Journal articles: 'Confidence intervals for local weights'

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Chen, Peng, and Nicholas Zabaras. "Adaptive Locally Weighted Projection Regression Method for Uncertainty Quantification." Communications in Computational Physics 14, no. 4 (October 2013): 851–78. http://dx.doi.org/10.4208/cicp.060712.281212a.

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AbstractWe develop an efficient, adaptive locally weighted projection regression (ALWPR) framework for uncertainty quantification (UQ) of systems governed by ordinary and partial differential equations. The algorithm adaptively selects the new input points with the largest predictive variance and decides when and where to add new local models. It effectively learns the local features and accurately quantifies the uncertainty in the prediction of the statistics. The developed methodology provides predictions and confidence intervals at any query input and can deal with multi-output cases. Numerical examples are presented to show the accuracy and efficiency of the ALWPR framework including problems with non-smooth local features such as discontinuities in the stochastic space.

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Proulx, Gilbert. "Body Weights of Adult and Juvenile Northern Pocket Gophers, Thomomys talpoides, in Central Alberta Alfalfa Fields." Canadian Field-Naturalist 119, no. 4 (October 1, 2005): 551. http://dx.doi.org/10.22621/cfn.v119i4.187.

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In an effort to recognize adults from juveniles in late summer and early fall, carcasses of Northern Pocket Gophers (Thomomys talpoides) captured from April to October 1994 in a pure alfalfa (Medicago spp.) field in Camrose and a mixed alfalfa-orchard grass (Dactylis glomerata)-dandelion (Taraxacum spp.) field in Lacombe, in central Alberta were analyzed. Mean weights of adult males and females were significantly (P < 0.05) larger than those of juveniles with near-adult body sizes in late summer and early fall. On the basis of the limits of 95% confidence intervals for individual values in Camrose and Lacombe, live-captured males weighing < 130 g could be classified as juveniles; those that are > 180 g would be adults. Males weighing between 130 and 180 g could be either juveniles or adults. Live-captured females weighing < 110 g would likely be juveniles. With larger animals, the pubic symphysis should be used to distinguish young females from adults. Given the variability of body weight in Northern Pocket Gophers, it is suggested that criteria for aging based on weight be derived for local populations in specific habitat types. On average, Northern Pocket Gopher males and females from Camrose were significantly (P < 0.05) heavier than those of Lacombe. Animals from both fields were, on average, heavier than those previously studied in natural-vegetation communities. Differences in the food nutritional quality may explain the observed variation in body weights among populations.

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Dieli, Onochie Jude, Mika Kato, Gbolahan Solomon Osho, and Oluwagbemiga Ojumu. "The Effects of Wireless Mobile Phone Technology on Economic Growth in Nigeria." Journal of Economics and Behavioral Studies 12, no. 1(J) (April 9, 2020): 7–21. http://dx.doi.org/10.22610/jebs.v12i1(j).2969.

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The market in the telecom industry is often segmented into three categories namely long distance, local and wireless services. In their survey, Green and Teece (1998) used this approach to study the telecom market segmentations of the United Kingdom, Australia, United States and New Zealand. In line with its policy of openness, transparency, fairness and participatory regulation, the commission informed stakeholders in September 2012 of its intent to conduct a study on the level of competition in the relevant markets of Nigeria’s Telecommunications Industry. It held meetings with a cross section of industry operators. This study shows that as the availability of mobile phone technology increases, the volume of import increases and more technology is transferred. Thus, the findings by Freund and Weinhold (2002, 2004) and Arrow (1969) are reconfirmed by the study’s empirical result. Therefore, technology helps to reduce distributional inequality of economic benefits. In fact, this does not necessarily imply reduction in inequality among rich and poor classes of these societies in the respective rich and poor states. The finding suggests that the availability of mobile phone technology increases state economic growth by different marginal weights. However, these marginal weights statistical significance across the states in both 90% and 95% confidence intervals could not be ascertained because the covariance has to be estimated using bootstrap. It is therefore left for future research.

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Ribeiro, Robespierre C., Joel A. Lamounier, Reynaldo G. Oliveira, Isabela M. Bensenor, and Paulo A. Lotufo. "Measurements of adipocity and high blood pressure among children and adolescents living in Belo Horizonte." Cardiology in the Young 19, no. 5 (July 9, 2009): 436–40. http://dx.doi.org/10.1017/s1047951109990606.

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AbstractObjectiveTo verify an association, if it exists, between obesity and blood pressure raised beyond the 90th percentile in children and adolescents, and to determine the measure of adiposity that best correlates with blood pressure in these subjects.DesignCross-sectional study.SettingA school-based study in Belo Horizonte, Brazil.ParticipantsWe selected randomly 1,403 students, aged from 6 to 18 years, from 545,046 students attending 521 public and private schools. Those selected completed the study.Main measures of outcomeWe recorded the weight, height, skin fold in the triceps, subscapular, and suprailiac areas, waist and hip circumference, body-mass index, and resting systolic and diastolic blood pressures using a mercury sphygmomanometer.ResultsIn univariate analyses, body mass index greater or lesser than 85th percentile, measurements of skin thickness in the subscapular and suprailiac areas, and the sum of all measurements of skinfold thickness, were associated with both systolic and diastolic measurements of blood pressure. After multivariate analyses that adjusted for all measurements of adiposity except itself, and age, race, and socioeconomic state, we found that the increased body mass index was associated with a 3.6-fold increased frequency of elevated systolic measurements of blood pressure, with 95% confidence intervals from 2.2 to 5.8, and a 2.7-fold increased frequency of elevated measurements of diastolic blood pressure, with 95% confidence intervals from 1.9 to 4.0.ConclusionsBody-mass index serves as a better predictor of elevated blood pressure among children than do local measurements of adiposity.

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Sreedhara, Meera, Karin Valentine Goins, Christine Frisard, Milagros C. Rosal, and Stephenie C. Lemon. "Stepping Up Active Transportation in Community Health Improvement Plans: Findings From a National Probability Survey of Local Health Departments." Journal of Physical Activity and Health 16, no. 9 (September 1, 2019): 772–79. http://dx.doi.org/10.1123/jpah.2018-0623.

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Background: Local health departments (LHDs) are increasingly involved in Community Health Improvement Plans (CHIPs), a collaborative planning process that represents an opportunity for prioritizing physical activity. We determined the proportion of LHDs reporting active transportation strategies in CHIPs and associations between LHD characteristics and such strategies. Methods: A national probability survey of US LHDs (<500,000 residents; 30.2% response rate) was conducted in 2017 (n = 162). LHDs reported the inclusion of 8 active transportation strategies in a CHIP. We calculated the proportion of LHDs reporting each strategy. Multivariate logistic regression models determined the associations between LHD characteristics and inclusion of strategies in a CHIP. Inverse probability weights were applied for each stratum. Results: 45.6% of US LHDs reported participating in a CHIP with ≥1 active transportation strategy. Proportions for specific strategies ranged from 22.3% (Safe Routes to School) to 4.1% (Transit-Oriented Development). Achieving national accreditation (odds ratio [OR] = 3.67; 95% confidence interval [CI], 1.11–12.05), pursuing accreditation (OR = 3.40; 95% CI, 1.25–9.22), using credible resources (OR = 5.25; 95% CI, 1.77–15.56), and collaborating on a Community Health Assessment (OR = 4.48; 95% CI, 1.23–16.29) were associated with including a strategy in a CHIP after adjusting for covariates. Conclusions: CHIPs are untapped tools, but national accreditation, using credible resources, and Community Health Assessment collaboration may support strategic planning efforts to improve physical activity.

