AGE,TIME, VINTAGE,AND PRICE INDEXES: MEASURING THE DEPRECIATION PATTERN OF HOUSES

Age, time, and vintage are key determinants of house prices, yet they cannot be included together linearly or as dichotomous variables in hedonic regressions as construction time + age of house = sale time. We introduce a method where the estimates of the age, time, and vintage effects on prices are obtained in a flexible manner, without requiring us to specify a pre‐determined functional form for any of these variables. Applying our method to Dutch data, we find that the estimated depreciation pattern over the life of houses does not follow the functional forms typically specified for the age of houses in hedonic regressions. (JEL C43, E01, E31, R31)     

Implemented as intended? Recording family worker activities in a Families First program

In evaluating family preservation services, it is important not only to study the service outcomes and the family characteristics, but also what actually happens during the treatment. This requires a program model. This article describes how a program model works, prescribes how workers should carry it out, and describes how researchers should measure the program's characteristics. The authors use data from Families First in The Netherlands to test the model. Results show that the method of the program meets the specified characteristics. The results are important for treatment, policy, education, and evaluation research.     

Können Organisationen nicht lernen? Facetten organisationaler Lernkulturen

Recently, the concept of ‘learning culture’ has entered the discussion on learning organizations and organizational learning, especially in the German speaking countries. Most of the academics, but also practitioners seem to use the term ‘learning culture’ in a particular sense as nurturing a self-directed, on-the-job learning of all employees. An implicit, often neglected assumption of this conception is that organizations can be divided into those who have a learning culture and those who do not. Although this idea of a dichotomy is also found in the discussion on learning organizations, it can be called into question. Past research has shown that (organizational) learning is a multifaceted phenomenon. Different organizations engage in very diverse kinds of learning due to the fact that they are facing varying environmental conditions. This brings us to doubt the idea of a ?one-best-way“ learning culture. Following the basic question, who learns what, how, when and why, the article presents a set of distinguishing attributes to distinguish between different types of learning cultures. Finally, yet unanswered questions and paths for future research are discussed.     

Voice and Identity in a Bicultural/Bilingual Environment

Researchers have noted that with the onset of adolescence, girls' voices become muted and school achievement drops. Girls learn that the expression of strong feelings leads to distance from others, and that full use of their bodies and minds cause others discomfort. Self-esteem suffers and girls become at risk for destructive behaviors. Most studies have been done with middle class Caucasian girls. Those few studies done with young girls of color speak of girls on the margin who seem to resist losing their voices and their self-esteem. This article describes a study involving 5th–8th grade girls participating in an Advisory group program at a grammar school in a predominantly Mexican community of a large city. Group sessions were taped and analyzed for common themes including voice and self-esteem. Focus was directed to the influence of the bicultural/bilingual environment in analysis of group content. Implications for practice are included.     

Covariate Order Tests for Covariate Effect

A new approach for constructing tests for association between a random right censored life time variable and a covariate is proposed. The basic idea is to first arrange the observations in increasing order of the covariate and then base the test on a certain point process defined by the observation times. Tests constructed by this approach are robust against outliers in the covariate values or misspecification of the covariate scale since they only use the ordering of the covariate. Of particular interest is a test based on the Anderson-Darling statistic. This test has good power properties both against monotonic and nonmonotonic dependencies between the covariate and the life time variable.     

An individual-based model for competingDrosophila populations

An individual-based model forDrosophila is formulated, based on competition amongst larvae consuming the same batch of food. The predictions of the model are supported by data for single speciesDrosophila populations reared in the laboratory. The model is used to build a simple discrete model for the dynamics ofDrosophila populations that are kept over a number of generations. The dynamics of a single species is shown to give either a stable equilibrium or fluctuations which can be periodic or chaotic. When the dynamics of a species in the absence of the other is periodic or chaotic, we found coexistence or two alternative states, on neither of which the species can coexist.