The ratio bias phenomenon: fact or artifact?

The ratio bias—according to which individuals prefer to bet on probabilities expressed as a ratio of large numbers to normatively equivalent or superior probabilities expressed as a ratio of small numbers—has recently gained momentum, with researchers especially in health economics emphasizing the policy importance of the phenomenon. Although the bias has been replicated several times, some doubts remain about its economic significance. Our two experiments show that the bias disappears once order effects are excluded, and once salient and dominant incentives are provided. This holds true for both choice and valuation tasks. Also, adding context to the decision problem does not alter this finding. No ratio bias could be found in between-subject tests either, which leads us to the conclusion that the policy relevance of the phenomenon is doubtful at best.     

‘Speak roughly to your little boy’? Sex Differences in the Relations Between Parenting and Preschoolers’ Understanding of Mind

The present study explores relations between young children's understanding of mind and parental emotional expression and disciplinary style, along with gender differences in these relations. Participants were recruited from a study of 125 same-sex twin-pairs (58% female; group mean age 5 43 months, SD 5 1 month). Each child received a comprehensive set of theory-of-mind tasks, and was filmed at home for 20 minutes in dyadic interactions with the primary caregiver, who was also interviewed about disciplinary strategies. Ratings of discipline and positive and negative parental affect and control were made from direct observation, from the interview, and from the videoed interactions. Strong correlations were found between family SES, parenting measures, and child verbal IQ and theory-of-mind score. However, regression analyses showed that parental behaviours were significant predictors of children's theory-of-mind performance, even when sex, verbal IQ and family SES were taken into account. Sex differences in these relations were also identified; parental affect was especially salient for understanding of mind in girls, while discipline was more salient for boys. Taken together, these findings highlight the importance of individual differences in the proximal processes associated with early understanding of mind, and suggest that development in mental-state awareness is associated with distinct aspects of parenting for girls and boys.     

Acknowledgements

This article explores whether it is possible to understand the perspectives of people with whom we find it difficult or impossible to empathise, because their moral and political views are very different to our own. Focusing on our dilemmas in carrying out qualitative research with conservative evangelicals and anti‐abortion activists, we take issue with the assumption that understanding is connected with the presence of rapport and empathy in research interviews. This article argues instead that a reflexive approach, which considers researchers’ orientations towards their subject and their respondents and their emotional journeys through the research process, will enable more comprehensive interpretation of our research material.     

'The Tip of the Ice Berg': Children's Complaints and Advocacy in Wales--An Insider View from Complaints Officers

This paper is based on findings of a Welsh Assembly Governmentfunded review of children’s independent advocacy servicesin Wales with reference to their involvement in complaints madeby children, or by their parents or carers on their behalf,about local authority social services. It draws, primarily,upon qualitative interviews with local authority children’scomplaints officers, whose task is to receive complaints orconcerns, field these to appropriate social services staff,maintain oversight of their progression and keep complainantsinformed of developments. The paper describes the challengesthat complaints officers perceive children encounter in movingcomplaints forward, especially in a context where independentadvocacy services are involved and where these services areviewed with some suspicion by social services staff. It suggeststhat complaints officers play a pivotal part in managing thesometimes contested and complex interface between service providerand child and may do so from a position of limited authorityand influence. The role of complaints officers in engaging withcomplainants and their advocates, and with those colleaguesimplicated in complaints, has rarely been the topic of research.This paper provides accounts from these key staff that helpilluminate the tensions and difficulties that can enter thechildren’s complaints process.     

Multistage Models of Carcinogenesis: An Approximation for the Size and Number Distribution of Late-Stage Clones

Multistage models have become the basic paradigm for modeling carcinogenesis. One model, the two-stage model of carcinogenesis, is now routinely used in the analysis of cancer risks from exposure to environmental chemicals. In its most general form, this model has two states, an initiated state and a neoplastic state, which allow for growth of cells via a simple linear birth-death process. In all analyses done with this model, researchers have assumed that tumor incidence is equivalent to the formation of a single neoplastic cell and the growth kinetics in the neoplastic state have been ignored. Some researchers have discussed the impact of this assumption on their analyses, but no formal methods were available for a more rigorous application of the birth-death process. In this paper, an approximation is introduced which allows for the application of growth kinetics in the neoplastic state. The adequacy of the approximation against simulated data is evaluated and methods are developed for implementing the approximation using data on the number and size of neoplastic clones.     

On-line bin packing with restricted repacking

Semi-on-line algorithms for the bin-packing problem allow, in contrast to pure on-line algorithms, the use of certain types of additional operations for each step. Examples include repacking, reordering or lookahead before packing the items. Here we define and analyze a semi-on-line algorithm where for each step at most k items can be repacked, for some positive integer k. We prove that the upper bound for the asymptotic competitive ratio of the algorithm is a decreasing function of k, which tends to 3/2 as k goes to infinity. We also establish lower bounds for this ratio and show that the gap between upper and lower bounds is relatively small.