit themselves to the cause of protecting the environmental security. The explanatory example used is the strategic importance of the Northwest passage for the U.S. and Canada. The results of this thesis suggests that the national security perspective, in combination with Prisoners’ Dilemma, is useful to provide insights about the Energy-Environmental Dilemma. Replacing it with a global security perspective would be to ignore a perspective which can provide insights about a challenge for states to commit to the cause of protecting the environmental security.

¿Porqué existen programas de seguridad social que transfieren recursos desde los trabajadores a los mayores? (ii) ¿Porqué los programas de seguridad social preveen que para cobrar la pensión los trabajadores tienen que jubilarse? (iii) ¿Cuál es el impacto del proceso de envejecimiento de la población sobre la jubilación y la seguridad social? (iv) ¿Cuál es la evidencia empírica sobre la importancia de la finámica demográfica como determinante de la jubilación y de la seguridad social en el mundo? Esta tesis contribuye a contestar a estas preguntas en un contexto político-económico. Primero, examina el estado del arte, y las principales contribuciones en la literatura de los modelos político-económico de la seguridad social. Segundo, considera los elementos políticos que relacionan la seguridad social con la jubilación, desarrollando un modelo de votación`probabilística. Una hipótesis crucial es que el tiempo libre en la edad mayor representa un "merit good", es decir un bien que tiene valor positivo para todos los agentes en la sociedad (jóvenes y viejos). En consecuencia, los jóvenes inducen los políticos a establecer un impuesto positivo sobre la renta laboral de los viejos, que los induce a retirarse. Esto aumenta el nivel de homogeneidad ideológica de los viejos, y por lo tanto su poder político para obtener una transferencia desde los jóvenes. Tercero, la tesis examina el nivel de equilibrio de jubilación y de seguridad social en un contexto económico y demográfico, desarrollando un modelo a generaciones solapadas con grupos de interés. El modelo estudia la solución política que sandrá cuando la proporción de viejos en la población aumentará. Cuarto, la tesis ofrece nuevas evidencias sobre los determinantes del nivel de jubilación y de seguridad social en el mundo, construyendo un nuevo data set que incluye las informaciones sobre demografía, jubilación y seguridad social para muchos paises.

This paper opens a series of discussion papers which report about the findings of a research project within the Phare-ACE Programme of the European Union. We, a group of Bulgarian, German, Greek, Polish and Scottish economists and agricultural economists, undertake this research to provide An Integrated Analysis of Industrial Policies and Social Security Systems in Countries in Transition.1 This paper outlines the basic motivation for such study.

The purpose of this paper is to re-estimate the impact of Social Security on aggregate private saving behavior by using new time series data for the period 1947 through 1993. The analysis is based on the life-cycle hypothesis developed by Modigliani and Ando. Feldstein's extended life-cycle model, incorporating Social Security Wealth (SSW) into the traditional life-cycle model, provides the building block for this paper. A Generalized Least Squares (GLS) procedure is used to perform the time series analysis in order to avoid autocorrelation, which is usually associated with the Ordinary Least Squares (OLS) procedure. Compared with OLS estimations, the results from the GLS procedure do not indicate a large divergence regarding the statistical significance of the coefficient of SSW as well as those of other variables included except the smaller estimated parameter values. The major finding in this paper is that SSW does depress potential personal and private saving. The result support Feldstein's 1974 findings, but the magnitude of the coefficient of SSW is smaller. Feldstein's estimations, by using OLS, indicated that SSW reduced potential personal saving by 50% and induced total private saving to decrease by 38%. Our estimates imply that SSW reduces personal and private savings by 44% and 13% , respectively. The most important finding in this paper is that if SSW reduces total private saving by 13%), in the long run the decrease in the rate of private saving would also depress the private capital stock by 13%, which implies a substantial reduction in GDP and a lower level of real income.

