A BAYESIAN INTERPRETATION OF MULTIPLE POINT ESTIMATES

Consider a large number of econometric investigations using different estimation techniques and/or different subsets of all available data to estimate a fixed set of parameters. The resulting empirical distribution of point estimates can be shown - under suitable conditions - to coincide with a Bayesian posterior measure on the parameter space induced by a minimum information procedure. This Bayesian interpretation makes it easier to combine the results of various empirical exercises for statistical decision making. The collection of estimators may be generated by one investigator to ensure the satisfaction of our conditions, or they may be collected from published works, where behavioral assumptions need to be made regarding the dependence structure of econometric studies.     

A sequential design for a clinical trial with a linear prognostic factor

We study a randomized adaptive design to assign one of the L$L$ treatments to patients who arrive sequentially by means of an urn model. At each stage n$n$, a reward is distributed between treatments. The treatment applied is rewarded according to its response, 0?_Yn?1$0?Y_n?1$, and 1-_Yn$1-Y_n$ is distributed among the other treatments according to their performance until stage n-1$n-1$. Patients can be classified in K+1$K+1$ levels and we assume that the effect of this level in the response to the treatments is linear. We study the asymptotic behavior of the design when the ordinary least square estimators are used as a measure of performance until stage n-1$n-1$.     

On the simple linear regression model with correlated measurement errors

The simple linear regression model with measurement error has been subject to much research. In this work we will focus on this model when the error in the explanatory variable is correlated with the error in the regression equation. Specifically, we are interested in the comparison between the ordinary errors-in-variables estimator of the regression coefficient β$\beta$ and the estimator that takes account of the correlation between the errors. Based on large sample approximations, we compare the estimators and find that the estimator that takes account of the correlation should be preferred in most situations. We also compare the estimators in small sample situations. This is done by stochastic simulation. The results show that the estimators behave quite similarly in most of the simulated situations, but that the ordinary errors-in-variables estimator performs considerably worse than the estimator that takes account of the correlation for certain parameter combinations. In addition, we look briefly into the bias introduced by ignoring correlated errors when computing sample correlations, and in predictions.     

犍陀罗本生雕刻的印度文化母题

犍陀罗本生雕刻作为印度文化母题的视觉化形式,以叙事性图像生动地阐释印度民间广泛推崇的价值观。犍陀罗本生雕刻的文化母题包括具有普世意义的乐善好施的传统;以轮回报应为理论基础,以孝敬忠贞为核心的伦理道德观念;奉行虔诚于神和克制苦行的修身理念。这些文化母题真实地再现了古代印度人民的社会理想、家庭关系和人生追求,是今人理解古印度文化的可靠资料。     

The Access of the Young Graduates in Sciences into R&D Profession: A Switching Model Treatment for the French Case

We address the question concerning the choice of graduates in sciences and engineering to look for employment in research and development. We use an endogenous switching regression to avoid the existence of self‐selection biases. The study shows that human capital is decisive where both employment opportunities and remuneration are concerned within, but not without, this sector. The results also suggest that in the early stages of a career, the R&D sector is less rewarding than other types of employment only for doctors and not for graduates from engineering schools.     

Employability of Young Italian Men after a Jobless Period, 1989–98

In this paper we investigate the existence of negative jobless duration dependence and the impact of jobless spells on future wages. Our findings are somewhat out of line compared with analogous explorations. We find evidence of very long unemployment duration of the young male labor force, higher than reported anywhere else in Western Europe, as well as large negative unemployment duration dependence. On the other hand, young Italian men experiencing jobless periods in their early careers face small re‐employment wage losses. Such losses do increase with the duration of joblessness, but they are lower than reported in the USA, Canada, the UK, France, and Spain.     

Informal Referrals,Employment, and Wages: Seeking Causal Relationships

Employers and job seekers rely extensively on informal referrals to fill vacancies or to find a job. The widespread use of job contacts has been largely associated with labor outcomes, such as finding a job or even affecting wages. This paper explores whether the use of informal referrals on the job search process affects labor market outcomes of Colombian urban workers. Results indicate that informal referrals are slightly more successful than other job search strategies in term of job seeker's placement. However, referred workers earn in average less than their non‐referred counterparts. Yet, this is only true in formal‐sector positions.     

Firm Size and Employment Dynamics: Estimations of Labor Demand Elasticities Using a Fractional Panel Probit Model

This paper examines the comprehensive discussion on the relationship between job creation, or destruction and firm size. More specifically, the study will determine whether the argument about small‐ and medium‐sized enterprises (SMEs) showing higher employment dynamics is confirmed or not. As such, the following work applies elasticities from a standard labor demand model derived from the estimations of fractional probit models for panel data, as process recommended in Papke and Wooldridge [2008; Journal of Econometrics 145(1–2): 121–133]. Elasticities are a useful measure of employment dynamics, if it is assumed that SMEs act on the same markets. The elasticity results from German establishment data illustrate that firm size does matter for the increase or decrease of employment. SMEs with less than 10 workers exhibit a higher employment dynamic, compared with other entities, at each respective percentile in the distribution of the wage share. Additionally, the outcome of the analysis weakly confirms the hypothesis that smaller firms are more restricted to capital markets, compared with large entities. The results also illustrate that firm size only explains one aspect of job creation and destruction. As stated in the well‐known Hicks–Marshall rules for elasticities of factor demand, the results illustrate that the reaction of labor demand on economic changes increases with the share of labor. Firms with a high share of labor also have larger elasticities, compared with firms with a strong use of capital. Both effects, the size effect and the effect of the proportion of labor, would blend in reality, and therefore, possibly lead to controversial results for the relationship between firm size and employment dynamics. In addition, a model with a negative relationship among both variables is too simple to explain the behavior of firms.     

Vacancy Referrals,Job Search,and the Duration of Unemployment: A Randomized Experiment

One goal of the Public Employment Service is to facilitate matching between unemployed job‐seekers and job vacancies; another goal is to monitor job search so as to bring search efforts among the unemployed in line with search requirements. The referral of job‐seekers to vacancies is one instrument used for these purposes. We report results from a randomized Swedish experiment where the outcome of referrals is examined. To what extent do unemployed individuals actually apply for the jobs they are referred to? Does information to job‐seekers about increased monitoring affect the probability of applying and the probability of leaving unemployment? The experiment indicates that a relatively large fraction (one‐third) of the referrals do not result in job applications. Information about intensified monitoring causes an increase in the probability of job application, especially among young people. However, we find no significant impact on the duration of unemployment.     

Non‐linear Effects of Comparison Income in Quit Decisions: Status versus Signal!

This research note utilizes German matched employer–employee data to investigate the relationship between mobility and relative wage positions within establishments for workers without university degrees. The main innovation involves the examination of non‐linear effects, because previous literature mainly analyses mean linear effects. Our random‐effects probit estimates of mobility suggest a non‐linear U‐shaped effect with respect to relative standing. This is plausible because workers in low relative wage positions might quit because of their low status and those in high relative wage positions because of their low career advancement opportunities. Consideration of non‐linearities, thus, is a major improvement for the analysis of the effects of relative wage positions.