This paper marks Social Security’s open group liability to market taking into account the riskiness of its aggregate benefit payments and tax receipts. The open group liability references the present value of the system’s net cash flow from now through the indefinite future. We treat the growth rates of the system’s aggregate benefits and taxes as implicit securities that are spanned by the ret...

Social Security's special minimum primary insurance amount (PIA) provision was enacted in 1972 to increase the adequacy of benefits for regular long-term, low-earning covered workers and their dependents or survivors. At the time, Social Security also had a regular minimum benefit provision for persons with low lifetime average earnings and their families. Concerns were rising that the low life...

INTRODUCTION The purpose of this study was to determine costs and benefits of visual acuity screening (VAS) or photoscreening (PS) in children. METHODS A societal-perspective, decision-analytic model compared VAS and PS conducted in three age groups: children 6 to 18 months, 3 to 4 years, and 7 to 8 years old. Literature estimates of sensitivity, specificity, and prevalence were used. Cost es...

This paper inverts the usual logic of applied optimal income taxation. It starts from the observed distribution of income before and after redistribution and corresponding marginal tax rates. Under a set of simplifying assumptions, it is then possible to recover the social welfare function that would make the observed marginal tax rate schedule optimal. In this framework, the issue of the optim...

Knowledge sharing behavior in virtual communities has long been an important area of research. Prior related research has primarily focused on relational virtual community (RVC) where knowledge sharing is regarded as a social exchange behavior, heavily depending on the social concerns such as reciprocity, identification and norms. The objective of our study is to investigate knowledge contribut...

BACKGROUND Risk prediction models have been proposed for various diseases and are being improved as new predictors are identified. A major challenge is to determine whether the newly discovered predictors improve risk prediction. Decision curve analysis has been proposed as an alternative to the area under the curve and net reclassification index to evaluate the performance of prediction models...