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Ong, Ken K., Pauline Emmett, Kate Northstone, Jean Golding, Imogen Rogers, Andrew R. Ness, Jonathan C. Wells, and David B. Dunger. "Infancy Weight Gain Predicts Childhood Body Fat and Age at Menarche in Girls." Journal of Clinical Endocrinology & Metabolism 94, no. 5 (May 1, 2009): 1527–32. http://dx.doi.org/10.1210/jc.2008-2489.

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Abstract Context: Rapid postnatal weight gain has been associated with subsequent increased childhood adiposity. However, the contribution of rapid weight gain during specific infancy periods is not clear. Objective: We aimed to determine which periods of infancy weight gain are related to childhood adiposity and also to age at menarche in UK girls. Design, Setting, and Participants: A total of 2715 girls from a prospective UK birth cohort study participated in the study. Main Outcome Measures: Routinely measured weights and lengths at ages 2, 9, and 19 months were extracted from the local child health computer database. Body composition was assessed by dual-energy x-ray absorptiometry at age 10 yr, and age at menarche was assessed by questionnaire (categorized into three groups: <12.0, 12.0–13.0, and >13.0 yr). Results: Faster early infancy weight gain between 0 and 2 months and also 2 to 9 months were associated with increased body fat mass relative to lean mass at age 10 yr and also with earlier age at menarche. Each +1 unit gain in weight sd score between 0 and 9 months was associated with an odds ratio (95% confidence interval) = 1.48 (1.27–1.60) for overweight (body mass index > 85th centile) at 10 yr, and 1.34 (1.21–1.49) for menarche at less than 12 yr. In contrast, subsequent weight gain between 9 and 19 months was not associated with later adiposity or age at menarche. Conclusions: In developed settings, rapid weight gain during the first 9 months of life is a risk factor for both increased childhood adiposity and early menarche in girls.

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Gray, Aaron M., and William L. Buford. "Incidence of Patients With Knee Strain and Sprain Occurring at Sports or Recreation Venues and Presenting to United States Emergency Departments." Journal of Athletic Training 50, no. 11 (November 1, 2015): 1190–98. http://dx.doi.org/10.4085/1062-6050-50.11.06.

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Context Knee injuries account for a substantial percentage of all athletic injuries. The relative rates of knee injury for a variety of sports by sex and age need to be understood so we can better allocate resources, such as athletic trainers, to properly assess and treat injuries and reduce injury risk. Objective To describe the epidemiology of patients with sport-related knee strain and sprain presenting to US emergency departments from 2002 to 2011. Design Cross-sectional study. Setting Using the Consumer Products Safety Commission's National Electronic Injury Surveillance System and the US Census Bureau, we extracted raw data to estimate national rates of patients with knee strain and sprain presenting to emergency departments. Patients or Other Participants Participants were individuals sustaining a knee strain or sprain at sports or recreation venues and presenting to local emergency departments for treatment. We included 12 popular sports for males and 11 for females. Ages were categorized in six 5-year increments for ages 5 to 34 years and one 10-year increment for ages 35 to 44 years. Main Outcome Measure(s) Incidence rates were calculated using weights provided by the National Electronic Injury Surveillance System and reported with their 95% confidence intervals for sport, sex, and age. Results Strain and sprain injury rates varied greatly by sport, sex, and age group. The highest injury rates occurred in football and basketball for males and in soccer and basketball for females. The most at-risk population was 15 to 19 years for both sexes. Conclusions Athletes experience different rates of knee strain and sprain according to sport, sex, and age. Increased employment of athletic trainers to care for the highest-risk populations, aged 10 to 19 years, is recommended to reduce emergency department use and implement injury-prevention practices.

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Lobosco, Angelo, and Dan DiBartolomeo. "Approximating the Confidence Intervals for Sharpe Style Weights." Financial Analysts Journal 53, no. 4 (July 1997): 80–85. http://dx.doi.org/10.2469/faj.v53.n4.2103.

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Kim, T. H. "Asymptotic and Bayesian Confidence Intervals for Sharpe-Style Weights." Journal of Financial Econometrics 3, no. 3 (July 1, 2005): 315–43. http://dx.doi.org/10.1093/jjfinec/nbi015.

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Ahankari, Anand, Sharda Bapat, Puja Myles, Andrew Fogarty, and Laila Tata. "Factors associated with preterm delivery and low birth weight: a study from rural Maharashtra, India." F1000Research 6 (January 24, 2017): 72. http://dx.doi.org/10.12688/f1000research.10659.1.

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Background: Although preterm delivery and low birth weight (LBW) have been studied in India, findings may not be generalisable to rural areas such as the Marathwada region of Maharashtra state. There is limited information available on maternal and child health indicators from this region. We aimed to present some local estimates of preterm delivery and LBW in the Osmanabad district of Marathwada and assess available maternal risk factors. Methods: The study used routinely collected data on all in-hospital births in the maternity department of Halo Medical Foundation’s hospital from 1st January 2008 to 31st December 2014. Multivariable logistic regression analysis provided odds ratios (OR) with 95% confidence intervals (CI) for preterm delivery and LBW according to each maternal risk factor. Results: We analysed 655 live births, of which 6.1% were preterm deliveries. Of the full term births (N=615), 13.8% were LBW (<2.5 kilograms at birth). The odds of preterm delivery were three times higher (OR=3.23, 95% CI 1.36 to 7.65) and the odds of LBW were double (OR=2.03, 95% CI 1.14 to 3.60) among women <22 years of age compared with older women. The odds of both preterm delivery and LBW were reduced in multigravida compared with primigravida women regardless of age. Anaemia (Hb<11g/dl), which was prevalent in 91% of women tested, was not significantly related to these birth outcomes. Conclusions: The odds of preterm delivery and LBW were much higher in mothers under 22 years of age in this rural Indian population. Future studies should explore other related risk factors and the reasons for poor birth outcomes in younger mothers in this population, to inform the design of appropriate public health policies that address this issue.

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Wichaidit, Wit, Sawitri Assanangkornchai, and Virasakdi Chongsuvivatwong. "Disparities in behavioral health and experience of violence between cisgender and transgender Thai adolescents." PLOS ONE 16, no. 5 (May 28, 2021): e0252520. http://dx.doi.org/10.1371/journal.pone.0252520.

