A new generalized Weibull distribution in income economic inequality curves

Researchers have been developing various extensions and modified forms of the Weibull distribution to enhance its capability for modeling and fitting different data sets. In this note, we investigate the potential usefulness of the new modification to the standard Weibull distribution called odd Weibull distribution in income economic inequality studies. Some mathematical and statistical properties of this model are proposed. We obtain explicit expressions for the first incomplete moment, quantile function, Lorenz and Zenga curves and related inequality indices. In addition to the well-known stochastic order based on Lorenz curve, the stochastic order based on Zenga curve is considered. Since the new generalized Weibull distribution seems to be suitable to model wealth, financial, actuarial and especially income distributions, these findings are fundamental in the understanding of how parameter values are related to inequality. Also, the estimation of parameters by maximum likelihood and moment methods is discussed. Finally, this distribution has been fitted to United States and Austrian income data sets and has been found to fit remarkably well in compare with the other widely used income models.     

The context of employment discrimination: interpreting the findings of a field experiment

Although field experiments have documented the contemporary relevance of discrimination in employment, theories developed to explain the dynamics of differential treatment cannot account for differences across organizational and institutional contexts. In this article, I address this shortcoming by presenting the main empirical findings from a multi‐method research project, in which a field experiment of ethnic discrimination in the Norwegian labour market was complemented with forty‐two in‐depth interviews with employers who were observed in the first stage of the study. While the experimental data support earlier findings in documenting that ethnic discrimination indeed takes place, the qualitative material suggests that theorizing in the field experiment literature have been too concerned with individual and intra‐psychic explanations. Discriminatory outcomes in employment processes seems to be more dependent on contextual factors such as the number of applications received, whether requirements are specified, and the degree to which recruitment procedures are formalized. I argue that different contexts of employment provide different opportunity structures for discrimination, a finding with important theoretical and methodological implications.     

Anmerkungen zur Publikation „Möglichkeiten und Probleme des Einsatzes postalischer Befragungen“ von Karl-Heinz Reuband in der Kzfss 2001, 2, S. 307–333

Reuband’s article purports to report empirical results that seem to contradict the widely held view of mail surveys. This assertion is made possible only by an unclear statement of hypotheses and a selective perception of the literature. The data analysis is based on techniques from the 1960s and 1970s; modern methods are not even mentioned. Although all the results reported in the article are based on local surveys conducted by a university institute, these are generalized to national surveys in general. The main points of this critique are methodological: careless literature review, lack of concrete hypotheses, inefficient data analysis and generalizations without empirical foundation.     

Determinanten regelkonformen Verhaltens am beispiel des Strassenverkehrs

The main role of traffic police enforcement can be seen as preventing road users from committing offences, which can be related to road crashes and injuries. As the operating principle underlying the impact of police enforcement a deterrence effect has been discussed repeatedly, whereas from a sociological perspective the importance of “Norm Internalisation” has been emphasised. Thus, the present paper aims at comparing the influence of “Norm Internalisation” and the variables constituting the deterrence effect on the compliance with rules in road traffic. Based on a secondary analysis of data from a project on behavioural determinants of police surveillance carried out by the “Institute of Applied Transport and Tourism Research” (IVT) on behalf of the Federal Highway Research Institute (BASt) an operationalisation of the construct “General Norm Orientation” is developed. In several subsequent steps of statistical analysis patterns of correlations with variables from Opp’s “Theory of Law Obedience” are revealed. Results show a sufficiently high internal consistency (α = 0,82) of the scale “General Norm Orientation” and significant correlations with variables from Opp’s theory. The directions of these correlations are as expected and confirmed by multivariate analyses. Results are discussed with respect to their implications for influencing road users’ behaviours.     

The identification of logistic regression models with errors in the variables

The simple logistic regression model with normal measurement error and normal regressor is shown to be identifiable without any extra information about the measurement error. The multiple logistic regression model with more than one regressor variable measured with error is not identifiable. If the covariance matrix of the measurement error is known up to a scalar factor, the model is identified. Further we discuss why in spite of the identifiability the models cannot be estimated in a reasonable way without extra information about the measurement error.     

Beate Krais (Hg.): An der Spitze. Von Eliten und herrschenden Klassen

Ohne Zusammenfassung