The inclusion of the right of access to social security in the Constitution did not meet with wholehearted approval in South Africa. This right, however, is of vital importance for the future upliftment of the country. The present social security system is based upon a clear distinction between social assistance and social insurance. There is a gap in current social security provisions in that the unemployed middle aged individual is not covered. Unemployment itself is one of the greatest challenges obscuring the implementation of a comprehensive social security system. The Constitutional right is to have ‘access’ to social security and the amount of resources at the state’s disposal is directly related to increasing this right, although it is true that a number of available resources are misspent. The state must take reasonable legislative and other measures, within its available resources, to achieve the progressive realisation of the right of access to social security. The principles of solidarity and ubuntu must be cultivated so that national social development becomes a concern for all citizens. There are numerous problems facing South Africans in attaining the goal of access to social security – even if national social development does become a priority. Budgetary constraints, poverty, unemployment, HIV/Aids and foreigners are examples of these. By making social security a priority for everyone, existing ideas (almost all of which have merit) may be converted into long-term solutions for poverty and unemployment. Currently, numerous opportunities to salvage the situation are being overlooked as a result of the lack of a comprehensive and structured plan to better the access to social security. The constitutional right of access to social security is enforceable, although the jurisprudence in this field remains underdeveloped. Conditions are currently favourable, within the country and beyond its borders, for an imaginative and concerted attempt to be made to find potential solutions. It is possible for resources to be increased and for tax benefits to be incorporated for businesses which have the capacity to contribute. The issue of defence spending is controversial, but could hold the key to lowering unemployment. Should jobs be created, it is likely that they will initially be of a temporary nature. Consequently, provisions are needed to ensure some guarantee of income in the lacuna between when a job is lost and another found. Ultimately, one thing is certain: the constitutional right of access to social security will only be complete once the people who are recipients of this right make sacrifices and create corresponding duties for themselves to ensure that the next generation of inhabitants of this country are not facing similar problems. The state’s goal should be to ensure that the basic rights which all people enjoy in terms of the Constitution (in particular the other socio-economic rights) are guaranteed for the duration of their existence, even if the level of benefits received by such people is low.

Less than 30 per cent of the world’s population is covered by some form of modern social security scheme. In the African continent the coverage in some places is well below 10% of the population. Tanzania and its East African neighbours Kenya, Uganda, Rwanda and Burundi are no exception. This research explores the factors that restrict the widening of social security coverage in Tanzania and discusses whether or not lack of effective communication is a contributing factor. In Tanzania, traditionally societies are known to have practiced some form of social insurance within specific communities including tribe, clan, and extended family. This study examines whether there has been a shift of attitudes from traditional social security towards modern social insurance arrangements It also explores the types of communication that are taking place and suggests ways in which such communication can be improved for more effective results. Furthermore the study evaluates awareness and level of understanding of the public regarding modern social security schemes. It measures acceptability and willingness of people to learn about the schemes and it explores the factors that hinder participation. Grunig J. (1992) and other authors from the developed world have suggested concepts of excellent communication including two way asymmetrical and symmetrical approaches. This study looks at the application of these approaches in Tanzania. Surveys were conducted in nine regions involving workers from both formal employment and the informal sector: fishing, mining, farming, livestock keeping, small scale business and other self-employed personnel. The need to investigate the informal sector comes from the fact that more than 80% of the active labour force make their living through such ventures. Finalist students from A level secondary schools and teacher training colleges were investigated as these are just about to enter the employment market and could share their knowledge and experience as dependents. Interviews were conducted with stakeholders within the insurance industry itself including service provider institutions in Tanzania, the retirees, academicians, aged group associations, the unemployed, communication practitioners and members of the public. These were recorded and for those who did not wish to be recorded, notes were taken. For quantitative data SPSS and STATA software were utilized while NVivo and ATLAS were deployed as tools for qualitative data analysis. More qualitative data were obtained through secondary sources and interviews conducted in Burundi and Uganda. The aim was to establish if there were any similarities in social security coverage and its communication aspects with cross border neighbours. Modern communication theory (Grunig and Hunt, 1984) emphasizes a two-way rather than a one-way relationship between an organisation and its stakeholders. The subject of symmetrical and asymmetrical communication is addressed with regard to establishing the type of communication taking place and suitability of the same. Other theories related to effective communication are examined. These include diffusion of innovation theory and mass communication. The practices of social security schemes in Tanzania appear to show that there is a need to apply a tailor made communication approach to fit local realities. The study establishes that modern life challenges coupled with the effects of globalisation have eroded the value and practicability of traditional social security. Hence, societies have sought for an alternative solution but most people do not look at modern social security providers as their way forward. The survey has established that only about 20% of the population accepts modern social security systems. Moreover the communication approaches used by the main service providers are mainly tactical as they do not go deep enough to address the information needs. In addition, the level of interaction required between the service providers and their potential clients is insufficient. Social security institutions carry the image of being huge financial institutions, donating and participating in a wide range of social activities. On the contrary, however, they do not seem to play an active part in assisting their contributors who have lost employment. In this regard the institutions fail to demonstrate care beyond paying the basic entitlement. The present research found a lack of savings culture, a low degree of risk appreciation, and the common belief that when faced with social and economic contingencies, society in general, family members, or one’s own assets would come to the rescue. Most of these shortfalls could be addressed with the application of effective communication strategies including conduct of a public communication campaign that includes a special national campaign. The findings have also established that low income, fragmentation of the schemes, unattractive benefit packaging, unfriendly restrictions and corruption have had an impact on the low coverage. Finally, there are suggestions regarding the need to adopt a more suitable communication frame work that could be applied in addressing the deficiencies uncovered during the study. This should make a substantial difference.