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Background The term "transgender" refers to an individual whose gender identity is different from their sex assigned at birth, whereas the term "cisgender" refers to an individual whose gender identity is the same as their sex assigned at birth. In Thailand, studies on health outcomes and quality of life of Thai transgender youths have not included assessments from nationally-representative samples. The objective of this study is to assess the extent that behavioral health outcomes and exposure to violence varied by gender among respondents of the National School Survey on Alcohol Consumption, Substance Use and Other Health-Risk Behaviors. Methods We used data from a nationally-representative self-administered survey of secondary school students in years 7, 9 and 11 and classified participants as cisgender boys, cisgender girls, transgender boys, and transgender girls. Participants also answered questions on depressive experience, suicidality, sexual behaviors, alcohol and tobacco use, drug use, and past-year experience of violence. We analyzed data using descriptive statistics and modified multivariate Poisson regression with adjustment for sampling weights to calculate adjusted prevalence ratios (APR) with 95% confidence intervals. Results A total of 31,898 respondents (82.8% of those who returned complete and valid questionnaires) answered questions on sex and gender identity and were included in the analyses (n = 31,898 respondents), approximately 2.5% of whom identified as transgender. Transgender boys had a higher prevalence suicidal ideation than cisgender boys (APR = 2.97; 95% CI = 1.89, 4.67) and cisgender girls (APR = 2.29; 95% CI = 1.55, 3.40). Transgender girls were less likely than cisgender boys and girls to be ever drinkers, while transgender boys were more likely than cisgender boys and girls to be ever drinkers. Transgender girls had higher past-year exposure to sexual violence than cisgender boys (APR = 2.74; 95% CI = 1.52, 4.95) and cisgender girls (APR = 4.93; 95% CI = 2.52, 9.67). Conclusion We found disparities in behavioral health and experience of violence between transgender and cisgender adolescents in Thailand. The findings highlighted the need for program managers and policy makers to consider expanding local efforts to address health gaps in the LGBTQ community to also include school-going youth population.

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Larsen, Robert A., Madeline Bauer, Ann M. Thomas, and J. Richard Graybill. "Amphotericin B and Fluconazole, a Potent Combination Therapy for Cryptococcal Meningitis." Antimicrobial Agents and Chemotherapy 48, no. 3 (March 2004): 985–91. http://dx.doi.org/10.1128/aac.48.3.985-991.2004.

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ABSTRACT We evaluated the antifungal activities of amphotericin B, fluconazole, and flucytosine, alone and in combination, in a murine model of cryptococcal meningitis. The objectives were to determine the greatest antifungal effects achievable with these drugs alone or in combination. Meningitis was established in male BALB/c mice weighing 23 to 25 g by intracerebral injection of Cryptococcus neoformans. Treatment was started on day 2. Amphotericin B was tested at 0.3 to 1.3 mg/kg of body weight/day by slow intravenous injection. Fluconazole at 10 to 40 mg/kg/day and flucytosine at 20 to 105 mg/kg/day were administered in the sole source of drinking water. The mice were killed at 16 days, and the numbers of fungal colonies in the brain were quantified. The association between the response and the dose combination was evaluated by local nonparametric response surface methods; 99% confidence intervals were used to evaluate the antifungal effects. Ninety-five percent of the mice treated with amphotericin B at 0.5 mg/kg survived to the end of the experiment, regardless of the fluconazole or flucytosine dose used. The greatest activity was seen with amphotericin B plus fluconazole with or without flucytosine. However, the addition of flucytosine did not increase the antifungal activity. Given the widespread availability of amphotericin B and fluconazole and the relative safety profile of fluconazole compared to that of flucytosine, the full potential of this two-drug combination deserves further evaluation.

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CHEN, SONG XI, and YONG SONG QIN. "Confidence Intervals Based on Local Linear Smoother." Scandinavian Journal of Statistics 29, no. 1 (March 2002): 89–99. http://dx.doi.org/10.1111/1467-9469.00273.

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Radman, Ivan, Maroje Sorić, and Marjeta Mišigoj-Duraković. "Prevalence of Key Modifiable Cardiovascular Risk Factors among Urban Adolescents: The CRO-PALS Study." International Journal of Environmental Research and Public Health 17, no. 9 (May 2, 2020): 3162. http://dx.doi.org/10.3390/ijerph17093162.

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The occurrence of chronic diseases in youth has become a serious global issue requiring early prevention. Due to the specific environment in large cities, urban youth are especially exposed to risky lifestyle patterns. Objective: This survey aimed to determine the prevalence of key modifiable cardiovascular risk factors in the adolescent population of the Croatian capital Zagreb. Methods: A clustered two-stage random sample design was employed to select a representative group of 903 adolescents (girls n = 444; boys n = 459; age 15.6 ± 0.4) starting their secondary education. Participants were invited to fulfil an electronic questionnaire meant to collect data on daily physical activity, screen time and tobacco use. In addition, anthropometric and blood pressure measurements were taken by medically trained personnel. Data that were not originally categorical were dichotomized based on internationally accepted cut-off values for each risk factor, summarized for females and males, and presented as percentages and 95% confidence intervals. Results: The outcomes suggest that that more than one half did not meet the recommended daily physical activity (girls 59.4%; boys 45.5%), while about one quarter exceeded 2 h of screen time per day and had high blood pressure (girls 26.6% and 21.6%; boys 27.0% and 27.0%, respectively). Moreover, the results indicated nearly one fifth of adolescents had excess weight (girls 16.1%; boys 22.2%) and a similar proportion smoked tobacco (girls 20.8%; boys 17.0%). Conclusions: Local and regional health stakeholders should make additional efforts to promote healthy lifestyles in urban teenagers. Special emphasis should be placed on promoting physical activity.

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Swenson, Tami. "Deprescribing and Polypharmacy for Medicare Beneficiaries Under Guardianship in Long-Term Care Facilities." Innovation in Aging 4, Supplement_1 (December 1, 2020): 83–84. http://dx.doi.org/10.1093/geroni/igaa057.274.

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Abstract Local judicial courts vary in the amount of supervision they provide guardians, which makes the practice of guardianship uneven. To begin to address the evidence gap to inform best practices for persons under guardianship care, this study examines the issues of polypharmacy and prescribing patterns for four therapeutic classes most commonly targeted for deprescribing for older adults. The Medicare Current Beneficiary Survey (MCBS) for 2015 and 2016 is used to examine facility-dwelling Medicare beneficiaries under guardianship compared with those that are not. Logistic regression is used to examine association of polypharmacy outcomes and guardianship care controlling for patient and facility characteristics. Statistical models are adjusted using Fay’s Method with replicate weights for the MCBS complex survey design. Approximately 12% of the facility-dwelling Medicare population in 2015 and 2016 are persons under guardianship care. Persons under guardianship were more likely to have polypharmacy or to be prescribed 5 or more medications (Odd Ratio (OR)=1.168, 95% Confidence Interval (CI)=1.156 to 1.180, p<0.001) than facility-dwelling Medicare beneficiaries not under guardianship care. Medicare beneficiaries under guardianship were more likely to be prescribed PPIs (OR=1.229, 95% CI=1.222 to 1.237, p<0.001) or antipsychotic medications (OR=1.240, 95% CI=1.232 to 1.247, p<0.001) but less likely to be prescribed benzodiazepines (OR=0.920, 95% CI=0.913 to 0.927, p<0.001) or antihyperglycemics (OR-0.726, 95% CI=0.721 to 0.731, p<0.001). Medical decision support services, such as guardianship care, are increasing in importance as shared decision making between patients and physicians evolves to address polypharmacy and deprescribing for older adults.

