Children's fuzziness leads to increased variance in the data, data loss, and high dropout rates in developmental studies. This study investigated the importance of 20 factors on the person (child, caregiver, experimenter) and situation (task, method, time, and date) level for the data quality as indicated via the number of valid trials in 11…

This report presents a review of the statistical practices of 30 journals representative of the second language field. A review of 150 articles showed a number of prevalent statistical violations including incomplete reporting of reliability, validity, non-significant results, effect sizes, and assumption checks as well as making inferences from…

School practitioners and educators are frequently challenged by the diverse and pervasive academic and behavioral needs of children at risk for and with attention-deficit hyperactivity disorder (ADHD). This paper examines the outcome literature on self-regulated learning (SRL) interventions for youth with ADHD by systematically reviewing the key…

In experimental research, internal validity refers to what extent researchers can conclude that changes in dependent variable (i.e. outcome) are caused by manipulations in independent variable. The causal inference permits researchers to meaningfully interpret research results. This article discusses (a) internal validity threats in social and…

Purpose: The use of e-learning is largely predicated upon the assumption that it can facilitate improvements in student learning and therefore can be more effective than conventional techniques. This assumption has been supported by some in the literature but has been questioned by a continuing body of contrary or indifferent evidence. The purpose…

Research on perceptual and cognitive capacities of the newborn has revealed that state variables typically interfere with or override the neonate's attentional and stimulus processing tendencies. This finding argues for the power of early state variables as behavioral determinants and, further, that neonatal state measures might provide good…

Compares approaches to modeling ordinal outcome variables, including assumptions, interpretations, and limitations. Explores how the multiple regression approach with ordinal level data can compromise the understanding of the effects of the independent variables and of the ordinal level response. Provides applications with data from a multisite…

Obesity in children is a problem both insidious and acute. Childhood obesity has been indicated as a forerunner of adult obesity; it is also an immediate problem for the child. Given the lack of evidence for long term maintenance of any weight loss, this paper investigates the etiology of the disorder as a prelude to prevention. Upon review of the…

This paper examines facts and faults of some of the relevant research concerning abortion and its psychological effects. The paper notes that because of research design flaws, conclusions are tentative at best. However, it is concluded that research suggests or indicates: (1) women primarily experience relief and few negative psychological…

A meta-analysis of outcomes from 32 studies investigating pretest effects was conducted. For all outcomes the average effect size was +.22, indicating an elevating effect of pretest on posttest. Duration of time between pre- and posttesting was also related to effect size. Researchers should continue to include pretest as a design variable.…

It has been increasingly realized that (1) multivariate methods are essential in most quantitative studies (Fish, 1988; Thompson, 1992), and (2) all conventional parametric analytic methods are correlational and invoke least squares weights (e.g., the beta weights in regression) (Knapp, 1978; Thompson, 1991). The present paper reviews one very…

L. A. Marascuilo and R. C. Serlin (1988) note that stepwise regression is a method used frequently in social science research. C. Huberty (1989) characterizes such applications as being "common". In support of this latter statement, a review of dissertations by B. Thompson (1988) demonstrated that dissertation students frequently use…

Argues that, in the assessment of school "effects," multiple indicators of school effectiveness are required, including scholastic attainment, classroom behavior, absenteeism, attitudes to learning, continuation in education, employment, and social functioning. Assesses empirical evidence on the extent to which schools may be effective…

Reviews the existing literature on the perceptions, knowledge, and use of services by the elderly. Results suggest many elderly do not hold positive attitudes towards services, a bare majority appear aware of services, utilization rates are extremely low, and the correlates of service use are not well understood. (JAC)

Explores problems involved in the quantitative verification of independent variables in investigations of the effects on student outcomes of planned variations in instructional behavior. Specifically addresses (1) gathering of data through direct systematic observation, and (2) analysis of those data through the use of inferential statistics. (GC)