Academic literature on the topic 'Positive assortative mating'
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Journal articles on the topic "Positive assortative mating"
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Greenwood, Jeremy, Nezih Guner, Georgi Kocharkov, and Cezar Santos. "Marry Your Like: Assortative Mating and Income Inequality." American Economic Review 104, no. 5 (May 1, 2014): 348–53. http://dx.doi.org/10.1257/aer.104.5.348.
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Has there been an increase in positive assortative mating? Does assortative mating contribute to household income inequality? Data from the United States Census Bureau suggests there has been a rise in assortative mating. Additionally, assortative mating affects household income inequality. In particular, if matching in 2005 between husbands and wives had been random, instead of the pattern observed in the data, then the Gini coefficient would have fallen from the observed 0.43 to 0.34, so that income inequality would be smaller. Thus, assortative mating is important for income inequality. The high level of married female labor-force participation in 2005 is important for this result.
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Ólafsdóttir, Gudbjörg Á., Michael G. Ritchie, and Sigurdur S. Snorrason. "Positive assortative mating between recently described sympatric morphs of Icelandic sticklebacks." Biology Letters 2, no. 2 (March 6, 2006): 250–52. http://dx.doi.org/10.1098/rsbl.2006.0456.
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Recently, models of sympatric speciation have suggested that assortative mating can develop between sympatric morphs due to divergence in an ecologically important character. For example, in sympatric pairs of threespine stickleback ( Gasterosteus aculeatus L.) size-assortative mating seems to be instrumental in reproductive isolation. Here, we examine courtship behaviour and assortative mating of newly described sympatric stickleback morphs in Lake Thingvallavatn, Iceland. We find that the two morphs show strong positive assortative mating. However, the mechanism involved in mate choice does not seem to be as straightforward as in other similar systems of sympatric stickleback morphs and may involve variation in nest type.
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Clark, H. L., and P. R. Y. Backwell. "Assortative mating in a fiddler crab." Behaviour 153, no. 2 (2016): 175–85. http://dx.doi.org/10.1163/1568539x-00003333.
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Non-random mating, particularly positive size-assortative mating, is common and can have major evolutionary consequences. The causes of size-assortative mating, however, are rarely examined. Here we explore the possibility of sexual selection, mate availability and mating constraints causing the strong correlation between male and female sizes in the fiddler crabUca mjoebergi. We show that the full size range of males is available to females throughout the mating period, so mate availability is unlikely to cause size-assortative mating in this species. We also show that mechanical constraints do not prevent females from entering the burrows or mating with the full size range of males. We suggest that the strong size assortative mating that we observed throughout the mating cycle is driven by sexual selection. Both males and females prefer large partners. The benefit to mating with large partners needs further investigation.
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Delestrade, Anne. "Sexual Size Dimorphism and Positive Assortative Mating in Alpine Choughs (Pyrrhocorax graculus)." Auk 118, no. 2 (April 1, 2001): 553–56. http://dx.doi.org/10.1093/auk/118.2.553.
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Abstract The degree of sexual size dimorphism in a number of different morphological characters was examined in a social corvid, the Alpine Chough, using measurements taken on 178 males and 144 females. A small amount of size dimorphism appeared in all morphological characters, and weight was the most dimorphic character. To identify if Alpine Choughs mate assortatively, measurements of mates were compared in 76 pairs. A positive assortative mating was found on tarsus length, and a small positive trend is suggested between body condition of partners, but that needs to be confirmed with a larger sample size.
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Fox, S., C. N. Johnson, R. Brooks, and M. J. Lewis. "Polymorphism, mate choice and sexual selection in the Gouldian finch (Erythrura gouldiae)." Australian Journal of Zoology 50, no. 2 (2002): 125. http://dx.doi.org/10.1071/zo02002.