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Henrion, R., G. Henrion, K. Szukalski, I. Fabian, A. Thiesies, and P. Heininger. "Parametric and bootstrap estimations of confidence intervals for representative sample weights." Fresenius' Journal of Analytical Chemistry 340, no. 1 (1991): 1–5. http://dx.doi.org/10.1007/bf00324381.

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Chen, S. X. "Empirical likelihood confidence intervals for local linear smoothers." Biometrika 87, no. 4 (December 1, 2000): 946–53. http://dx.doi.org/10.1093/biomet/87.4.946.

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Tercan, A. E., and P. A. Dowd. "Approximate local confidence intervals under change of support." Mathematical Geology 27, no. 1 (January 1995): 149–72. http://dx.doi.org/10.1007/bf02083572.

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Marshall, Charles R. "Confidence intervals on stratigraphic ranges." Paleobiology 16, no. 1 (1990): 1–10. http://dx.doi.org/10.1017/s0094837300009672.

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Observed stratigraphic ranges almost always underestimate true longevities. Strauss and Sadler (1987, 1989) provide a method for calculating confidence intervals on the endpoints of local stratigraphic ranges. Their method can also be applied to composite sections; confidence intervals may be placed on times of origin and extinction for entire species or lineages. Confidence interval sizes depend only on the length of the stratigraphic range and the number of fossil horizons. The technique's most important assumptions are that fossil horizons are distributed randomly and that collecting intensity has been uniform over the stratigraphic range. These assumptions are more difficult to test and less likely to be fulfilled for composite sections than for local sections.Confidence intervals give useful baseline estimates of the incompleteness of the fossil record, even if the underlying assumptions cannot be tested. Confidence intervals, which can be very large, should be calculated when the fossil record is used to assess absolute rates of molecular or morphological evolution, especially for poorly preserved groups. Confidence intervals have other functions: to determine how rich the fossil record has to be before radiometric dating errors become the dominant source of error in estimated times of origin or extinction; to predict future fossil finds; to predict which species with fossil records should be extant; and to assess phylogenetic hypotheses and taxonomic assignments.

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Nyandiko, Winstone Mokaya, Paul Kiptoon, and Florence Ajaya Lubuya. "Neonatal hypothermia and adherence to World Health Organisation thermal care guidelines among newborns at Moi Teaching and Referral Hospital, Kenya." PLOS ONE 16, no. 3 (March 23, 2021): e0248838. http://dx.doi.org/10.1371/journal.pone.0248838.

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Neonatal hypothermia is a great concern with near epidemic levels globally. In Kenya, its prevalence is as high as 87% with limited local data on the associated factors such as adherence to warm chain guidelines as recommended by the World Health Organisation (WHO) is limited. This study aimed to determine the prevalence of hypothermia and level of adherence to the WHO thermal care guidelines among newborns admitted at Moi Teaching and Referral Hospital (MTRH). It adopted a prospective study design of following up neonates for the first 24 hours of admission to the MTRH newborn unit. Thermometry, interview of mothers and observation of thermal care practices was done. Descriptive and inferential statistical techniques were adopted. Specifically, Pearson’s chi-square test of associations between predictors of neonatal hypothermia and management outcomes was conducted with their corresponding risk estimates at 95% confidence interval. Among the 372 participants, 64.5% (n = 240) were born at MTRH, 47.6% (177) were preterm and 53.2% (198) had birth weights below 2500 grams. Admission hypothermia was noted among 73.7% (274) and 13% (49) died on the first day of admission. Only 7.8% (29) newborns accessed optimal thermal care. Prematurity, day one mortality and adherence to the warm chain were significantly (p<0.001) associated with admission hypothermia. Inappropriate thermal appliance, inadequate clothing and late breastfeeding significantly increased the risk of neonatal hypothermia. Absence of admission hypothermia increased the likelihood of neonatal survival more than twenty-fold (AOR = 20.91, 95% CI: 2.15–153.62). Three out four neonates enrolled had admission hypothermia which was significantly associated with prematurity, lack of adherence to warm chain and increased risk of neonatal mortality on the first day of life. There was low adherence to the WHO thermal care guidelines. This should be optimized among preterm neonates to improve likelihood of survival.

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Brannath, W., and S. Schmidt. "Informative Simultaneous Confidence Intervals in Hierarchical Testing." Methods of Information in Medicine 53, no. 04 (2014): 278–83. http://dx.doi.org/10.3414/me13-01-0140.

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SummaryBackground and Objectives: In clinical trials involving multiple tests it is often difficult to obtain informative simultaneous confidence intervals (SCIs). In particular in hierarchical testing, no quantification of effects is possible for the first tested (and most important) hypothesis after its rejection. Our goal is a construction of SCIs that are always informative.Methods: We present an approach where the level is split after rejection of each hypothesis to obtain an informative confidence bound. The splitting weights are continuous functions of the parameters. Our method is realizable by a simple algorithm and is illustrated by an intuitive graphical representation.Results: We show theoretically and by an example that the new SCIs always provide information when a hypothesis is rejected. The power to reject the first hypothesis is not smaller than for the classical fixed-sequence procedure. The price for the extra information is a small power loss in the hypotheses proceeding the most important one.Conclusions: Given the substantial gain in information, a small loss of power for the non-primary hypotheses seems often acceptable. Especially in the context of non-inferiority trials, this method is a useful alternative. The flexibility in the choice of the weight functions makes the procedure attractive for applications.

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Antonieta, Juliana Souza de Almeida Aranha Camargo, Sergio de Almeida Basano, and Luís Marcelo Aranha Camargo. "Prevalence of chronic noncommunicable diseases and their associated factors in adults over 39 years in riverside population in the Western Brazilian Amazon region." Journal of Human Growth and Development 32, no. 1 (January 31, 2022): 55–63. http://dx.doi.org/10.36311/jhgd.v32.11323.

