Estimation in capture–recapture models when covariates are subject to measurement errors and missing data

For capture–recapture models when covariates are subject to measurement errors and missing data, a set of estimating equations is constructed to estimate population size and relevant parameters. These estimating equations can be solved by an algorithm similar to the EM algorithm. The proposed method is also applicable to the situation when covariates with no measurement errors have missing data. Simulation studies are used to assess the performance of the proposed estimator. The estimator is also applied to a capture–recapture experiment on the bird species Prinia flaviventris in Hong Kong. The Canadian Journal of Statistics 37: 645–658; 2009 © 2009 Statistical Society of Canada     

Modelling udder infection data using copula models for quadruples

We study copula models for correlated infection times in the four udder quarters of dairy cows. Both a semi-parametric and a nonparametric approach are considered to estimate the marginal survival functions, taking into account the effect of a binary udder quarter level covariate. We use a two-stage estimation approach and we briefly discuss the asymptotic behaviour of the estimators obtained in the first and the second stage of the estimation. A pseudo-likelihood ratio test is used to select an appropriate copula from the power variance copula family that describes the association between the outcomes in a cluster. We propose a new bootstrap algorithm to obtain the p-value for this test. This bootstrap algorithm also provides estimates for the standard errors of the estimated parameters in the copula. The proposed methods are applied to the udder infection data. A small simulation study for a setting similar to the setting of the udder infection data gives evidence that the proposed method provides a valid approach to select an appropriate copula within the power variance copula family.     

Operational challenges in adaptive design implementation

Implementation of adaptive clinical trial designs raises challenges with regard to the processes by which accruing trial data is analyzed, reviewed, and acted upon. In line with current monitoring conventions, it should be viewed that inappropriate knowledge of interim results can raise concerns regarding maintaining trial integrity and interpretability of results. Here we discuss issues related to these processes in adaptive trials, and point out distinctions versus other more familiar monitoring situations. One topic involves the composition of the group of individuals who will have access to interim results in order to recommend adaptations. We discuss operational models for data review by this group; one question addressed is whether in adaptive trials a role in this process for a representative of the study sponsor could at times be warranted, and might be justified if adequate protections are in place. Another issue involves whether adaptations made based upon interim data can convey to observers an amount of information about the results, which could rise to a level of concern. We consider whether different types of adaptations might be more or less problematic with regard to this issue, and recommend steps that might be considered to mitigate this concern.     

Feeling and finding on the register of suggestion: reflections on the 'event' of researching community mental health care

The paper posits an intervention in current debates around 'method making' in the social sciences, drawing on the experience of undertaking an ethnographic study of a community mental health team in East London. Theoretical recourse is made to the process philosophy of A.N. Whitehead and to the enduring provenance of the problem of 'suggestion' in the history of medicine and psychology. These offer rich and provocative theoretical resources with which to rethink the interpenetration of subject and object and 'feeling' and 'finding'. Whitehead's work provides a general philosophical framework whereby the ongoing subjective experience of the researcher can no longer be sharply demarcated from the 'data' encountered. Meanwhile the adoption of a 'register of suggestion' opens up insights into the inevitably selective and singular character of any given methodological procedure. It maintains the importance of affective factors at the forefront of analysis, and brings into focus the parts played by indeterminacy and risk in the research event.     

The Gender Pay Gap in the US: Does Sector Make a Difference?

Analyses of data from the 2000 US Census show that the gender pay gap differs by sector of employment and according to the part of the earnings distribution that is considered. The gender pay differential in the private sector in the US does not display either the glass ceiling or sticky floor effects that have been reported for many other countries. The government sector is, however, characterized by a distinct sticky floor effect in the female–male pay differential. Regardless of the sector of employment, females have lower hourly rates of pay than men across the entire earnings distribution.

Infants' Processing of Featural and Configural Information in the Upper and Lower Halves of the Face

Three‐ to 4‐month‐old and 6‐ to 7‐month‐old infants were administered an infant version of the Face Dimensions Test that has been used with adults (e.g., Bukach, Le Grand, Kaiser, Bub, & Tanaka, 2008). Infants were familiarized with a photograph of a woman's face and then tested with the familiar face paired with a face differing in the (a) distance separating the eyes (a configural/eyes change), (b) distance between the nose and mouth (configural/mouth change), (c) size of the eyes (featural/eyes change), and (d) size of the mouth (featural/mouth change). Infants were shown to be more sensitive to (a) configural than featural change, and (b) change around the eyes versus the mouth. Implications for the development of face processing are discussed.     

Who cares and how much: exploring the determinants of co-residential informal care

The importance of informal care provided inside the household (co-residential care) is widely acknowledged in policy circles. However, the factors that determine the likelihood and scale of provision are not fully understood. A two-part model (2PM) is used to investigate both participation and levels of provision. Random effects dynamic panel specifications are employed. Results show that co-residential informal care competes with other time demanding activities, such as childcare and employment. Wealthier individuals are less likely to be caregivers, whereas wealthier households have a higher tendency towards caregiving. Evidence of both substitution and complementarity is found between formal and informal care. Informal care and health status are significantly related, with carers more likely to report worse General Health Questionnaire scores than non-carers. Finally, significant dynamic effects are observed with the continuance of the provision of informal care being more likely than the initiation of such activity, while heavy commitment in the past increases the hours provided in the current period.