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Mate choice can result in both assortative mating and directional sexual selection, but few studies have addressed both processes simultaneously. Here we test several hypotheses regarding the possible role of female mate choice in maintaining the face-colour polymorphism of, and affecting directional sexual selection in, the Gouldian finch. These endangered Australian finches are highly sexually dimorphic and are genetically polymorphic for face colour: there are black-, red- and gold-faced individuals. First we showed that Gouldian finches tend to pair positive-assortatively by face colour morph in aviaries. In a laboratory experiment, we tested whether female mate choice is assortative by face colour. Overall, females neither preferred males of the same or of different face colour morphs as themselves. We found weak evidence for positive assortative female choice at one of the two loci involved in determining face colour. Next, we tested whether females showed frequency-dependent mate choice, and found that they preferred neither rare nor common male morphs. In order to test for directional sexual selection on males by female mate choice, we examined the correlations between male morphological traits and attractiveness to females. We found that tail pin length and bill size are correlated with male attractiveness, and may be under sexual selection. Thus, whilst female mate choice may be an important process in determining the evolution of male morphology, and potentially sexual dimorphism, it does not appear to be the primary force behind the assortative mating pattern among the face colour morphs.
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Class, Barbara, and Jon E. Brommer. "Shared environmental effects bias phenotypic estimates of assortative mating in a wild bird." Biology Letters 14, no. 7 (July 2018): 20180106. http://dx.doi.org/10.1098/rsbl.2018.0106.
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Assortative mating is pervasive in wild populations and commonly described as a positive correlation between the phenotypes of males and females across mated pairs. This correlation is often assumed to reflect non-random mate choice based on phenotypic similarity. However, phenotypic resemblance between mates can also arise when their traits respond plastically to a shared environmental effect creating a (within-pair) residual correlation in traits. Using long-term data collected in pairs of wild blue tits and a covariance partitioning approach, we empirically demonstrate that such residual covariance indeed exists and can generate phenotypic correlations (or mask assortative mating) in behavioural and morphometric traits. These findings (i) imply that residual covariance is likely to be common and bias phenotypic estimates of assortative mating, which can have consequences for evolutionary predictions, (ii) call for the use of rigorous statistical approaches in the study of assortative mating, and (iii) show the applicability of one of these approaches in a common study system.
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González, Fernando Antonio Ignacio, and Juan Antonio Dip. "The Impact of Educational Assortative Mating on Income Inequality: Evidence from Argentina." Journal of Population and Social Studies 30 (November 10, 2021): 116–27. http://dx.doi.org/10.25133/jpssv302022.008.
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This paper seeks to quantify the impact of educational assortative mating on income inequality among households in Argentina. We use microdata from two household surveys conducted by the National Institute of Statistics and Census: The Permanent Household Survey and the National Survey of Risk Factors. We construct contingency tables and perform a regression analysis to study the existence of educational assortative mating. We also present counterfactual simulations of random re-matching of observations. The results show that a sizeable proportion of couples are educationally homogamous (45%). Comparing the Gini coefficients calculated in the real matching and the simulated scenarios, we observe a reduction of up to 4 points. Thus, the educational assortative mating represents a relevant dimension to explain income inequality. Our results recommend considering this matching pattern when defining optimal income taxes; this is, if there is a high positive covariance between the income of both members of the couple, it seems appropriate, from a redistributive point of view, to define income taxes at the household level and not at the individual level (as is currently the case in most countries, including Argentina).
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Kramarenko, S. S., and A. S. Kramarenko. "On Mate Choice in two Xerophilic Species of Land Snails, Brephulopsis cylindrica (Pulmonata, Enidae) and Xeropicta derbentina (Pulmonata, Hygromiidae)." Vestnik Zoologii 53, no. 3 (June 1, 2019): 237–44. http://dx.doi.org/10.2478/vzoo-2019-0023.
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Abstract The cases of assortative mating are known in varied species of Gastropoda, however it is unclear how widely distributed this reproductive strategy is across the class. The data concerning land snails (Stylommatophora) are especially contradictory. By using two model species of stylommatophoran mollusks, Brephulopsis cylindrica (Menke, 1828) and Xeropicta derbentina (Krynicki, 1836), we conducted a long-term observation of their copulatory behavior in Southern Ukraine. In X. derbentina, a clear pattern of the positive assortative mating with respect to body size was found, whereas assortative mating in relation to shell banding polymorphism was revealed in 2 cases out of 7. B. cylindrica snails copulate with any available mate partner, regardless of its size.
