A jack knife is a pocket knife that is put to many tasks, because it's ready to hand. Often there could be a better tool for the job, such as a screwdriver, a scraper, or a can-opener, but these are not usually pocket items. In statistical terms, the expression implies making do with what's available. Another simile, of an extreme situation, is…

This study serves as a teaching aid for teachers of introductory statistics. The aim of this study was limited to determining various sample sizes when estimating population proportion. Tables on sample sizes were generated using a C[superscript ++] program, which depends on population size, degree of precision or error level, and confidence…

This report provides a portrait of educational attainment in the United States based on data collected in the 2009 American Community Survey (ACS) and the 2005-2009 ACS 5-year estimates. It also uses data from the Annual Social and Economic Supplement (ASEC) to the Current Population Survey (CPS) collected in 2009 and earlier, as well as monthly…

We propose a nonparametric (or distribution-free) procedure for testing the equality of several population variances (or scale parameters). The proposed test is a modification of Bakir's (1989, Commun. Statist., Simul-Comp., 18, 757-775) analysis of means by ranks (ANOMR) procedure for testing the equality of several population means. A proof is…

The relationship between educational attainment and economic outcomes is shaped by a variety of educational experiences, including field of training, length of time spent in school, and level of attainment. This report explores the relationship between educational attainment, field of training, and eventual occupation and earnings. The report also…