A method is presented for approximating the amount of bias in estimators with complex sampling distributions that are influenced by a variety of properties. The model is illustrated in the contexts of the bootstrap method and redundancy analysis. (SLD)

Compares 20 sets each of samples of four different sizes using simple random, constructed week, and consecutive day samples of newspaper content. Compares sample efficiency, and shows the superiority of constructed week sampling. (SR)

Several new multiple comparison procedures are discussed in terms of their applicability to the problem of generating confidence intervals based on range null hypotheses to control the familywise Type 1 error in multiple sample experiments. These procedures seem fairly robust to violations of normality and homogeneity assumptions. (SLD)

Describes MINSIZE, an MS-DOS computer program that permits the user to determine the minimum sample size needed for the results of a given analysis to be statistically significant. Program applications for statistical significance tests are presented and illustrated. (SLD)

Compares the costs and effectiveness of different recruitment strategies when a large and racially representative sample is needed, but specific requirements limit eligibility. Discusses common methods of social research recruitment, and evaluates five nonprobability sampling strategies. Discusses sample development when stratification is…

Illustrates that sampling variance can be very large when a three-wave quasi simplex model is used to obtain reliability estimates. Also shows that, for the reliability parameter to be identified, the model assumes a Markov process. These problems are evaluated with both real and Monte Carlo data. (SLD)

Presents an integrated mathematics and science activity in which students explore the concept of sampling on a soccer field. (ASK)

Effects of sample size and composition are systematically examined on the replicability of principal components, using observer ratings of personality from the California Adult Q-Set for 192 series of principal components analyses. Results indicate that dimensionality cannot be inferred from component robustness; they are empirically and logically…

Describes the process used to identify a rare sample of U.S. public secondary schools, those that are divided into "schools-within-schools" and provides descriptive information about the 55 schools of that kind that were found in a national search in fall 1998. Offers some tentative conclusions about the school-within-school reform approach. (SLD)

The authors used stratified random sampling procedures to investigate the relationships among physical activity (PA), the proximity of exercise facilities, and the quantity of home exercise equipment in a sample of 411 undergraduates. To examine the data they collected from the modified Godin Leisure-Time Exercise Questionnaire and the Home…

Rasch proposed an exact conditional inference approach to testing his model but never implemented it because it involves the calculation of a complicated probability. This paper furthers Rasch's approach by (1) providing an efficient Monte Carlo methodology for accurately approximating the required probability and (2) illustrating the usefulness…

Scientists use sampling to get an estimate of things they cannot easily count. A population is made up of all the organisms of one species living together in one place at the same time. All of the people living together in one town are considered a population. All of the grasshoppers living in a field are a population. Scientists keep track of the…

Language sample analysis measures have long been promoted as exhibiting greater ecological validity than formal testing in the assessment of language disorder in children. In practice, their use is often restricted to preschool children, owing to lack of normative information, as well as criticisms of the validity of commonly used measures for the…

Format dependence implies that assessment of the same subjective probability distribution produces different conclusions about over- or underconfidence depending on the assessment format. In 2 experiments, the authors demonstrate that the overconfidence bias that occurs when participants produce intervals for an uncertain quantity is almost…

Psychologists occasionally study eminent individuals, such as Nobellaureates, U.S. presidents, Olympic athletes, chess grandmasters, movie stars, and even distinguished psychologists. Studies using such significant samples may be differentiated along 7 distinct dimensions: qualitative versus quantitative, single versus multiple case, nomothetic…