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The prevalence of Chronic Noncommunicable Disease (CND) are rocketting over the world, including in young adults. The WHO estimates that more than half of the deaths in the world are caused by CND. A cross-sectional study was carried out from june to november 2016. The researchers visited 16 communities, with a sample size of 183 adult individuals performed for convenience. The patients went through screening and verified: weight, height, abdominal circumference, blood pressure, clinical-epidemiological history and performed physical and laboratory examination. Prevalence ratios were calculated with confidence intervals of 95% and with statistical significance with p<0.05. This study aims to estimate the prevalence of CND and its associated factors in the elderly riverside population of the Rio Madeira in Humaitá, Amazonas State, Western Brazilian Amazon. The prevalence of systemic arterial hypertension (SAH) was 44.7%, 52.6% in female. Of the individuals with SAH, 77.5% did not use medication. About 51.5% of them had Grade I SAH. The prevalence of type 2 diabetes mellitus was 16.4%, where no patient used medication and about 40.4% of the studied population fits in the glucose intolerance range. Metabolic syndrome presented a prevalence of 24.0%, with a higher frequency in females (33.8%) (p=0.007). Concerning chronic kidney disease, a prevalence of 12.1% was observed in both genders. The associated factors found were alcoholism, smoking, sedentary lifestyle and obesity, and more than 45% of the patients had at least two associated factors. The population had a high prevalence of CND and associated factors, low frequency of medication use, revealing inefficiency of the local health system. Increased coverage of the Governmental Family Health Strategy (GFHS) and the increase in number of trained Community Health Assistants , together with health education actions can increase the population’s health standard.

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Mangin, B., B. Goffinet, and A. Rebaï. "Constructing confidence intervals for QTL location." Genetics 138, no. 4 (December 1, 1994): 1301–8. http://dx.doi.org/10.1093/genetics/138.4.1301.

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Abstract We describe a method for constructing the confidence interval of the QTL location parameter. This method is developed in the local asymptotic framework, leading to a linear model at each position of the putative QTL. The idea is to construct a likelihood ratio test, using statistics whose asymptotic distribution does not depend on the nuisance parameters and in particular on the effect of the QTL. We show theoretical properties of the confidence interval built with this test, and compare it with the classical confidence interval using simulations. We show in particular, that our confidence interval has the correct probability of containing the true map location of the QTL, for almost all QTLs, whereas the classical confidence interval can be very biased for QTLs having small effect.

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FETZ, THOMAS. "MULTIVARIATE MODELS AND VARIABILITY INTERVALS: A LOCAL RANDOM SET APPROACH." International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems 19, no. 05 (October 2011): 799–823. http://dx.doi.org/10.1142/s0218488511007246.

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This article is devoted to the propagation of families of variability intervals through multivariate functions comprising the semantics of confidence limits. At fixed confidence level, local random sets are defined whose aggregation admits the calculation of upper probabilities of events. In the multivariate case, a number of ways of combination is highlighted to encompass independence and unknown interaction using random set independence and Fréchet bounds. For all cases we derive formulas for the corresponding upper probabilities and elaborate how they relate. An example from structural mechanics is used to exemplify the method.

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Simon, Michael S., Theresa Hastert, Juhua Luo, Rowan T. Chlebowski, Julie J. Ruterbusch, and Jennifer Lynn Beebe-Dimmer. "Cardiometabolic risk factors and survival after cancer in the women’s health initiative." Journal of Clinical Oncology 37, no. 15_suppl (May 20, 2019): 1556. http://dx.doi.org/10.1200/jco.2019.37.15_suppl.1556.

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1556 Background: Features associated with metabolic syndrome have been connected to both risk and poorer outcomes for certain cancers. Methods: We used data on 12,107 women enrolled in the Women’s Health Initiative diagnosed prospectively with either local or regional stage cancer to evaluate the association between cardiometabolic risk factors identified at study entry, (elevated waist circumference (WC), hypertension, high cholesterol, and presence of type 2 diabetes), with death from either cancer, cardiovascular disease (CVD), or other causes. Cancer sites included those previously linked in the published literature to metabolic syndrome and cancer risk: breast, colorectal, endometrial, non-Hodgkin’s lymphoma, kidney, pancreatic, ovarian, stomach and liver. Multiple imputation methods were used to account for missing data (6.9%). Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI), adjusted for other significant predictors of survival. Results: After a median follow-up of 10.0 years, there were 3,612 total deaths with 1,547 (43 %) due to cancer. Most participants (60.3%) had at least 2 cardiometabolic risk factors, and 5.8% had 3 or 4. Having 3-4 risk factors, was associated with significantly higher mortality due to cancer (HR: 1.39, 95% CI: 1.12, 1.71), CVD (HR: 2.62, 95% CI: 1.91, 3.59), and other causes (HR: 1.97, 95% CI: 1.57-2.47) compared with no risk factors. High WC was associated with higher mortality due to cancer and other causes, and history of diabetes, and hypertension were associated with higher mortality due to CVD, and other causes. Conclusions: Among women diagnosed with early or regional stage cancer, the presence of 3-4 cardiometabolic risk factors which is consistent with a diagnosis of metabolic syndrome, are significantly associated with death due to cancer, CVD, and other causes. Attention to primary prevention focused on weight control, physical activity and diet after cancer diagnosis and treatment, can have an important positive influence on survivorship after cancer.

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Croux, Cristophe, and Catherine Dehon. "Estimators of the multiple correlation coefficient: Local robustness and confidence intervals." Statistical Papers 44, no. 3 (July 2003): 315–34. http://dx.doi.org/10.1007/s00362-003-0158-7.

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Amadou, Z., and B. H. Mohammed. "Marketing Expansion Strategies for Local Crops-Based Couscous in Tahoua State, Niger Republic." Nigerian Journal of Basic and Applied Sciences 28, no. 2 (April 26, 2021): 70–80. http://dx.doi.org/10.4314/njbas.v28i2.9.

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This study investigates the own-price and cross-price elasticities for locally grown crops-based couscous and compares confidence intervals computation for willingness-to-pay and market shares under Krinsky Robb and Delta bootstrapping methods. Syntheses of previous literature and a focus group with consumers had helped to identify nine brands of couscous included in this research. The fractional factorial design was used to collect data from three hundred consumers, while the multinomial logit was used to analyze data. Results indicate that rice, cowpea and millet-based couscous were the most preferred by consumers and their market share accounts of more than fifty percent. The Results from simulation showed that confidence intervals under Krinsky and Robb stabilize as a sample size increases and thereby adjusting for skewness. However, confidence intervals under Delta computation are constant regardless of sample size, thereby failing to adjust for skewness. Finally, results also indicate that skewness was also accommodated in confidence intervals for market share because its values progressively adjust as sample size increases. These findings may be useful to boost cropbased couscous demand in the study area and beyond and thereby improving farmers’ revenue and offering diet diversification opportunity. Keywords: Marketing expansion, Strategies, Local crops, Couscous, Willingness-to-pay

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Zhang, Xinyu, and Chu-An Liu. "INFERENCE AFTER MODEL AVERAGING IN LINEAR REGRESSION MODELS." Econometric Theory 35, no. 4 (September 4, 2018): 816–41. http://dx.doi.org/10.1017/s0266466618000269.

