Pathways and transitions of gamblers over two years

Moderate-risk and problem gamblers represent 1.4% and 0.4% of the Québec population, respectively. Research on gamblers’ trajectories has been hampered by methodological shortcomings leading to heterogeneous results. The present research was conducted in the Province of Québec with a representative sample of adult gamblers and aims to explore how gamblers change over time according to the severity of their gambling problems. Using a 2-year follow-up prospective design (3 waves), 179 gamblers selected from a representative survey were divided into the 4 PGSI (Problem Gambling Severity Index) categories. Beyond the decreasing trend in PGSI scores detected within the overall sample using a linear growth model, our analyses revealed that moderate-risk gamblers are heterogeneous in their composition and evolution, comprising stable moderate-risk, recent cases and former problem gamblers. Over three waves, one-third of moderate-risk gamblers improved, one-third remained stable and one-third became problem gamblers. The subgroups transitioning in and out of the moderate-risk category differed in terms of reported changes in gambling behaviours and consequences. Problem gamblers remain vulnerable over time, being at risk of experiencing chronic problems. Results highlight the necessity of subgroup-specific prevention programmes and treatment services that address both the non-linearity of risky gambling and the chronicity of problem gambling.     

A process capability index with reliable confidence intervals

A well-know process capability index is slightly modified in this article to provide a new measure of process capability which takes account of the process location and variability, and for which point estimator and confidence intervals do exist that are insensitive to departures from the assumption of normal variability. Two examples of applications based on real data are presented.     

A note on deriving rank-dependent utility using additive joint receipts

Luce and Fishburn (1991) derived a general rank-dependent utility model using an operation ⊕ of joint receipt. Their argument rested on an empirically supported property (now) calledsegregation and on the assumption that utility is additive over ⊕. This note generalizes that conclusion to the case where utility need not be additive over ⊕, but rather is of a more general form, which they derived but did not use in their article. Tversky and Kahneman (1992), conjecturing that the joint receipt of two sums of money is simply their sum, criticized that original model because ⊕=+ together with additive utility implies the unacceptable conclusion that the utility of money is proportional to money. In the present generalized theory, if ⊕=+, utility is a negative exponential function of money rather than proportional. Similar results hold for losses. The case of mixed gains and losses is less well understood.     

Penalized contrast estimator for adaptive density deconvolution

The authors consider the problem of estimating the density g of independent and identically distributed variables X_I, from a sample Z₁,… Z_n such that Z_I = X_I + σ? for i = 1,…, n, and E is noise independent of X, with σ? having a known distribution. They present a model selection procedure allowing one to construct an adaptive estimator of g and to find nonasymptotic risk bounds. The estimator achieves the minimax rate of convergence, in most cases where lower bounds are available. A simulation study gives an illustration of the good practical performance of the method.     

THE CARING DILEMMA IN MIDWIFERY

The caring dilemma, first described by Reverby in 1987, denotes the tension caused by being obliged to provide care without the right to determine how that care is to be provided. Such a dilemma is salient in the practice of midwifery based on a continuity of care model that has recently emerged or been implemented in various jurisdictions. Briefly, this model involves the provision of care by a single midwife or pair of midwives to a woman throughout her pregnancy, birth and post-natal period. Continuity of care necessitates that midwives be on call for significant lengths of time to ensure attendance at the woman's birth. It is the on-call nature of this form of midwifery work that most significantly poses a caring dilemma for midwives. In this paper, we trace both the structural and experiential aspects of the caring dilemma through an examination of midwifery in the Canadian province of Ontario. Our analysis reveals that despite being a salient feature of midwifery practice, some work structures can be created to mediate the caring dilemma experienced by midwives.

Le dilemme de la prise en charge, que Reverby a évoqué la première fois en 1987, dénote la tension que cause le fait d’être tenu d'offrir une prise en charge sans avoir le droit d’établir de quelle manière l'offrir. L'exemple des sages-femmes, dont la pratique repose sur un type de soin continu qui est récemment apparu ou qu'on vient de mettre sur pied dans diverses administrations, illustre très clairement ce dilemme. Pour résumer, ce modèle veut qu'une femme enceinte soit prise en charge pendant sa grossesse, à son accouchement et durant sa période postnatale par une ou deux sages-femmes. La continuité de la prise en charge oblige les sages-femmes à être sur appel durant des périodes prolongées pour que la femme qui accouche bénéficie de leur présence. Pour les sages-femmes, c'est la nature même de leur travail effectué sur appel qui engendre, de façon cruciale, le dilemme de la prise en charge. Dans cet article, nous abordons les aspects structurels et expérimentaux que représente le dilemme de la prise en charge par le biais d'une étude sur la pratique du métier de sage-femme dans la province canadienne de l'Ontario. Notre analyse révèle que, si le dilemme de la prise en charge est inhérent à la profession de sage-femme, il n'empêche que des structures professionnelles peuvent être mises en place pour en atténuer les aspects négatifs.     

On time-irreversibility and other non-linear features in time series

Time-irreversibility, asymmetry of the distribution, and the occurrence of sudden bursts are considered, amongst others, as non-linear features in time series modeling. The implication is often made that time series showing these features must be analyzed using non-linear models. In contrast, this paper shows that time-irreversible asymmetric time series showing certain types of sudden bursts may be generated by linear models with adequate input sequences. Thus some non-linear time series features may be caused by the pattern in the input sequence rather than by non-linearity in the model. Examples are considered to illustrate the situation.     

Interpersonal comparisons of utility for 2 of 3 types of people

This article argues that there is a natural solution to carry out interpersonal comparisons of utility when the theory of gambles is supplemented with a group operation of joint receipts. If so, three types of people can exist, and the two types having multiplicative representations of joint receipt have, in contrast to most utility theories, absolute scales of utility. This makes possible, at least in principle, meaningful interpersonal comparisons of utility with desirable properties, thus resolving a long standing philosophical problem and having potentially important implications in economics. Two behavioral criteria are given for the three classes of people. At this point the relative class sizes are unknown.