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Räsänen, Katja, Matthieu Delcourt, Lauren J. Chapman, and Andrew P. Hendry. "Divergent Selection and Then What Not: The Conundrum of Missing Reproductive Isolation in Misty Lake and Stream Stickleback." International Journal of Ecology 2012 (2012): 1–14. http://dx.doi.org/10.1155/2012/902438.
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In ecological speciation, reproductive isolation evolves as a consequence of adaptation to different selective environments. A frequent contributor to this process is the evolution of positive assortative mate choice between ecotypes. We tested this expectation for lake and inlet stream threespine stickleback (Gasterosteus aculeatus) from the Misty system (Vancouver Island, Canada), which show strong genetically based adaptive divergence and little genetic exchange in nature. This, and work on other stickleback systems, led us to expect positive assortative mating. Yet, our standard “no-choice” laboratory experiment on common-garden fish revealed no evidence for this—despite divergence in traits typically mediating assortative mating in stickleback. These results remind us that divergent natural selection may not inevitably lead to the evolution of positive assortative mate choice. The apparent lack of strong and symmetric reproductive barriers in this system presents a conundrum: why are such barriers not evident despite strong adaptive divergence and low gene flow in nature?
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Yu, Tong Lei, Yao Hui Deng, Juan Zhang, and Li Peng Duan. "Size-assortative copulation in the simultaneously hermaphroditic pond snail Radix auricularia (Gastropoda: Pulmonata)." Animal Biology 66, no. 3-4 (2016): 239–47. http://dx.doi.org/10.1163/15707563-00002501.
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To better understand the importance of body size in hermaphroditic mating, we studied the mating behaviour of the pond snail Radix auricularia. This simultaneous hermaphrodite exhibits a positive correlation between body size and egg production and provides weak evidence for size-assortative mating. In addition to this mating pattern, the partner performing the male role was significantly smaller than the mounted partner, performing the female role. In this study, two laboratory experiments were done to test whether body size has (1) an effect on mate choice of the sperm donor, and (2) poses mechanical constraints. These snails did not display physical limitation in mating with a much larger or smaller partner. In the mate choice experiment, we found no evidence for significant preferences for large partners. Therefore, mate choice of sperm donor and mechanical constraints are not likely to contribute to the formation of size-assortatively mating pairs in this species, which contributes to understanding about how these processes work in hermaphrodites.
Dissertations / Theses on the topic "Positive assortative mating"
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Lstibůrek, Milan. "Population response to positive assortative mating in forest tree breeding." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-03142005-083542/.
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Positive assortative mating (PAM) may substantially enhance genetic variance in a breeding population (BP). This creates potential for additional genetic gains available through production populations (PP) to forest plantations. Open-nucleus strategies (NB) have been incorporated in forest tree breeding programs. In NB, the BP is subdivided into two hierarchical levels, a nucleus and a main population, and can be considered a less rigorous form of PAM. First, PAM was compared to NB by stochastic simulation considering jointly genetic gain and diversity within the framework of a long-term breeding program. Test effort was either assumed constant throughout the entire BP or was redirected according to the rank of each mate. The simulation revealed that PAM results in larger gains in the PP compared to NB under both situations and at any target PP diversity. Second, the test effort during PAM was redirected by varying family sizes as a linear function of mid-parent BLUP values. The actual distribution of mid-parent BLUP values was standardized by a constant value, which was varied in simulation scenarios to cover the entire range of the distribution of family sizes. When equal numbers of progenies were selected per family and the variation in family sizes was maximized, only a minimal reduction in BP diversity was observed, compared to cases with constant family sizes. Under such favorable conditions, the redistribution of resources increased genetic response and variance in the BP, causing substantially greater genetic response in the PP. These conclusions were verified under a mixed-inheritance model with a major-gene locus contributing to variation in a quantitative trait. Finally, the investigation of PAM was extended by considering correlated traits within the framework of a clonal forestry program. The success of somatic embryogenesis in families generated by crossing elite genotypes developed in the breeding program was either considered exponentially distributed or constant. The distribution of success caused non-significant differences in genetic gain of PP. These conclusions were verified over a range of correlation, heritabilities and economic weights of traits.
