Comparing variability of test scores across alternate forms, test conditions, or subpopulations is a fundamental problem in psychometrics. A confidence interval for a ratio of standard deviations is proposed that performs as well as the classic method with normal distributions and performs dramatically better with nonnormal distributions. A simple…

The present study examined whether in humans the generalized matching law described the relation between relative responding and relative drug intake by humans under concurrent variable interval variable interval (conc VI VI) schedules of drug reinforcement. Methadone-maintained patients, stabilized on 80 mg per day of methadone, were recruited…

Background: The extent to which abortion has harmful consequences for mental health remains controversial. We aimed to examine the linkages between having an abortion and mental health outcomes over the interval from age 15-25 years. Methods: Data were gathered as part of the Christchurch Health and Development Study, a 25-year longitudinal study…

Background: Verbal intrusion errors are irrelevant responses made in the course of verbal memory retrieval or language production that have been associated with disruption of executive functions and the prefrontal cortex. They have been observed to occur more frequently both with normal aging and with neurodegenerative diseases such as Alzheimer's…

Part of the history of oil and gas development on Indian reservations concerns potential underpayment of royalties due to under-valuation of production by oil companies. This paper discusses a model used by the Shoshone and Arapaho tribes in a lawsuit against the Federal government, claiming the Government failed to collect adequate royalties.…

A view on music within the framework depicted in this article will show, first of all, that music is part of the semiotically organized connections between living creatures. Music is universally present in human culture, and if music is, as Francis Sparshott says, a system of its own, with elements such as intervals, keys, and scales that are…

A data set contained in the "Journal of Statistical Education's" data archive provides a way of exploring regression analysis at a variety of teaching levels. An appropriate functional form for the relationship between percentage body fat and the BMI is shown to be the semi-logarithmic, with variation in the BMI accounting for a little over half…

The aims of this study were to characterize the spontaneous physical activity of children during school recess, and to estimate variation in physical activity associated with gender and age. A MTI actigraph (Model 7164) was used with a sample of 140 boys and 131 girls, 6 to 10 years of age. MTI counts were converted to METs using a regression…

This paper explores alternative approaches for facilitating efficient, evidence-centered item development for a new type of verbal reasoning item developed for use on the GRE® General Test. Results obtained in two separate studies are reported. The first study documented the development and validation of a fully automated approach for locating the…

Progress monitoring is a method of keeping track of children's academic development. Progress monitoring requires frequent data collection (i.e., weekly) with technically adequate measures, interpretation of the data at regular intervals, and changes to instruction based on the interpretation of child progress. This report presents two cases that…

Rats obtained food-pellet reinforcers by nose poking a lighted key. Experiment 1 examined resistance to extinction following single-schedule training with different variable-interval schedules, ranging from a mean interval of 16 min to 0.25 min. That is, for each schedule, the rats received 20 consecutive daily baseline sessions and then a session…

Five adult humans were tested for emergent conditional discriminations under rapid-responding contingencies. During four-comparison matching-to-sample baseline training (AB and AC), limited-hold contingencies for responding to samples and comparisons were gradually restricted to the shortest duration consistent with at least 95% accuracy and no…

This article talks about the approval given by the Education Department to 16 states that requested changes to accountability plans under the No Child Left Behind Act. Federal officials had sent decision letters to these states. Another 31 states are awaiting such letters, although many have received oral approvals or denials. This article…

This study looks at the syllable onset interval (SOI) patterning in Taiwan Mandarin spontaneous speech and its relationship to discourse and syntactic units. Monologs were elicited by asking readers to tell stories depicted in comic strips and were transcribed and segmented into Discourse Segment Units (Grosz & Sidner, 1986), clauses, and…

Fear extinction is defined as a decline in conditioned fear responses (CRs) following nonreinforced exposure to a feared conditioned stimulus (CS). Behavioral evidence indicates that extinction is a form of inhibitory learning: Extinguished fear responses reappear with the passage of time (spontaneous recovery), a shift of context (renewal), and…