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This article considers the problem of inference for nested least squares averaging estimators. We study the asymptotic behavior of the Mallows model averaging estimator (MMA; Hansen, 2007) and the jackknife model averaging estimator (JMA; Hansen and Racine, 2012) under the standard asymptotics with fixed parameters setup. We find that both MMA and JMA estimators asymptotically assign zero weight to the under-fitted models, and MMA and JMA weights of just-fitted and over-fitted models are asymptotically random. Building on the asymptotic behavior of model weights, we derive the asymptotic distributions of MMA and JMA estimators and propose a simulation-based confidence interval for the least squares averaging estimator. Monte Carlo simulations show that the coverage probabilities of proposed confidence intervals achieve the nominal level.

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De Brabanter, K., Y. Liu, and C. Hua. "Convergence rates for uniform confidence intervals based on local polynomial regression estimators." Journal of Nonparametric Statistics 28, no. 1 (November 26, 2015): 31–48. http://dx.doi.org/10.1080/10485252.2015.1113283.

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Divine, D. V., J. Polzehl, and F. Godtliebsen. "A propagation-separation approach to estimate the autocorrelation in a time-series." Nonlinear Processes in Geophysics 15, no. 4 (July 23, 2008): 591–99. http://dx.doi.org/10.5194/npg-15-591-2008.

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Abstract. The paper presents an approach to estimate parameters of a local stationary AR(1) time series model by maximization of a local likelihood function. The method is based on a propagation-separation procedure that leads to data dependent weights defining the local model. Using free propagation of weights under homogeneity, the method is capable of separating the time series into intervals of approximate local stationarity. Parameters in different regions will be significantly different. Therefore the method also serves as a test for a stationary AR(1) model. The performance of the method is illustrated by applications to both synthetic data and real time-series of reconstructed NAO and ENSO indices and GRIP stable isotopes.

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Armstrong, Timothy B., and Michal Kolesár. "Simple and honest confidence intervals in nonparametric regression." Quantitative Economics 11, no. 1 (2020): 1–39. http://dx.doi.org/10.3982/qe1199.

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We consider the problem of constructing honest confidence intervals (CIs) for a scalar parameter of interest, such as the regression discontinuity parameter, in nonparametric regression based on kernel or local polynomial estimators. To ensure that our CIs are honest, we use critical values that take into account the possible bias of the estimator upon which the CIs are based. We show that this approach leads to CIs that are more efficient than conventional CIs that achieve coverage by undersmoothing or subtracting an estimate of the bias. We give sharp efficiency bounds of using different kernels, and derive the optimal bandwidth for constructing honest CIs. We show that using the bandwidth that minimizes the maximum mean‐squared error results in CIs that are nearly efficient and that in this case, the critical value depends only on the rate of convergence. For the common case in which the rate of convergence is n −2/5, the appropriate critical value for 95% CIs is 2.18, rather than the usual 1.96 critical value. We illustrate our results in a Monte Carlo analysis and an empirical application.

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Stark, H., and R. Amirfeyz. "Cochrane corner: local corticosteroid injection for carpal tunnel syndrome." Journal of Hand Surgery (European Volume) 38, no. 8 (September 24, 2013): 911–14. http://dx.doi.org/10.1177/1753193413490848.

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Background: Carpal tunnel syndrome is a clinical syndrome manifested by signs and symptoms of irritation of the median nerve at the carpal tunnel in the wrist. Local corticosteroid injection for carpal tunnel syndrome has been studied but its effectiveness is unknown. Objectives: To evaluate the effectiveness of local corticosteroid injection for carpal tunnel syndrome versus placebo injection or other non-surgical interventions. Search methods: We searched the Cochrane Neuromuscular Disease Group Trials register (searched May 2006), MEDLINE (searched January 1966 to May 2006), EMBASE (searched January 1980 to May 2006) and CINAHL (searched January 1982 to May 2006). Selection criteria: Randomized or quasi-randomized studies. Data collection and analysis: Three authors independently selected the trials and rated their overall quality. Relative risks and 95% confidence intervals were calculated for each trial and summary relative risks and 95% confidence intervals were also calculated.

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Preuß, M., and A. Ziegler. "A Simplification and Implementation of Random-effects Meta-analyses Based on the Exact Distribution of Cochran’s Q." Methods of Information in Medicine 53, no. 01 (2014): 54–61. http://dx.doi.org/10.3414/me13-01-0073.

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SummaryBackground: The random-effects (RE) model is the standard choice for meta-analysis in the presence of heterogeneity, and the stand ard RE method is the DerSimonian and Laird (DSL) approach, where the degree of heterogeneity is estimated using a moment-estimator. The DSL approach does not take into account the variability of the estimated heterogeneity variance in the estimation of Cochran’s Q. Biggerstaff and Jackson derived the exact cumulative distribution function (CDF) of Q to account for the variability of Ť 2.Objectives: The first objective is to show that the explicit numerical computation of the density function of Cochran’s Q is not required. The second objective is to develop an R package with the possibility to easily calculate the classical RE method and the new exact RE method.Methods: The novel approach was validated in extensive simulation studies. The different approaches used in the simulation studies, including the exact weights RE meta-analysis, the I 2 and T 2 estimates together with their confidence intervals were implemented in the R package metaxa.Results: The comparison with the classical DSL method showed that the exact weights RE meta-analysis kept the nominal type I error level better and that it had greater power in case of many small studies and a single large study. The Hedges RE approach had inflated type I error levels. Another advantage of the exact weights RE meta-analysis is that an exact confidence interval for T 2is readily available. The exact weights RE approach had greater power in case of few studies, while the restricted maximum likelihood (REML) approach was superior in case of a large number of studies. Differences between the exact weights RE meta-analysis and the DSL approach were observed in the re-analysis of real data sets. Application of the exact weights RE meta-analysis, REML, and the DSL approach to real data sets showed that conclusions between these methods differed.Conclusions: The simplification does not require the calculation of the density of Cochran’s Q, but only the calculation of the cumulative distribution function, while the previous approach required the computation of both the density and the cumulative distribution function. It thus reduces computation time, improves numerical stability, and reduces the approximation error in meta-analysis. The different approaches, including the exact weights RE meta-analysis, the I 2 and T 2estimates together with their confidence intervals are available in the R package metaxa, which can be used in applications.

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Surette, Tobie, and Jacques Allard. "A regression mixture with logistic weights for modeling heterogeneous crustacean growth data when the maturity phase is unknown." Canadian Journal of Fisheries and Aquatic Sciences 65, no. 5 (May 1, 2008): 1003–11. http://dx.doi.org/10.1139/f08-023.

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Piecewise linear models (PLMs) have been used widely in crustacean morphometry and growth modeling when subjects belong to more than one undetermined maturity stage, for example, to model immature and adolescent male snow crab (Chionoecetes opilio) growth increment at moulting as a function of pre-moult size. PLMs assume, unrealistically, that the transition between the maturity stages occurs at a fixed size. PLMs have also often been applied without taking into account the heterogeneity of variance or without supplying parameter confidence intervals. We propose to describe the unknown maturity stage and the known growth increments as functions of the pre-moult size by regression mixture with logistic weights (RMLW), where a logistic function and two linear regressions are mixed with weights provided by the logistic function. Errors are assumed to be normally distributed with a standard deviation depending linearly on the expected growth increment. Parameters and their confidence intervals are obtained using maximum likelihood. Model diagnostic procedures and a posteriori maturity stage classification methods are presented. The methodology is applied to 1311 snow crab growth observations, and results are compared with those of other snow crab studies. The methodology has widespread applications to crustacean morphometry and can be generalized to nonlinear relationships.