Since social security involves several individual parameters, in recent years considerable attention has been focused on the impact these parameters on pension and social security systems. The literature on pensions has long been highlighting concerns that public Pay-As-You-Go (PAYGO) pension systems will turn out to be unsustainable in the long run and are a concern for most countries around the world, from the industrialised nations to the developing countries. The common trend in responses to what is a pensions crisis is a wave of parametric pension adjustments during the last years. These parametric reforms include, among others, changes in the contribution ceilings, increases in the retirement age, reductions in the indexation of pensions or even carrying out a structural reform from a Defined Benefit pension system to a Notional Defined Contribution (NDC). Following this process of reforming the pension system, this thesis is focused on the most important innovation in public pension schemes over the past years, first on Actuarial Balancing Mechanism (ABM) in PAYGO and second in some aspects of the Notional Defined Contributions, both in a deterministic framework. The ABM mechanism, that uses non-linear optimization models, identifies and applies an optimal path of these variables into a PAYGO system and absorbs fluctuations in longevity, fertility rates, life expectancy or any other events in a pension system. For the NDC, the Survivor Dividend (SD), also called inheritance gains, kept by most NDCs is analysed under different assumptions to calculate the maximum mortality decrease a scheme can cover if the SD is not distributed and whether the SD is a potential solution to cover the longevity. The research has considerable potential impact. It addresses a clear need in political, business, economic and societal contexts. This project also bridges the gap between academics and policy makers for better pension's public policies under alternative financial and economic scenarios. As a result, it will allow to design and assess the path of reforms in a more efficient manner. Further development will include a stochastic framework, considering stochastic dynamic programming, robustness, sensitivity analysis and error bounds.

Mestrado em Finanças
Apesar da existência de diferentes estudos sobre a economia paralela, a literatura dedicada ao estudo da relação entre esta e os sistemas de segurança social é praticamente inexistente, o que pode ser, de certa forma, explicado pela sua difícil medição e incerteza do seu impacto. Como tal, este estudo pretende explorar a relação entre a economia paralela e o sistema de segurança social português, abordando as mútuas influências e as consequências que daí possam advir. Utilizando dados do período 1983-2015, foi construído um modelo econométrico que relaciona o tamanho da economia paralela com os gastos da segurança social. De acordo com este estudo foi possível concluir que existe evidência estatística para se poder afirmar que em Portugal, durante o período em análise, um aumento dos gastos da segurança social exerceu um impacto negativo no tamanho da economia paralela.
Despite the existence of many studies regarding shadow economy, literature dedicated to study the relation between it and social security systems is almost inexistent, partly explained by the hard measurement of the former one and the uncertainty of its impact. Thus, this study intends to explore the relation between shadow economy and the Portuguese social security system, discussing what kind of influence they can have on each other and what consequences arise from it. Using data from 1983 to 2015, an econometric model that relates shadow economy size with social security expenditure was built. From this study, it was possible to conclude that there is statistical evidence to affirm that in Portugal, during this period, a growth of social security expenditure exerted a negative impact in the shadow economy size.
info:eu-repo/semantics/publishedVersion

