Row similarity in binary-valued matrices

An algorithm is developed for calculating the probability distribution of the number of matches between two specified rows of a matrix of zeroes and ones. Cases covered include row totals fixed, column totals fixed, and column totals and the two specified rows' totals fixed. The results are applied to presence-absence data on six species of ground finches on 23 Galàpagos islands and two constructed examples.     

Tests of odds ratio homogeneity with improved power in sparse fourfold tables

Some new tests of odds ratio homogeneity for fourfold tables are compared with the mixture model score test in the sparse-data case (many tables, small margins per table). Based on general empirical Bayes inequalities, the new tests have competitive power for 1:R matched designs, and superior power for more balanced designs.     

‘They follow the wants and needs of an institution’: Midwives’ views of water immersion

BackgroundA midwife’s ability to fully support women’s autonomy and self-determination with respect to midwifery care is often challenging. This is particularly true of water immersion for labour and birth. However, the woman’s agency over what happens to her body and that of her unborn baby should be key considerations for maternity care provision.ObjectivesA three phased mixed-methods study was undertaken to examine how water immersion policies and guidelines are informed. Phase three of this study captured the knowledge and experiences of Australian midwives, their support for water immersion and their experiences of using policies and guidelines to inform and facilitate the practice.MethodsCritical, post structural, interpretive interactionism was used to examine more than 300 responses to three open-ended questions included in a survey of 233 midwives. Comment data were analysed to provide further insight, context and meaning to previously reported results.FindingsFindings demonstrated a complex, multidimensional interplay of factors that impacted on both the midwife’s ability to offer and the woman’s decision to use water immersion under the themes ‘the reality of the system’, ‘the authoritative ‘others’’ and ‘the pseudo decision-makers’. Multiple scaffolded levels were identified, each influenced by the wider macro-socio-political landscape of Australian midwifery care.ConclusionsThe insight gained from examining midwives’ views and opinions of water for labour and birth, has aided in contextualising previously reported results. Such insight highlights the importance of qualitative research in challenging the status quo and working towards woman-centred practice and policy.     

Locally D-Optimal Design for a Logit Model in Discrete Choice Experiment

Conjoint analysis is concerned with understanding how people make choice between products or services (alternatives) or a combination of product and service (choice set), so that businesses can design new products or services that better meet customers needs. In this situation, logit model (Multinomial Logit Model) has been used to calculate the probability related to choosing an alternative in a choice set with the highest utility. Then I considered several choice sets instead of one. In this article, I have used the locally D-optimal design for the combination of the level of attributes (two attributes each with two levels) to create alternatives. The optimal combination of alternatives in choice sets which help us to have a suitable choice.     

Smooth bootstrap-based confidence intervals for one binomial proportion and difference of two proportions

Constructing confidence intervals (CIs) for a binomial proportion and the difference between two binomial proportions is a fundamental and well-studied problem with respect to the analysis of binary data. In this note, we propose a new bootstrap procedure to estimate the CIs by resampling from a newly developed smooth quantile function in [11 Newcombe, R. G. 1998. Two-sided confidence intervals for the single proportion: Comparison of seven methods. Stat. Med., 17: 857–872. (doi:10.1002/(SICI)1097-0258(19980430)17:8<857::AID-SIM777>3.0.CO;2-E)[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]] for discrete data. We perform a variety of simulation studies in order to illustrate the strong performance of our approach. The coverage probabilities of our CIs in the one-sample setting are superior than or comparable to other well-known approaches. The true utility of our new and novel approach is in the two-sample setting. For the difference of two proportions, our smooth bootstrap CIs provide better coverage probabilities almost uniformly over the interval (?1, 1), particularly in the tail region as compared than other published methods included in our simulation. We illustrate our methodology via an application to several different binary data sets.     

论刑事简易审判程序的变更权

我国立法明确规定:刑事简易审判程序的适用必须经被告人同意,被告人有选择适用简易审判程序的权利.但是,被告人选择了简易审判程序后能否反悔?大多数国家的法律对此问题做出了肯定的回答.我国的法律也规定,被告人可以选择变更简易审判程序,为了赋予被告人更完整的程序选择权,急需完善刑事简易审判程序的变更权.     

Loss Averse Behavior

A behavioral condition of loss aversion is proposed and tested. Forty-nine students participated in experiments on binary choices among lotteries involving small scale real gains and losses. At the aggregate level, a significant proportion of the choices are in the direction predicted by loss aversion. Individuals can be classified as loss averse (28 participants), gain seeking (12), and unclassified (9). A comparison with risk behavior for binary choices on lotteries involving only gains shows that risk attitudes vary across these domains of lotteries. A gender effect is also observed: proportionally more women are loss averse. In contrast to the predictions of comonotonic independence, the size of common outcomes has systematic influence on choice behavior. JEL Classification: D81, C91     

Simulation Games in Theory Development

Mathematics provides a set of tools and a language by which sociologists can precisely develop and express an abstract theory of society. Simulation games provide relatively limited and controlled contexts in which qualitative observations may suggest insights upon which to build systematic quantitative social theory. James Coleman was one of the strongest advocates for the use of simulation games in developing and communicating social theory; his Democracy game was a valuable tool in the development of his theory of collective action. In this paper, I provide an extended example of the use of observations of simulation games. My observations of two different games suggested ways to reconsider and revise certain aspects of rational choice theory. Building upon Herbert A. Simon's ([1957] Models of Man, Social and Rational: Mathematical Essays on Rational Human Behavior in a Social Setting, New York: Wiley) and John W. Thibaut and Harold H. Kelley's ([1959] The Social Psychology of Groups, New York: Wiley) theories of rationality in the context of incomplete information, my observations suggested that frustration behavior may be a rational response to the failure to meet expectations.     

Statistical inference for multiple change-point models

In this article, we propose a new technique for constructing confidence intervals for the mean of a noisy sequence with multiple change-points. We use the weighted bootstrap to generalize the bootstrap aggregating or bagging estimator. A standard deviation formula for the bagging estimator is introduced, based on which smoothed confidence intervals are constructed. To further improve the performance of the smoothed interval for weak signals, we suggest a strategy of adaptively choosing between the percentile intervals and the smoothed intervals. A new intensity plot is proposed to visualize the pattern of the change-points. We also propose a new change-point estimator based on the intensity plot, which has superior performance in comparison with the state-of-the-art segmentation methods. The finite sample performance of the confidence intervals and the change-point estimator are evaluated through Monte Carlo studies and illustrated with a real data example.