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Clifford, David, and Yi Guo. "Combining two soil property rasters using an adaptive gating approach." Soil Research 53, no. 8 (2015): 907. http://dx.doi.org/10.1071/sr14275.

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Given the wide variety of ways one can measure and record soil properties, it is not uncommon to have multiple overlapping predictive maps for a particular soil property. One is then faced with the challenge of choosing the best prediction at a particular point, either by selecting one of the maps, or by combining them together in some optimal manner. This question was recently examined in detail when Malone et al. (2014) compared four different methods for combining a digital soil mapping product with a disaggregation product based on legacy data. These authors also examined the issue of how to compute confidence intervals for the resulting map based on confidence intervals associated with the original input products. In this paper, we propose a new method to combine models called adaptive gating, which is inspired by the use of gating functions in mixture of experts, a machine learning approach to forming hierarchical classifiers. We compare it here with two standard approaches – inverse-variance weights and a regression based approach. One of the benefits of the adaptive gating approach is that it allows weights to vary based on covariate information or across geographic space. As such, this presents a method that explicitly takes full advantage of the spatial nature of the maps we are trying to blend. We also suggest a conservative method for combining confidence intervals. We show that the root mean-squared error of predictions from the adaptive gating approach is similar to that of other standard approaches under cross-validation. However under independent validation the adaptive gating approach works better than the alternatives and as such it warrants further study in other areas of application and further development to reduce its computational complexity.

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Alemdjrodo, Kangni, and Yichuan Zhao. "Novel empirical likelihood inference for the mean difference with right-censored data." Statistical Methods in Medical Research 31, no. 1 (October 8, 2021): 87–104. http://dx.doi.org/10.1177/09622802211041767.

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This paper focuses on comparing two means and finding a confidence interval for the difference of two means with right-censored data using the empirical likelihood method combined with the independent and identically distributed random functions representation. In the literature, some early researchers proposed empirical link-based confidence intervals for the mean difference based on right-censored data using the synthetic data approach. However, their empirical log-likelihood ratio statistic has a scaled chi-squared distribution. To avoid the estimation of the scale parameter in constructing confidence intervals, we propose an empirical likelihood method based on the independent and identically distributed representation of Kaplan–Meier weights involved in the empirical likelihood ratio. We obtain the standard chi-squared distribution. We also apply the adjusted empirical likelihood to improve coverage accuracy for small samples. In addition, we investigate a new empirical likelihood method, the mean empirical likelihood, within the framework of our study. The performances of all the empirical likelihood methods are compared via extensive simulations. The proposed empirical likelihood-based confidence interval has better coverage accuracy than those from existing methods. Finally, our findings are illustrated with a real data set.

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Lajaunie, C. "Comparing some approximate methods for building local confidence intervals for predicting regionalized variables." Mathematical Geology 22, no. 1 (January 1990): 123–44. http://dx.doi.org/10.1007/bf00890301.

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Strauss, David, and Peter M. Sadler. "Classical confidence intervals and Bayesian probability estimates for ends of local taxon ranges." Mathematical Geology 21, no. 4 (May 1989): 411–27. http://dx.doi.org/10.1007/bf00897326.

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BAHARUMSHAH, Ahmad Zubaidi, Siew-Voon SOON, Stilianos FOUNTAS, and Nurul Sima MOHAMAD SHARIFF. "PERSISTENCE OF REAL EXCHANGE RATES IN THE CENTRAL AND EASTERN EUROPEAN COUNTRIES." Journal of Business Economics and Management 17, no. 3 (June 7, 2016): 381–96. http://dx.doi.org/10.3846/16111699.2015.1101396.

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We investigate the mean reversion in real exchange rates for Central and Eastern European countries. We use point and confidence interval estimates from the Phillips et al.’s (2001) local-persistent model as our preferred measures of the persistence of real exchange rates. We find that the adjustment to purchasing power parity is more rapid after accounting for structural breaks, with half-life deviation from parity below 18 months, which is consistent with the explanation based on nominal rigidities. The estimated narrow confidence intervals for the half-lives invalidate the purchasing power parity puzzle for transition and some core European Union countries. The novelty of our results lies in the finding of strong evidence for purchasing power parity as the local-persistent model produces shorter half-lives and much narrower corresponding confidence intervals than those obtained by standard Dickey-Fuller and local-to-unity models. Our evidence for PPP suggests that the transition countries have maintained their long-run competitiveness against their trading partners.

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Lee, Younghyun, David K. Han, and Hanseok Ko. "Reinforced AdaBoost Learning for Object Detection with Local Pattern Representations." Scientific World Journal 2013 (2013): 1–14. http://dx.doi.org/10.1155/2013/153465.

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A reinforced AdaBoost learning algorithm is proposed for object detection with local pattern representations. In implementing Adaboost learning, the proposed algorithm employs an exponential criterion as a cost function and Newton’s method for its optimization. In particular, we introduce an optimal selection of weak classifiers minimizing the cost function and derive the reinforced predictions based on a judicial confidence estimate to determine the classification results. The weak classifier of the proposed method produces real-valued predictions while that of the conventional Adaboost method produces integer valued predictions of +1 or −1. Hence, in the conventional learning algorithms, the entire sample weights are updated by the same rate. On the contrary, the proposed learning algorithm allows the sample weights to be updated individually depending on the confidence level of each weak classifier prediction, thereby reducing the number of weak classifier iterations for convergence. Experimental classification performance on human face and license plate images confirm that the proposed method requires smaller number of weak classifiers than the conventional learning algorithm, resulting in higher learning and faster classification rates. An object detector implemented based on the proposed learning algorithm yields better performance in field tests in terms of higher detection rate with lower false positives than that of the conventional learning algorithm.

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Xu, Stanley, Colleen Ross, Marsha A. Raebel, Susan Shetterly, Christopher Blanchette, and David Smith. "Use of Stabilized Inverse Propensity Scores as Weights to Directly Estimate Relative Risk and Its Confidence Intervals." Value in Health 13, no. 2 (March 2010): 273–77. http://dx.doi.org/10.1111/j.1524-4733.2009.00671.x.

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García-Fiñana, Marta, Simon S. Keller, and Neil Roberts. "Confidence intervals for the volume of brain structures in Cavalieri sampling with local errors." Journal of Neuroscience Methods 179, no. 1 (April 2009): 71–77. http://dx.doi.org/10.1016/j.jneumeth.2009.01.026.