Mestrado em Ciências Actuariais
This thesis examines the Malawi pension fund reform using an integrated simulation model. The aim is to explore why the Malawi government moved from Pay as you go (PAYG) system to define contribution (DC) system. Malawi is a relatively young country and its pension schemes are deficient in design, financing, execution and administration. Malawi has persistent macroeconomic fluctuations and an unstable financial sector that make effective pension fund management challenging. Also there are high inflation rates and politically motivated low-yield investment loans. The thesis assumes that in Malawi an average person retires by 50 years and the maximum age of death is 70. The average starting wage ranges from 65,000-75,000 Mk. The contribution rate is 15% of payroll with a transaction cost of 5% of wages. The common investment strategy is a 50-50-0-0-0 approach, i.e. 50% of assets are allocated to bank deposits and government bonds respectively. In addition a risk return analysis is employed to test the portfolio riskiness. The test include the Sharpe ratio, the Jensen measure and the Treynor measure. It was observed following the simulation tests that replacement rates are higher when retirement age rises to 60 or 65, but retiring at 50 had very low replacement rates. Meaning, pensioner can get favourable retirement income when he/she retires at 65 but this is a problem since life expectancy is 54 years. The portfolio risk test indicated very low results meaning low risks. This is as a result of allocating the funds in less risky assets i.e. government bonds which have low investments yield trickling down to low pensions. To improve the current pension system, Malawi needs to redesign its pension system to tackle the life expectancy problem, diversify pension fund portfolios to achieve a high and stable return, and invest in the economy in order to have a stable macro-economy that can protect the real value of pension assets.
Esta tese examina o fundo de pensão de reforma do Malawi usando um modelo de simulação integrada. O objetivo é explorar por que o governo do Malawi passou do sistema Pay as you go (repartição ) para um sistema de contribuição definida (capitalização). Malawi é um país relativamente jovem e os seus regimes de pensões são deficientes em design, financiamentos, execução e administração. Malawi tem flutuações macroeconômicas persistentes e um sector financeiro instável que fazem a gestão eficaz de fundos de pensões desafiante. Além disso, existem altas taxas de inflação e politicamente motivadas empréstimos de investimento de baixo rendimento. A tese parte do princípio de que no Malawi uma pessoa média se aposenta aos 50 anos e de que a idade máxima de morte é de 70 . O salário médio inicial varia de 65,000-75,000 Mk. A taxa de contribuição é de 15% do salário, com um custo de transação de 5% dos salários. A estratégia comum de investimento é uma abordagem 50-50-0-0-0 , ou seja, 50% dos activos são alocados para os depósitos bancários e títulos do governo, respetivamente. Além disso, uma análise de retorno de risco é utilizada para testar o grau de risco da carteira. O teste inclui o índice de Sharpe, a medida Jensen e a medida Treynor. Observou-se nos ensaios de simulação que as taxas de substituição são mais elevados quando a idade da reforma sobe para 60 ou 65 anos, mas se a reforma for aos 50 anos obtêm-se taxas de substituição muito baixas. Ou seja, o pensionista pode obter uma pensão favorável quando se aposenta aos 65 anos , mas existe um problema, já que a expectativa média de vida é de 54 anos. O teste de risco da carteira dá resultados muito baixos indicando baixo risco. Este é o resultado da alocação dos recursos em ativos de menor risco, ou seja, títulos do governo, produzindo pensões baixas. Para melhorar o actual sistema de pensões, Malawi precisa redesenhar o seu sistema de pensões para enfrentar o problema da expectativa de vida, diversificar carteiras dos fundos de pensões para conseguir um retorno alto e estável, e investir na economia, a fim de ter uma macroeconomia estável, que pode proteger o valor real dos ativos de pensões.

У тезах доповідей досліджується вплив соціальних факторів на розвиток регіону. Зазначається про важливість долучення кожного суб'єкта, що діє в регіоні, до здійснення соціального впливу, що забезпечить усебічність підтримки системи соціального забезпечення кожної місцевої громади.
В тезисах доклада исследуется влияние социальных факторов на развитие региона. Отмечается важность каждого субъекта, который действует в регионе, в осуществлении социального влияния, что может обеспечить всестороннюю поддержку системы социального обеспечения каждой местной громады.
The author investigated the influence of social factors on the region development. It is noted the importance of the adding of each entity of the region to the implementation of social impact, providing circumstantiality support for social security system of each local community.