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Kreikemeier, Udo, and Jens Wrona. "Two-Way Migration between Similiar Countries." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-197867.
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We develop a model to explain two-way migration of high-skilled individuals between countries that are similar in their economic characteristics. High-skilled migration results from the combination of workers whose abilities are private knowledge, and a production technology that gives incentives to firms for hiring workers of similar ability. In the presence of migration cost, high-skilled workers self-select into the group of migrants. The laissez-faire equilibrium features too much migration, explained by a negative migration externality. We also show that for sufficiently low levels of migration cost the optimal level of migration, while smaller than in the laissez-faire equilibrium, is strictly positive. Finally, we extend our model into different directions to capture stylized facts in the data and show that our baseline results also hold in these more complex modelling environments.
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Korzhenevych, Artem, and Johannes Bröcker. "Investment Subsidies and Regional Welfare: A Dynamic Framework." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-235416.
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Subsidising investment in lagging regions is an important regional policy instrument in many countries. Some argue that this instrument is not specific enough to concentrate the aid towards the regions that are lagging behind most, because investment subsidies benefit capital owners who might reside elsewhere, possibly in very rich places. Checking under which conditions this is true is thus highly policy relevant. The present paper studies regional investment subsidies in a multiregional neoclassical dynamic framework. We set up a model with trade in heterogeneous goods, with a perfectly integrated financial capital market and sluggish adjustment of regional capital stocks. Consumers and investors act under perfect foresight. We derive the equilibrium system, show how to solve it, and simulate actual European regional subsidies in computational applications. We find that the size of the welfare gains depends on the portfolio distribution held by the households. If households own diversified asset portfolios, we find that the supported regions gain roughly the amounts that are allocated to them in the form of investment subsidies. If they only own local capital stocks, a part of the money is lost through the drop in share prices. From the point of view of total welfare, the subsidy is not efficient. It can lead to a welfare loss for the EU as a whole and definitely leads to welfare losses in the rest of the world, from where investment ows to the supported EU regions.
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Kreikemeier, Udo, and Jens Wrona. "Two-Way Migration between Similiar Countries." Technische Universität Dresden, 2015. https://tud.qucosa.de/id/qucosa%3A29256.
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We develop a model to explain two-way migration of high-skilled individuals between countries that are similar in their economic characteristics. High-skilled migration results from the combination of workers whose abilities are private knowledge, and a production technology that gives incentives to firms for hiring workers of similar ability. In the presence of migration cost, high-skilled workers self-select into the group of migrants. The laissez-faire equilibrium features too much migration, explained by a negative migration externality. We also show that for sufficiently low levels of migration cost the optimal level of migration, while smaller than in the laissez-faire equilibrium, is strictly positive. Finally, we extend our model into different directions to capture stylized facts in the data and show that our baseline results also hold in these more complex modelling environments.
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Kim, Sunjin. "Essays on Network formation games." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/104598.
