Nonparametric Instrumental Variables Estimation of a Quantile Regression Model

We consider nonparametric estimation of a regression function that is identified by requiring a specified quantile of the regression “error” conditional on an instrumental variable to be zero. The resulting estimating equation is a nonlinear integral equation of the first kind, which generates an ill‐posed inverse problem. The integral operator and distribution of the instrumental variable are unknown and must be estimated nonparametrically. We show that the estimator is mean‐square consistent, derive its rate of convergence in probability, and give conditions under which this rate is optimal in a minimax sense. The results of Monte Carlo experiments show that the estimator behaves well in finite samples.     

Development and Psychometric Evaluation of a 10-Item Short Form Inventory of Gambling Situations

The Inventory of Gambling Situations (IGS-63; Turner and Littman-Sharp, Inventory of gambling situations users guide, 2006) is a 63-item measure of high-risk gambling situations. It assesses gambling across 10 situational subscales that load onto two higher-order factors: negative and positive situations (Stewart et al. Psychology of Addictive Behaviors, 22:257–268, 2008). While the IGS-63 has excellent psychometric properties (Littman-Sharp et al., The Inventory of Gambling Situations: Reliability, factor structure, and validity (IGS Technical Manual), in press) its length may preclude its use in time-limited contexts. The purpose of this study was to develop and validate a 10-item short-form of the IGS (IGS-10). Each IGS-10 item reflects one of the ten subscale categories from the IGS-63, with two items from the original subscales included as examples for each IGS-10 item. The IGS-10 was administered to 180 undergraduate gamblers along with the IGS-63 and the Problem Gambling Severity Index (PGSI; Ferris and Wynne, Canadian Problem Gambling Index: Final report, 2001). IGS-10 items showed convergent validity with the corresponding IGS-63 subscales (r’s = .60–.73). Principal components analysis of the IGS-10 revealed two factors: negative (α = .84) and positive (α = .85). PGSI scores correlated significantly with all IGS-10 items (r’s = .33–.58) and with both IGS-10 higher-order subscales (r’s = .66 [negative] and .49 [positive]), supporting the criterion validity of the IGS-10. Since minimal information is lost when using the IGS-10, the short form may prove particularly useful when respondent burden prevents using the full IGS-63.     

Pathways to social value and social change: An integrative review of the social entrepreneurship literature

Social entrepreneurship has emerged as an important means of addressing grand challenges. Although research on the topic has accelerated, scholars have yet to articulate an overarching framework that links the different pathways taken by social entrepreneurs with the positive effects of these efforts. To address this shortcoming, we conducted a systematic literature review which enabled us to conceptually differentiate between social value and social change as distinct outcomes of social entrepreneurship and identify seven pathways for achieving these outcomes. Building on our analysis, we outline a research agenda for questions pertaining to: the dynamics between social value and social change; how contextual factors and social entrepreneurs influence various pathways; design principles of business models and innovations that facilitate social value and social change; and defining, measuring, and ensuring accountability for social value and social change.     

Contract Length as Risk Management When Labor is not Homogeneous

This paper examines the choice of contract length for workers who possess unique skills. Uncertainty, facing both the worker and the firm, creates an incentive to reallocate risk. The uncertainty arises from two sources: variation in the market value of the worker's human capital and fluctuation in the worker's physical production. Long‐term contracts are typically modeled as compensating wage differentials, or as a solution to the problem of asymmetric information. This paper develops a model proposing more complex behavior in the reallocation of risk between the contracting parties. The model shows that long‐term labor contracts are most likely to be observed when price uncertainty in the labor market exceeds the worker's productive uncertainty.     

Semiparametric estimation of employment duration models

There are a variety of economic areas, such as studies of employment duration and of the durability of capital goods, in which data on important variables typically are censored. The standard techinques for estimating a model from censored data require the distributions of unobservable random components of the model to be specified a priori up to a finite set of parameters, and misspecification of these distributions usually leads to inconsistent parameter estimates. However, economic theory rarely gives guidance about distributions and the standard estimation techniques do not provide convenient methods for identifying distributions from censored data. Recently, several distribution-free or semiparametric methods for estimating censored regression models have been developed. This paper presents the results of using two such methods to estimate a model of employment duration. The paper reports the operating characteristics of the semiparametric estimators and compares the semiparametric estimates with those obtained from a standard parametric model.     

Quality of earnings: A key factor in financial planning

This paper presents the results of an empirical study based on the premise that, among companies with the same nominal earnings, those with higher quality of earnings will be more highly valued by investors. The price-earnings ratio should be higher for companies with better quality of earnings and lower for companies with poorer quality of earnings. The test is performed by estimating regression equations relating the price-earnings ratio to quality of earnings factors. The study should prove to be of significant value to financial decision-makers in formulating their long range plans.     

The effects of labor market segmentation on economic resources in retirement

Longitudinal data from the Panel Study of Income Dynamics are used to explore the determinants of economic resource levels among recently retired workers. Three income determination models are used to examine significant predictors of economic status using a broad measure of economic well being that includes both retirement income and wealth. Findings indicate that variables used in status attainment, human capital, and labor market segmentation models explain substantial amounts of variance. Applying these models to the longitudinal data provide suggestive information about the crucial life-span characteristics and circumstances that determine economic status as workers enter retirement.     

The Durham Family Initiative: a preventive system of care

This article describes the Durham Family Initiative (DFI), an innovative effort to bring together child welfare and juvenile justice systems to reach DFI's goal of reducing the child abuse rate in Durham, North Carolina, by 50% within the next 10 years. DFI will follow principles of a preventive system of care (PSoC), which focuses on nurturing the healthy parent-child relationship. A community collaborative of government agency directors has signed a memorandum of agreement to implement the PSoC principles. The researchers will use multiple methods to evaluate DFI's efficacy.     

The Doubles: a case study on developing a technology-based substance abuse education curriculum

The Doubles, funded by the National Institute on Drug Abuse, is a seven-episode series of media tools designed to teach third and fourth grade students about the science of drug addiction. The program's curriculum is delivered via a set of videos, interactive CD-ROMs, workbooks, or an Internet site. This article examines the process used to develop The Doubles and argues that its success stems from the careful balancing of the needs of the funding agency, state and national curricular guidelines, and the target audience.