This research examines the attitude that Zimbabwe portrays towards the protection, promotion and enforcement of the right to social security. Zimbabwe did not have a Constitution that provided for the realisation of the right to social security before 2013. With the enactment of the 2013 Constitution, many people now have a chance to enjoy economic, social and cultural rights (including social security) which ordinarily was not possible in the past. Provision of the right to social security plays a pivotal role by assuring human dignity for people when they are faced with circumstances such as the deteriorating and unpredictable economic situation in Zimbabwe in recent years. This study uses academic textbooks, journals, legislation, international treaties, newspaper reports and other sources of literature to analyse Zimbabwe’s outlook on social security and examines the structures, policies and institutions put in place to enforce the right to social security. The Constitutional provisions for social security are also analysed in the light of international instruments’ provisions of social security to find out if they are adequate and effective in the protection and promotion of social security in Zimbabwe. The study also examines the national polices; the national commission for human rights and the courts to determine their efficacy in their administration of the right to social security. The Constitution of Zimbabwe states that when provisions of the declaration of rights and any legislation such as the provisions for the right to social security are being interpreted, international law and all treaties and conventions that Zimbabwe is a party to must be taken into consideration. Thus, in this study the application and influence on the enforcement of the right to social security by international law and all the treaties and conventions that Zimbabwe is a party to, are scrutinised. Budgets mirror the government’s values and can be reflective of the attitude that a State has towards a priority. That is why the study also examines the budget allocation and spending patterns of Zimbabwe towards the protection and promotion of the right to social security.
Mini Dissertation (LLM)--University of Pretoria, 2019.
Public Law
LLM (Socio-Economic Rights)
Unrestricted

Thesis (Ph.D.)--Indiana University, Dept. of Economics, 2008.
Title from PDF t.p. (viewed on Jul 28, 2009). Source: Dissertation Abstracts International, Volume: 69-12, Section: A, page: 4811. Adviser: Gerhard Glomm.

Online social networks (OSNs) have gained soaring popularity and are among the most popular sites on the Web. With OSNs, users around the world establish and strengthen connections by sharing thoughts, activities, photos, locations, and other personal information. However, the immense popularity of OSNs also raises significant security and privacy concerns. Storing millions of users' private information and their social connections, OSNs are susceptible to becoming the target of various attacks. In addition, user privacy will be compromised if the private data collected by OSNs are abused, inadvertently leaked, or under the control of adversaries. as a result, the tension between the value of joining OSNs and the security and privacy risks is rising.;To make OSNs more secure and privacy-preserving, our work follow a bottom-up approach. OSNs are composed of three components, the infrastructure layer, the function layer, and the user data stored on OSNs. For each component of OSNs, in this dissertation, we analyze and address a representative security/privacy issue. Starting from the infrastructure layer of OSNs, we first consider how to improve the reliability of OSN infrastructures, and we propose Fast Mencius, a crash-fault tolerant state machine replication protocol that has low latency and high throughput in wide-area networks. For the function layer of OSNs, we investigate how to prevent the functioning of OSNs from being disturbed by adversaries, and we propose SybilDefender, a centralized sybil defense scheme that can effectively detect sybil nodes by analyzing social network topologies. Finally, we study how to protect user privacy on OSNs, and we propose two schemes. MobiShare is a privacy-preserving location-sharing scheme designed for location-based OSNs (LBSNs), which supports sharing locations between both friends and strangers. LBSNSim is a trace-driven LBSN model that can generate synthetic LBSN datasets used in place of real datasets. Combining our work contributes to improving security and privacy in OSNs.

Questa tesi si compone di tre capitoli. Nel primo capitolo, si presenta una rassegna della letteratura sui principali contributi teorici di modellazione per la progettazione della sicurezza sociale, assumendo gli individui come non-standard preferences. Ci concentriamo su tre approcci particolari: time inconsistent preferences, temptation preferences e myopia. Il secondo capitolo studia gli incentivi politici per la progettazione della politica di sicurezza sociale nelle democrazie competitive con le famiglie lungimiranti e miopi in un ambiente di probabilistic voting. In particolare, l'analisi si concentra sul trade-off tra le dimensioni e il grado di redistribuzione del sistema pensionistico. Il terzo capitolo introduce il comportamento miope di risparmio in un modello pensionistico a due paesi, in cui vengono confrontate le politiche pensionistiche non-cooperative e cooperative. Inoltre, questo capitolo analizza gli effetti di cooperazione per l'accumulo di capitale mondiale con la presenza di agenti miopi.
This dissertation consists of three chapters. In Chapter 1, I present a literature review on the main theoretical contributions modeling social security design assuming non-standard household preferences. We focus on three particular approaches: time inconsistent preferences, temptation preferences and myopia. Chapter 2 investigates the political incentives for the design of social security policy in competitive democracies with both far-sighted and myopic households in a probabilistic voting setting. In particular, the analysis focuses on the trade-off between the size and the redistribution degree of the equilibrium social security policy. Chapter 3 introduces myopic saving behavior in a two-country normative model of social security, in which non-cooperative and cooperative pension policies are compared. Moreover, this chapter analyzes the effects of cooperation to world capital accumulation with the presence of myopic agents.

