Developmental differences in baserate estimates of social behaviors and attitudes

This study examined the development of baserate estimation skills for everyday social events and attitudes. Subjects in grades one, three, and six responded to questions concerning their own rates of behavior and attitudes, and their estimates of baserates of behaviors and attitudes for their classmates. The findings indicate a general increase in accuracy for the estimation of baserates throughout the elementary school years. In addition, younger subjects were less likely to make similar estimates for themselves and their classmates than were older respondents. Developmental changes in estimation accuracy are discussed in relation to task content, use of the response scale, correspondence between self-reports and estimates, and sample variability.     

Scrambled randomized response methods for obtaining sensitive quantitative data

We study a multiplicative randomized response method for obtaining responses to sensitive questions when the answers are quantitative. The method involves the respondent multiplying his sensitive answer by a random number from a known distribution, and giving the product to the interviewer, who does not know the value of the random number and thus receives a scrambled response. Some particular distributions for the random scrambling number are proposed and studied, and ways of generating the scrambling numbers are discussed. Some modifications for increasing the efficiency of the method are proposed, and numerical results are given that show the scrambled response method is generally superior to the previously used method of randomizing questions.     

Fast Mapping but Poor Retention by 24‐Month‐Old Infants

Four experiments explored the processes that bridge between referent selection and word learning. Twenty‐four‐month‐old infants were presented with several novel names during a referent selection task that included both familiar and novel objects and tested for retention after a 5‐min delay. The 5‐min delay ensured that word learning was based on retrieval from long‐term memory. Moreover, the relative familiarity of objects used during the retention test was explicitly controlled. Across experiments, infants were excellent at referent selection, but very poor at retention. Although the highly controlled retention test was clearly challenging, infants were able to demonstrate retention of the first 4 novel names presented in the session when referent selection was augmented with ostensive naming. These results suggest that fast mapping is robust for reference selection but might be more transient than previously reported for lexical retention. The relations between reference selection and retention are discussed in terms of competitive processes on 2 timescales: competition among objects on individual referent selection trials and competition among multiple novel name–object mappings made across an experimental session.     

The Single-Parent Family in Australia: An Overview

Studies of single-parent families in Australia are reviewed and statistical trends related to this type of family pattern are discussed. It is quite evident that family sociology has paid little attention to this growing population in Australia. The categories reviewed include single parents, unmarried mothers, widows, deserted wives and the families of prisoners.     

"毛主义"战略的基本特征

"毛主义"的基本内涵是在一个以农民为主体的社会结构中,按照列宁主义组织原则,建立一个由于信仰马克思列宁主义的若干基本准则而充满活力的政党。因而,这一思想体系就有异干以工人阶级为主体的苏联布尔什维克主义。毛泽东思想也因其鲜明的思想创造性,成为东方马列主义的独立流派。     

The probability of degenerate maximum-likelihood estimates with randomly truncated survival data

We study the nonparametric maximum-likelihood estimator of the marginal distribution function in bivariate data with truncated sum (Woodroofe 1985), and calculate the probability that it will assign zero probability to a range of observed values. We show that in a simple artificial model with uniform intensity in both variables the probability may be expressed using recursive formulae, and that large-sample approximations valid under weak regularity conditions show good agreement with as few as 20 observations. In the uniform-intensity model, the probability of degenerate estimates is rather small, being just over 5% with a dataset of 20 observations and falling below 1% with 125 observations. However, in a model of transfusion-associated AIDS in 125 children and adults (Kalbfleisch and Lawless 1989), the probability of degenerate estimates is much larger—about 30% with 20 observations and 3% with the actual 125 observations. This is largely because both the infection and incubation density are increasing over time. Such a pattern makes the condition for degeneracy, i.e., relatively high observed intensity at extreme values of each variable, much more likely.