Inside two commercially available statistical expert systems

A decade of research into the applications of artificial intelligence in statistics has finally resulted in the appearance of commercially available statistical expert systems. This paper takes a closer look at two of these systems, which are now commercially available on microcomputers, and shows what knowledge they actually contain and how they operate. It is concluded that although the technology and concepts that drive these systems could still benefit from further improvement, the real challenge lies in defining and constructing the statistical knowledge and strategy that should be incorporated and in presenting the results to the user's full advantage.     

Far-sighted equilibria in 2 × 2, non-cooperative,repeated games

Consider a two-person simultaneous-move game in strategic form. Suppose this game is played over and over at discrete points in time. Suppose, furthermore, that communication is not possible, but nevertheless we observe some regularity in the sequence of outcomes. The aim of this paper is to provide an explanation for the question why such regularity might persist for many (i.e., infinite) periods.Each player, when contemplating a deviation, considers a sequential-move game, roughly speaking of the following form: if I change my strategy this period, then in the next my opponent will take his strategy b and afterwards I can switch to my strategy a, but then I am worse off since at that outcome my opponent has no incentive to change anymore, whatever I do. Theoretically, however, there is no end to such reaction chains. In case that deviating by some player gives him less utility in the long run than before deviation, we say that the original regular sequence of outcomes is far-sighted stable for that player. It is a far-sighted equilibrium if it is far-sighted stable for both players.     

Gambling and the Law®: Endless fields of dreams

This article examines the current trends of proliferation of commercial gaming, especially in the United States, in the context of the third wave of legalization of gambling that has been experienced since the founding of the nation. The author looks at the historic foundations of the spread of casino-style gambling, and notes the types of casino gaming that have led the way in the current expansion. He also points out why it is reasonable to expect that this wave too may come crashing down, as general acceptance of wide-spread casino gaming in America may indeed be short-lived.Gambling and the Law^® is a registered trademark of I. Nelson Rose.     

The birth of the queen/the modern homosexual: historical explanations revisited

In this paper I review a number of explanations for the emergence of the modern homosexual category in Western (mainly Northwest European) cultures. I suggest there are four different emphases in respect of the social and cultural factors given priority in interpretations of the formation of the homosexual category. Of course, individual studies have often taken into consideration more than one single factor (most notably, Greenberg, 1988; Chauncey, 1994), and the grouping of previous studies that I here suggest only indicates where the focus of a given study is. The social and cultural factors emphasized in these four approaches are: 1) the effects of competitive capitalism on the bourgeois/middle class political economy of sexuality and sexual morals; 2) the rise of expert knowledges, controlling systems, and modern bureaucracies; 3) tensions within gender order and the struggle over new definitions of gender roles; 4) the rise of free wage labour, the proliferation of urban anonymity, and the unfolding of new modes of existence in the life-world of modern pluralist urban society. Finally, the article briefly considers the potential erosion of the homosexual vs. heterosexual divide in the light of the historical background. Almost thirty years have passed since ‘The Homosexual Role’, by Mary McIntosh (1968), the first notable contribution to the historical sociology of homosexuality operating within a social constructionist view of homosexuality. Since then, there have been numerous studies of the formation of the conceptual category and social aggregate of ‘modern homosexual’. Researchers have differed about whether the pedigree of ‘homosexual’ and homosexual identities and subcultures in Western societies can be traced back to the late nineteenth century or to the early eighteenth century, and whether or not some notion of ‘homosexual’ was established in the cultural imagery before the last fifty years or so. It might be fruitful to distinguish between the historically older categories of ‘molly’, ‘queen’, and ‘fairy’ on the one hand, and the more recent ‘homosexual’ on the other hand. It can be argued that the decisive feature of the first-mentioned ‘deviant men’ was their status as gender-crossers (which as a side-effect entailed an interest in homosexual conduct), whereas the modern term homosexual does not necessarily suggest gender-crossing or more generic ‘sexual inversion’(cf. Chauncey, 1994). However, allusions to gay men's purported effeminacy and lesbian women's purported masculinity continue to surface frequently also in contemporary culture. Hence, for the sake of brevity, I here use the term modern homosexual, by which I refer to a notion that there is in some people an inherent sexual desire exclusively for persons of the same sex, and that this so-called sexual orientation is to some degree intertwined with a tendency to gender-crossing conduct. ¹ 1 Historically there has been a mutually re-enforcing dynamics between the forma-tion of the conceptual category and the social aggregate of homosexual(s). Methodological considerations and also certain presumptions about the dynam-ics of culture and society help explain why, until recently, most studies have focused on the trajectory of concepts, identities, and social roles, rather than on the experiential, embodied aspects of the social aggregate of homosexual(s). The idea of sexual inversion predicates that homosexual desire is evidence of a faulty combination of body and soul: there is ‘a female soul in a male body’, or vice versa. On the distinctions between sexual orientation and sexual role see, King, 1984.
     