Questa tesi si compone di tre capitoli. Nel primo capitolo, si presenta una rassegna della letteratura sui principali contributi teorici di modellazione per la progettazione della sicurezza sociale, assumendo gli individui come non-standard preferences. Ci concentriamo su tre approcci particolari: time inconsistent preferences, temptation preferences e myopia. Il secondo capitolo studia gli incentivi politici per la progettazione della politica di sicurezza sociale nelle democrazie competitive con le famiglie lungimiranti e miopi in un ambiente di probabilistic voting. In particolare, l'analisi si concentra sul trade-off tra le dimensioni e il grado di redistribuzione del sistema pensionistico. Il terzo capitolo introduce il comportamento miope di risparmio in un modello pensionistico a due paesi, in cui vengono confrontate le politiche pensionistiche non-cooperative e cooperative. Inoltre, questo capitolo analizza gli effetti di cooperazione per l'accumulo di capitale mondiale con la presenza di agenti miopi.
This dissertation consists of three chapters. In Chapter 1, I present a literature review on the main theoretical contributions modeling social security design assuming non-standard household preferences. We focus on three particular approaches: time inconsistent preferences, temptation preferences and myopia. Chapter 2 investigates the political incentives for the design of social security policy in competitive democracies with both far-sighted and myopic households in a probabilistic voting setting. In particular, the analysis focuses on the trade-off between the size and the redistribution degree of the equilibrium social security policy. Chapter 3 introduces myopic saving behavior in a two-country normative model of social security, in which non-cooperative and cooperative pension policies are compared. Moreover, this chapter analyzes the effects of cooperation to world capital accumulation with the presence of myopic agents.

Despite substantial effort made by the usable security community at facilitating the use of recommended security systems and behaviors, much security advice is ignored and many security systems are underutilized. I argue that this disconnect can partially be explained by the fact that security behaviors have myriad unaccounted for social consequences. For example, by using two-factor authentication, one might be perceived as “paranoid”. By encrypting an e-mail correspondence, one might be perceived as having something to hide. Yet, to date, little theoretical work in usable security has applied theory from social psychology to understand how these social consequences affect people’s security behaviors. Likewise, little systems work in usable security has taken social factors into consideration. To bridge these gaps in literature and practice, I begin to build a theory of social cybersecurity and apply those theoretical insights to create systems that encourage better cybersecurity behaviors. First, through a series of interviews, surveys and a large-scale analysis of how security tools diffuse through the social networks of 1.5 million Facebook users, I empirically model how social influences affect the adoption of security behaviors and systems. In so doing, I provide some of the first direct evidence that security behaviors are strongly driven by social influence, and that the design of a security system strongly influences its potential for social spread. Specifically, security systems that are more observable, inclusive, and stewarded are positively affected by social influence, while those that are not are negatively affected by social influence. Based on these empirical results, I put forth two prescriptions: (i) creating socially grounded interface “nudges” that encourage better cybersecurity behaviors, and (ii) designing new, more socially intelligent end-user facing security systems. As an example of a social “nudge”, I designed a notification that informs Facebook users that their friends use optional security systems to protect their own accounts. In an experimental evaluation with 50,000 Facebook users, I found that this social notification was significantly more effective than a non-social control notification at attracting clicks to improve account security and in motivating the adoption of promoted, optional security tools. As an example of a socially intelligent cybersecurity system, I designed Thumprint: an inclusive authentication system that authenticates and identifies individual group members of a small, local group through a single, shared secret knock. Through my evaluations, I found that Thumprint is resilient to casual but motivated adversaries and that it can reliably differentiate multiple group members who share the same secret knock. Taken together, these systems point towards a future of socially intelligent cybersecurity that encourages better security behaviors. I conclude with a set of descriptive and prescriptive takeaways, as well as a set of open problems for future work. Concretely, this thesis provides the following contributions: (i) an initial theory of social cybersecurity, developed from both observational and experimental work, that explains how social influences affect security behaviors; (ii) a set of design recommendations for creating socially intelligent security systems that encourage better cybersecurity behaviors; (iii) the design, implementation and comprehensive evaluation of two such systems that leverage these design recommendations; and (iv) a reflection on how the insights uncovered in this work can be utilized alongside broader design considerations in HCI, security and design to create an infrastructure of useful, usable and socially intelligent cybersecurity systems.