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Ganics, Gergely, Atsushi Inoue, and Barbara Rossi. "Confidence Intervals for Bias and Size Distortion in IV and Local Projections-IV Models." Journal of Business & Economic Statistics 39, no. 1 (October 11, 2019): 307–24. http://dx.doi.org/10.1080/07350015.2019.1660175.

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Yuan, Shi man, and Fan xiu Li. "Recognition criteria and application of lake eutrophication evaluation based on set pair analysis." International Journal of Scientific Research and Management 8, no. 08 (August 18, 2020): 405–13. http://dx.doi.org/10.18535/ijsrm/v8i08.ec01.

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The set pair analysis evaluation method has been applied to evaluate water quality. However, in real-life applications, because traditional assessing methods usually yield extreme results and are of poor resolution, a hybrid recognition criterion, entropy weight and set pair analysis model is established. The concepts and calculated methods of assessment grade fuzzy characteristic and confidence criterion were proposed in order to solve the problem of determination of the magnitude of lake eutrophication. And the weight value was calculated by entropy weight method and finally got the evaluation grade as a confidence interval based on confidence level. Compared with the set pair analysis based on triangular fuzzy number method (SPA(TFN)) and the improved set pair analysis method (ISPA), the evaluating results of this model are more reasonable and its resolving power is higher. This study offer new insights and possibility to carry out an efficient way for lake eutrophication status evaluation. The study also provides scientific reference in lake risk management for local and national governmental agencies.

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Xu, S., C. Ross, MA Raebel, S. Shetterly, CM Blanchette, and DH Smith. "PMC47 USE OF STABILIZED INVERSE PROPENSITY SCORES AS WEIGHTS TO DIRECTLY ESTIMATE RELATIVE RISK AND ITS CONFIDENCE INTERVALS." Value in Health 12, no. 3 (May 2009): A28. http://dx.doi.org/10.1016/s1098-3015(10)73198-3.

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Liao, Zhipeng, and Xiaoxia Shi. "A nondegenerate Vuong test and post selection confidence intervals for semi/nonparametric models." Quantitative Economics 11, no. 3 (2020): 983–1017. http://dx.doi.org/10.3982/qe1312.

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This paper proposes a new model selection test for the statistical comparison of semi/non‐parametric models based on a general quasi‐likelihood ratio criterion. An important feature of the new test is its uniformly exact asymptotic size in the overlapping nonnested case, as well as in the easier nested and strictly nonnested cases. The uniform size control is achieved without using pretesting, sample‐splitting, or simulated critical values. We also show that the test has nontrivial power against all n ‐local alternatives and against some local alternatives that converge to the null faster than n . Finally, we provide a framework for conducting uniformly valid post model selection inference for model parameters. The finite sample performance of the nondegenerate test and that of the post model selection inference procedure are illustrated in a mean‐regression example by Monte Carlo.

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Xu, Yuanyuan, and Genke Yang. "A Short-Term Wind Speed Forecasting Hybrid Model Based on Empirical Mode Decomposition and Multiple Kernel Learning." Complexity 2020 (November 2, 2020): 1–13. http://dx.doi.org/10.1155/2020/8811407.

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Short-term wind speed forecasting plays an increasingly important role in the security, scheduling, and optimization of power systems. As wind speed signals are usually nonlinear and nonstationary, how to accurately forecast future states is a challenge for existing methods. In this paper, for highly complex wind speed signals, we propose a multiple kernel learning- (MKL-) based method to adaptively assign the weights of multiple prediction functions, which extends conventional wind speed forecasting methods using a support vector machine. First, empirical mode decomposition (EMD) is used to decompose complex signals into several intrinsic mode function component signals with different time scales. Then, for each channel, one multiple kernel model is constructed for forecasting the current sequence signal. Finally, several experiments are carried out on different New Zealand wind farm data, and the relevant prediction accuracy indexes and confidence intervals are evaluated. Extensive experimental results show that, compared with existing machine learning methods, the EMD-MKL model proposed in this paper has better performance in terms of the prediction accuracy evaluation indexes and confidence intervals and shows a better ability to generalize.

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Rosnow, Ralph L., and Robert Rosenthal. "Effect Sizes." Zeitschrift für Psychologie / Journal of Psychology 217, no. 1 (January 2009): 6–14. http://dx.doi.org/10.1027/0044-3409.217.1.6.

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The effect size (ES) is the magnitude of a study outcome or research finding, such as the strength of the relationship obtained between an independent variable and a dependent variable. Two types of ES indicators are sampled here: the difference-type and the correlational (or r-type). Both are well suited to situations in which there are two groups or two conditions, whereas the r-type, used in association with focused statistical procedures (contrasts), is also ideal in situations where there are more than two groups or conditions and there are predicted overall patterns to be evaluated. Also discussed are procedures for computing confidence intervals and null-counternull intervals as well as a systematic approach to comparing and combining competing predictions expressed in the form of contrast weights and ES indicators.

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Marshall, Charles R. "Using Confidence Intervals to Quantify the Uncertainty in the End-Points of Stratigraphic Ranges." Paleontological Society Papers 16 (October 2010): 291–316. http://dx.doi.org/10.1017/s1089332600001911.

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One of the many contributions paleontology makes to our understanding of the biosphere and its evolution is a direct temporal record of biotic events. However, assuming fossils have been correctly identified and accurately dated, stratigraphic ranges underestimate true temporal ranges: observed first occurrences are too young, and observed last occurrences are too old. Here I introduce the techniques developed for placing confidence intervals on the end-points of stratigraphic ranges. I begin with the analysis of single taxa in local sections – with the simplest of assumptions – random fossilization. This is followed by a discussion of the methods developed to handle the fact that the recovery of fossils is often non-random in space and time. After discussion of how confidence intervals can be used to test for simultaneous origination and extinctions, I conclude with an example application of confidence intervals to unravel the relative importance of background extinction, environmental change and mass extinction of ammonite species at the end of the Cretaceous in western Tethys.

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Rahman, Raziur, Saad Haider, Souparno Ghosh, and Ranadip Pal. "Design of Probabilistic Random Forests with Applications to Anticancer Drug Sensitivity Prediction." Cancer Informatics 14s5 (January 2015): CIN.S30794. http://dx.doi.org/10.4137/cin.s30794.

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Random forests consisting of an ensemble of regression trees with equal weights are frequently used for design of predictive models. In this article, we consider an extension of the methodology by representing the regression trees in the form of probabilistic trees and analyzing the nature of heteroscedasticity. The probabilistic tree representation allows for analytical computation of confidence intervals (CIs), and the tree weight optimization is expected to provide stricter CIs with comparable performance in mean error. We approached the ensemble of probabilistic trees’ prediction from the perspectives of a mixture distribution and as a weighted sum of correlated random variables. We applied our methodology to the drug sensitivity prediction problem on synthetic and cancer cell line encyclopedia dataset and illustrated that tree weights can be selected to reduce the average length of the CI without increase in mean error.

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Journal articles on the topic 'Confidence intervals for local weights'

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