A Score Test for the Multivariate Burr and Other Weibull Mixture Distributions

The p -variate Burr distribution has been derived, developed, discussed and deployed by various authors. In this paper a score statistic for testing independence of the components, equivalent to testing for p independent Weibull against a p -variate Burr alternative, is obtained. Its null and non-null properties are investigated with and without nuisance parameters and including the possibility of censoring. Two applications to real data are described. The test is also discussed in the context of other Weibull mixture models.     

Social theory’s “constituency”

The argument is made that the relation between theory and research has become tenuous in American sociology during the recent past, and that during the earlier decades of this century the nature of that relationship was different. A suggestion is made for the reacquaintance of empirical research and its theoretical underpinning. He wroteWeber, Irrationality, and Social Order, co-editedHermeneutics, edited and published the journalHistory of Sociology for some years, is now editor ofSociological Theory, and has moved to the University of California at Riverside. Please send all correspondence to: Alan Sica, Department of Sociology, University of California-Riverside, Riverside CA 92521-0419.     

On scale and scope and the history of the non-profit sector in the United Kingdom

This article argues that Alfred Chandler's analysis of the British firm cannot be transposed to the very different context of non-profit organisations in Britain. Both in relation to charitable non-profit organisations and mutual benefit organisations, Chandler's theory of the development of firms does not help explain organisational development. The main thrust of the argument is that the explanation for the smaller size of charitable non-profits in Britain than in America is largely institutional and partly socio-cultural; the explanation does not lie in any failure in Britain to adopt new techniques of management and organisation. With mutual benefit non-profits, a rather different account is presented. ‘Mutuals’ which had a strong fraternal element were relatively more successful in Britain than in America, although there is less difference between the two countries with regard to ‘non-fraternal’ mutuals. Once again, it is argued that institutional and socio-cultural factors—rather than the factors identified by Chandler—account for this. I wish to thank Desmond King for his helpful comments on an earlier version of this essay.     

Credit and blame in ethnographic publishing

The question of preserving anonymity in data presentation is more complicated than has usually been assumed. While the standard rule has been to disguise the names and identity of one’s research subjects in order to protect them from potential blame by associates and strangers, such a strategy also prevents them from receiving credit. Circumstances may exist in which the disguise of research subjects is undesirable, particularly with their informed consent. His special areas of interest are leisure behavior, qualitative methods and the sociology of art and culture.     

A Weibull-based score test for heterogeneity

The Weibull distribution is a natural starting point in the modelling of failure times in reliability, material strength data and many other applications that involve lifetime data. In recent years there has been a growing interest in modelling heterogeneity within this context. A natural approach is to consider a mixture, either discrete or continuous, of Weibull distributions. A judicious choice of mixing distribution yields a tractable and flexible generalization of the Weibull distribution. In this note a score test for detecting heterogeneity in this context is discussed and illustrated using some infant nutrition data.     

The ten commandments of writing

Whatever our areas and methods, social scientists share a common problem: how to write so as to foster communication. I present a set of propositions to lighten and brighten sociological writing. Sociologists ought not be afraid of using these tropes and techniques of literary writers. Each sociologist must develop a personal style that sparks an audience. Yet, this poses a challenge for those not trained. Writing is a craft that must be developed. As Wyndham Lewis noted: “It is dangerous to live, but to write is much more so.” He is the author ofTalking Sociology. Presented to the Annual Meeting of the Society for the Study of Symbolic Interaction, August 1987, Chicago, Illnois.