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This dissertation focuses on studying various network formation games in Economics. We explore a different model in each chapter to capture various aspects of networks. Chapter 1provides an overview of this dissertation. Chapter 2 studies the possible Nash equilibrium configurations in a model of signed network formation as proposed by Hiller (2017). We specify the Nash equilibria in the case of heterogeneous agents. We find 3 possible Nash equilibrium configurations: Utopia network, positive assortative matching, and disassortative matching. We derive the specific conditions under which they arise in a Nash equilibrium. In Chapter 3, we study a generalized model of signed network formation game where the players can choose not only positive and negative links but also neutral links. We check whether the results of the signed network formation model in the literature still hold in our generalized framework using the notion of pairwise Nash equilibrium. Chapter 4 studies inequality in a weighted network formation model using the notion of Nash equilibrium. As a factor of inequality, there are two types of players: Rich players and poor players. We show that both rich and poor players designate other rich players as their best friends. As a result, We present that nested split graphs are drawn from survey data because researchers tend to ask respondents to list only a few friends.Doctor of Philosophy
This dissertation focuses on studying various network formation games in Economics. We explore a different model in each chapter to capture various aspects of networks. Chapter 1 provides an overview of this dissertation. Chapter 2 studies the possible singed network configurations in equilibrium. In the signed network, players can choose a positive (+) relationship or a negative (-) relationship toward each other player. We study the case that the players are heterogeneous. We find 3 possible categories of networks in equilibrium: Utopia network, positive assortative matching, and disassortative matching. We derive the specific conditions under which they arise in equilibrium. In Chapter 3, we study a generalized model of signed network formation game where the players can choose not only positive and negative links but also neutral links. We check whether the results of the signed network formation model in the literature still hold in our generalized framework. Chapter 4 studies inequality in a weighted network formation model using the notion of Nash equilibrium. In this weighted network model, each player can choose the level of relationship. As a factor of inequality, there are two types of players: rich players and poor players. We show that both rich and poor players choose other rich players as their best friends. As a result, we present that nested split graphs are drawn from survey data because these social network data are censored due to the limit of the number of responses.
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Egger, Hartmut, Peter Egger, Udo Kreickemeier, and Christoph Moser. "The Exporter Wage Premium When Firms and Workers are Heterogeneous." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-227402.
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We set up a trade model with heterogeneous firms and a worker population that is heterogeneous in two dimensions: workers are either skilled or unskilled, and within each skill category there is a continuum of abilities. Workers with high abilities, both skilled and unskilled, are matched to firms with high productivities, and this leads to wage differentials within each skill category across firms. Self-selection of the most productive firms into exporting generates an exporter wage premium, and our framework with skilled and unskilled workers allows us to decompose this premium into its skill-specific components. We employ linked employer-employee data from Germany to structurally estimate the parameters of the model. Using these parameter estimates, we compute an average exporter wage premium of 5 percent. The decomposition by skill turns out to be quantitatively highly relevant, with exporting firms paying no wage premium at all to their unskilled workers, while the premium for skilled workers is 12 percent.
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Milán, Pau. "The Social economics of networks and learning." Doctoral thesis, Universitat Pompeu Fabra, 2016. http://hdl.handle.net/10803/393733.
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This thesis explores various economic environments where the structure of social interactions across individuals determines outcomes. In the first chapter, I study mutual insurance arrangements restricted on a social network. I test the network-based sharing rules on data from Bolivian communities, and I argue that this framework provides a reinterpretation of the standard risk sharing results, predicting household heterogeneity in response to income shocks. In the second paper, I study individual and collective behavior in coordination games where information is dispersed through a network. I show how changes in the distribution of connectivities in the population affect the types of coordination in equilibrium as well as the probability of success. In the third chapter, I explore a framework of learning and turnover in the labor market. I show that positive assortative matching (PAM) extends beyond the stable environment of Eeckhout & Weng (2010) to a situation of residual uncertainty that exhibits periods of unlearning. I also extend this setting to allow for career concerns and I show that PAM can only be sustained under strong assumptions.Esta tesis explora diversos entornos económicos en los que la estructura de las interacciones sociales entre los individuos determina los distintos resultados. En el primer capítulo, se estudia acuerdos de seguro mutuo restringidos en una red social. Utilizo datos de comunidades bolivianas para medir las predicciones teóricas y encuentro que los intercambios observados entre los hogares coinciden con la regla de reparto basada en la red obtenida por la teoría. Sostengo que este marco ofrece una reinterpretación de los resultados estándar de distribución de riesgos, prediciendo heterogeneidad entre los hogares en respuesta a los shocks de ingresos. En el segundo artículo, estudio el comportamiento individual y colectivo en juegos de coordinación, donde la información se dispersa a través de una red. Demuestro cómo los cambios en la distribución de las conectividades de la población afectan a los tipos de coordinación en equilibrio, así como la probabilidad de éxito. En el tercer capítulo, analizo un marco de aprendizaje y cambio de personal en el mercado de trabajo. Muestro que emparejamiento selectivo positivo (PAM) se extiende más allá del entorno estable de Eeckhout y Weng (2010) a una situación de incertidumbre residual que exhibe períodos de des-aprendizaje. También extiendo esta configuración para permitir elementos de career concerns y muestro que el equilibrio de PAM sólo puede sostenerse bajo fuertes supuestos.
