Social Work Teachers and Social Work Practice

Summary A survey was undertaken to discover the extent to which thosesocial work teachers who teach social work methods, continueto practise after they become educators. The results suggestthat not more than 25% do so, and many of these on only a tokenbasis. Most respondents however regarded such practice as animportant aide to the teaching of social work methods, althoughsome consider consultancy roles to be equally relevant. In nocases was such practice linked with research, and only exceptionallydid employers allow time explicitly for it. We outline fourdifferent bases on which teachers might practise, all of whichwere suggested by respondents, many of whom added personal notesto the questionnaire, indicating the extent to which this subjectis a matter of wide interest and concern     

THE EFFECT OF LEARNING ON THE MAKE/BUY DECISION

By including the effects of learning over time on both the production of components and their integration into complete products, we develop an engineering‐based model of outsourcing. This model provides an alternative explanation for much of what other outsourcing theories predict, as well as making several new predictions. In particular, we show that outsourcing decisions can create a path‐dependent outsourcing trap in which a firm experiences higher long‐run costs after an immediate cost benefit. We also describe conditions under which outsourcing a small fraction of component production may dominate either complete insourcing or complete outsourcing. Finally, we show that, with discounting, there is a convex, curvilinear relationship between the optimal outsourcing fraction and the rate of technological change.     

DIFFICULTIES WITH TESTING FOR CAUSATION*

This paper examines the use of econometric tests for causality that are based on the work of Granger and Sims. The main conclusion is that it is not possible to infer the direction of causation from observed correlations. There are two reasons why the causality tests cannot reveal the direction of causation from observed correlations. First, the null hypothesis tested is necessary but not sufficient to imply causality. Second, any specification error renders the causality test results uninterpretable.     

FREEDOM, ECONOMIC OPPORTUNITY, AND FERTILITY: BLACK AMERICANS, 1860–1910

Black fertility declined sharply following Reconstruction. Demographers argue that explanations of post-bellum white fertility behavior are inapplicable to blacks. This paper hypothesizes that the reduced fertility was due to economic factors. An economic model of fertility is developed and estimated econometrically; it is consistent with the fertility experience of both races. It is concluded that several products of emancipation, including urbanization, increased literacy levels, and a shift in the economic burden of child maintenance from the slave owner to the family, were instrumental in increasing the opportunity cost of black children to their parents.     

ARE THERE BELLWETHER ELECTORAL DISTRICTS?

Using election returns from all U.S. counties for 14 presidentialelections, this study investigates the utility of election forecastingbased on "bellwether" or "barometric "electoral districts.     

THE GRAVITY MODEL: AN ILLUSTRATION OF STRUCTURAL ESTIMATION AS CALIBRATION

Dawkins, Srinivasan, and Whalley (“Calibration,”Handbook of Econometrics, 2001) propose that estimation is calibration. We illustrate their point by examining a leading econometric application in the study of international and interregional trade by Anderson and van Wincoop (“Gravity with Gravitas: A Solution to the Border Puzzle,”American Economic Review, 2003). We replicate the econometric process and show it to be a calibration of a general equilibrium model. Our approach offers unique insights into structural estimation, and we highlight the importance of traditional calibration considerations when one uses econometric techniques to calibrate a model for comparative policy analysis. (JEL F10, C13, C60)     

Motherhood under twenty: prevailing ideologies and research

SUMMARY. Women who become mothers under the age of 20 are usually thought to he at greater risk of health and social problems. The authors argue that such a prevailing view has become institutionalised in the approaches of practitioners and researchers. They examine the ideological and factual bases of such an attitude towards teenage mothers and conclude that ideology is dominant. Suggestions are made as to how this might be overcome to allow a more balanced approach to research about young motherhood.