Typically developing 2;6-year-olds who are bilingual in English and an additional language and who hear English 60% of the time or more, perform equivalently to their typically developing monolingual peers.

Monolingual infants are typically studied as a homogenous group and compared to bilingual infants. This study looks further into two subgroups of monolingual infants, monodialectal and multidialectal, to identify the effects of dialect-related variation on the phonological representation of words. Using an Intermodal Preferential Looking task, the detection of mispronunciations in familiar words was compared in infants aged 1;8 exposed to consistent (monodialectal) or variable (multidialectal) pronunciations of words in their daily input. Only monodialectal infants detected the mispronunciations whereas multidialectal infants looked longer at the target following naming whether the label was correctly produced or not. This suggests that variable phonological input in the form of dialect variation impacts the degree of specificity of lexical representations in early infancy.

To estimate the impact of linguistic distance on vocabulary development, which was the aim of Study 1, we needed to account for the effects of all situational factors that were known or suspected to shape bilingual development. This was achieved through a two-step analyses of the data from the 372 children whose Additional Language was 1 of our 13 target languages. PLAN OF ANALYSESIn the first step, analyses were conducted on variables already established within the literature as strong predictors of vocabulary size (relative amount of exposure to each language in child-directed speech and overheard speech, gender, and SES). Analyses were conducted initially in ANCOVAs (to include

Expert judgment is often exercised in situations in which multiple pieces of information are available and relevant in varying degrees. For example, a doctor may be attempting to diagnose the likely illness of a patient on the basis of symptoms, medical history, clinical examination, and results of imperfectly diagnostic tests, as well as relevant demographic information, such as gender, age, and occupation. To take another example, a personnel manager might be judging the suitability of a candidate for a position, taking into account work experience, qualifications, interview performance, and results of psychometric tests. These are examples of what are termed multicue judgments, where the various dimensions of information are the cues, whose values have particular and distinct instantiations for individual cases.What makes multicue judgment of psychological interest, as well as of practical importance, is the potential for bias when such judgments are made intuitively. If experts lack self-insight into the processes underlying these judgments, they may be unconsciously biased. For example, it may be contrary to law or company policy for the personnel manager to take into account age or gender in his or her decision making. If no explicit algorithm is followed, however, we may have nothing better than self-report from the decision maker to establish which cues were actually used and with what relative weighting. For this reason, a tradition of research based on social judgment theory was developed some years ago to capture the tacit policies that decision makers use when making multicue judgments. Social judgment theory has its origins in the psychology of Egon Brunswick and is rooted in the ecological approach to human cognition-specifically, by relating the way in which the available information is modeled by the environment, on the one hand, and by the judge, on the other. For the history of the theory, the reader is referred to Doherty and Kurz (1996) and, for details of the associated lens model methodology, to Cooksey (1996).Social judgment theory uses multiple linear regression to measure policies that are implicit in the judgments that people make-a technique known as policy capture. In such studies, participants-or judges-are asked to make wholistic judgments about a series of cases in which information about the same set of multiple cues is available. The implicit policy can then be inferred by performing a multiple linear regression analysis from the cues onto the judgments. The resulting beta weights tell us which cues influenced the judge and to what relative extent. In some studies, an objective criterion of correct performance is also available. In the case of personnel selection decisions, for example, we may be able to assess job performance at a later date. In a full lens model analysis, a second multiple regression is performed from the cues onto the criterion. A simplified (ignoring nonlinear and nonadditive aspects) version of the lens model equation is then given as follows: achievement = ...

Scale errors occur when young children seriously attempt to perform an action on an object which is impossible due to its size. Children vary substantially in the incidence of scale errors with many factors potentially contributing to these differences, such as age and the type of scale errors. In particular, the evidence for an inverted U-shaped curve of scale errors involving the child's body (i.e., body scale errors), which would point to a developmental stage, is mixed. Here we re-examine how body scale errors vary with age and explore the possibility that these errors would be related to the size and properties of children's lexicon. A large sample of children aged 18-30 months (N = 125) was tested in a scale error elicitation situation. Additionally, parental questionnaires were collected to assess children's receptive and expressive lexicon. Our key findings are that scale errors linearly decrease with age in childhood, and are more likely to be found in early talkers rather than in less advanced ones. This suggests that scale errors do not correspond to a developmental stage, and that one determinant of these errors is the speed of development of the linguistic and conceptual system, as a potential explanation for the individual variability in prevalence.