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Lstibůrek, Milan. "Population response to positive assortative mating in forest tree breeding." 2005. http://www.lib.ncsu.edu/theses/available/etd-03142005-083542/unrestricted/etd.pdf.
Full textBooks on the topic "Positive assortative mating"
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Walsh, Bruce, and Michael Lynch. Short-term Changes in the Variance: 1. Changes in the Additive Variance. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198830870.003.0016.
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Selection changes the additive-genetic variance (and hence the response in the mean) by both changing allele frequencies and by generating correlations among alleles at different loci (linkage disequilibrium). Such selection-induced correlations can be generated even between unlinked loci, and (generally) are negative, such that alleles increasing trait values tend to become increasingly negative correlated under direction or stabilizing selection, and positively correlated under disruptive selection. Such changes in the additive-genetic variance from disequilibrium is called the Bulmer effects. For a large number of loci, the amount of change can be predicted from the Bulmer equation, the analog of the breeder's equation, but now for the change in the variance. Upon cessation of selection, any disequilibrium decays away, and the variances revert back to their additive-genic variances (the additive variance in the absence of disequilibrium). Assortative mating also generates such disequilibrium.
Book chapters on the topic "Positive assortative mating"
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Basov, Suren, and Ishaq Bhatti. "Shariah Compliance, Positive Assortative Matching and the Performance of IFI’s." In Islamic Finance in the Light of Modern Economic Theory, 145–51. London: Palgrave Macmillan UK, 2016. http://dx.doi.org/10.1057/978-1-137-28662-8_13.
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"Positive Assortative Mating." In Encyclopedia of Personality and Individual Differences, 3965. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-24612-3_302001.
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Galichon, Alfred. "One-Dimensional Case." In Optimal Transport Methods in Economics. Princeton University Press, 2016. http://dx.doi.org/10.23943/princeton/9780691172767.003.0004.
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This chapter considers the Monge–Kantorovich problem in the one-dimensional case, when both the worker and the job are characterized by a scalar attribute. The important assumption of positive assortative matching, or supermodularity of the matching surplus, is introduced and discussed. As a consequence, the primal problem has an explicit solution (an optimal assignment) which is related to the probabilistic notion of a quantile transform, and the dual problem also has an explicit solution (a set of equilibrium prices), which are obtained from the solution to the primal problem. As a consequence, the Monge–Kantorovich problem is explicitly solved in dimension one under the assumption of positive assortative matching.
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Chiappori, Pierre-André. "Matching under Imperfectly Transferable Utility." In Matching with Transfers. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691171739.003.0007.
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This chapter considers matching models under imperfectly transferable utility (ITU). Some of the techniques used in the transferable utility (TU) case can be extended to an ITU framework; for example, the Spence-Mirrlees condition, which is sufficient for positive assortative matching (PAM), can be generalized to the ITU case. Furthermore, individual utilities may be recovered (up to a constant, as in the TU case), using techniques which are essentially similar to their TU counterpart. After providing an overview of the basic notions and theoretical framework of matching under ITU, the chapter discusses the recovery of individual utilities, PAM, and econometrics of ITU. It also presents two examples of applications of ITU techniques, one dealing with matching on wages and the other with endogenous Pareto weights.