The Development of Object Construction From Infancy Through Toddlerhood

Early in development, children explore and combine objects in increasingly complex ways. One manual skill, object construction, represents a major shift in how objects are explored relative to other objects. Despite recent connections with cognitive functioning such as spatial skills, the development of object construction ability has rarely been studied and its trajectory has not been adequately described. The purpose of this study was to describe the development of three types of object construction (stacking, nesting, and affixing) across 5 monthly infant visits and 7 monthly toddler visits using a longitudinal design and a large sample size. Infants (10–14 months, n = 131) and toddlers drawn from the infant sample (18–24 months, n = 65) were given sets of age‐appropriate toys each of which elicited at least one type of constructive play. We described success at different construction tasks and identified trends for construction skill for infant and toddler development using multilevel modeling. We found that each of the three construction actions developed in unique ways across the 10‐ to 24‐month period. Infant construction skill predicted the development of toddler skill, but toddler construction skill diverged from infant trajectories. We discuss the role of combination strategies in the development of object construction skill and how object construction could be related to other domains of development.     

An omnibus lack of fit test in logistic regression with sparse data

The usefulness of logistic regression depends to a great extent on the correct specification of the relation between a binary response and characteristics of the unit on which the response is recoded. Currently used methods for testing for misspecification (lack of fit) of a proposed logistic regression model do not perform well when a data set contains almost as many distinct covariate vectors as experimental units, a condition referred to as sparsity. A new algorithm for grouping sparse data to create pseudo replicates and using them to test for lack of fit is developed. A simulation study illustrates settings in which the new test is superior to existing ones. Analysis of a dataset consisting of the ages of menarche of Warsaw girls is also used to compare the new and existing lack of fit tests.     

Horses and baseball: social work’s cultivation of one’s ‘third eye’

Active self-reflection is a sophisticated and subtle, multi-layered process that requires learning the capacity to constantly self-monitor. These fundamental interactive skills, the core of a competent social worker, are important to work in any context. Using two distinct metaphors, one relating to horses, the other to baseball, the article will explore the importance of developing competency skills and utilize a ‘third eye.’ In current social work education curricula the use of self may not be prioritized, practiced, or well understood. Evidence from human and veterinary medicine as well as social work, are discussed. An example of an undergraduate BSW course using simulated clients and standardized measures is discussed. The paper includes a brief review of the preliminary findings for a small pilot study and the relevance to future research is considered.     

Scanner Data and the Treatment of Quality Change in Nonrevisable Price Indexes

The recently developed rolling year GEKS procedure makes maximum use of all matches in the data to construct nonrevisable price indexes that are approximately free from chain drift. A potential weakness is that unmatched items are ignored. In this article we use imputation Törnqvist price indexes as inputs into the rolling year GEKS procedure. These indexes account for quality changes by imputing the “missing prices” associated with new and disappearing items. Three imputation methods are discussed. The first method makes explicit imputations using a hedonic regression model which is estimated for each time period. The other two methods make implicit imputations; they are based on time dummy hedonic and time-product dummy regression models and are estimated on bilateral pooled data. We present empirical evidence for New Zealand from scanner data on eight consumer electronics products and find that accounting for quality change can make a substantial difference.     

RISK AVERSION AND OVERBIDDING IN FIRST PRICE SEALED BID AUCTIONS: NEW EXPERIMENTAL EVIDENCE

Bidding above the risk‐neutral Nash equilibrium in first price sealed bid auctions has traditionally been ascribed to risk aversion. Later studies, however, offer other explanations and even argue that risk aversion plays no or a minor role. In a novel experimental design, we directly test the relationship between risk aversion and overbidding by systematically varying the distribution of risk attitudes in auction markets. We find a significant relationship between our measure of risk aversion and overbidding. (JEL D44, C91)