Stimulus control of differential-reinforcement-of-low-rate responding

Five pigeons were given single-stimulus training on an 8-sec differential-reinforcement-of-low-rate schedule followed by steady-state generalization training using 12 wavelength stimuli. Three birds had a high percentage of reinforced responses on the training schedule and flat generalization gradients of total responses. The birds with fewer reinforced responses had much steeper generalization gradients. Generalization gradients plotted as a function of both stimulus wavelength and interresponse time showed that for most birds, stimulus control was restricted to responses with long interresponse times. Responses with very short interresponse times were not under stimulus control and there was some evidence of inhibitory control of short interresponse times. Interresponse-times-per-opportunity functions, plotted as a function of stimulus wavelength, showed that stimulus wavelength controlled the temporal distribution of responses, rather than the overall rate of response. The data indicate that the differential-reinforcement-of-low-rate schedule generates several response categories that are controlled in different ways by wavelength and time-correlated stimuli, and that averaging responses regardless of interresponse-time length obscures this control.     

Consequences of Ignoring Guessing Effects on Measurement Invariance Analysis

Pseudo-guessing parameters are present in item response theory applications for many educational assessments. When sample size is not sufficiently large, the guessing parameters may be ignored from the analysis. This study examines the impact of ignoring pseudo-guessing parameters on measurement invariance analysis, specifically, on item difficulty, item discrimination, and mean and variance of ability distribution. Results show that when non-zero guessing parameters are ignored from the measurement invariance analysis, item discrimination estimates tend to decrease particularly for more difficult items, and item difficulty estimates decrease unless the items are highly discriminating and difficult. As the guessing parameter increases, the size of the decrease in item discrimination and difficulty tends to increase, and the estimated mean and variance of ability distribution tend to be inaccurate. When two groups have heterogeneous ability distributions, ignoring the guessing parameter affects the reference group and the focal group differently. Implications of result findings are discussed.     

Assessing potential reinforcement-like effects of brief stimuli unrelated to food reinforcers

It is widely assumed that reinforcers are biologically relevant stimuli, or stimuli that have been associated with biologically relevant stimuli. However, brief, arbitrary stimuli have also been reported to have reinforcement-like effects, despite being unrelated to biologically relevant stimuli like food. The present study explored the potential reinforcement-like effects of brief stimuli across 5 experiments. In Experiments 1 through 4, pigeon subjects responded for food reinforcement and brief stimulus presentations in a 2-component multiple schedule. Neither baseline response rates nor resistance to change during disruption tests were systematically greater in a component with versus without brief stimulus presentations. Increasing the rate and duration of brief stimulus presentations in Experiment 4 did not reveal reinforcement-like effects when compared directly with food. In Experiment 5, pigeons chose between independent terminal links in a concurrent-chains procedure. Across conditions, varying the location, duration, and rate of brief stimulus presentations in the terminal links had no systematic effects on preference. In contrast, varying rates of food reinforcers resulted in large and reliable shifts in preference. Therefore, the present study found no systematic evidence that brief stimuli unrelated to food reliably increase response rates, resistance to change, or preference. These data demonstrate the value of systematic replication, and a behavioral momentum approach to assessing potential reinforcement-like effects.     

Inter-individual differences in intra-individual variability in personality within and across contexts

This study focuses on intra-individual variability in personality at work, and how it relates to job performance. 288 professionals completed contextualised adjective-based personality assessments in work and non-work contexts, and a non-contextualised personality measure. Ratings of their personality were also obtained from colleagues, family members and friends. Supervisors provided performance ratings for 130 participants. Results indicate that personality is context- and source-dependent, and varies systematically within contexts intra-individually regardless of source. Whilst this variability was predictive of some performance criteria when based on other-ratings, overall predictive effects were small in number and size. This study adds to the relatively small body of research on personality variability and performance and contributes to the conceptualisation of personality as a dynamic construct.     

Investigating How Test-Takers Change Their Strategies to Handle Difficulty in Taking a Reading Comprehension Test: Implications for Score Validation

This article investigates how test-takers change their strategies to handle increased test difficulty. An adult sample reported their test-taking strategies immediately after completing the tasks in a reading test. Data were analyzed using structural equation modeling specifying a measurement-invariant, ability-moderated, latent transition analysis in Mplus (Muthén & Asparouhov, 2011). It was found that almost half of the test-takers (47%) changed their strategies when encountering increased task-difficulty. The changes were characterized by augmenting comprehending-meaning strategies with score-maximizing and test-wiseness strategies. Moreover, test-takers' ability was the driving influence that facilitated and/or buffered the changes. The test outcomes, when reviewed in light of adjusted test-taking strategies, demonstrated a form of process-based validity evidence.     

Temperament,coping, and involuntary stress responses in preadolescent children: the moderating role of achievement goal orientation

Background and objectives: Developmental theorists posit that temperament contributes to preadolescent’s stress response styles. Findings from empirical studies, however, have yielded mixed results, thus indicating a need to consider moderators of this relation. Utilizing an analytic framework guided by resiliency theory [Zimmerman, M. A. (2013). Resiliency theory: A strengths-based approach to research and practice for adolescent health. Health Education &; Behavior, 40, 381–383], this study examined achievement goal orientation as a moderator of the relation between temperament and stress response styles.

Methods: 96 preadolescent–parent dyads (M_age?=?10.30 years, range?=?9–12 years) participated in the study. Preadolescents reported on their achievement goal orientation, coping and involuntary stress responses (ISRs) styles and a parent reported on children’s temperament.

Results: Multiple regressions revealed that effortful control positively predicted preadolescent’s predominant use of engagement coping and negatively predicted predominance of ISRs, but only for children with a predominant mastery goal orientation. For preadolescents with a predominant performance goal orientation, effortful control negatively predicted the predominant use of engagement coping and positively predicted predominance of ISRs. Negative affectivity and its interaction with goal orientation did not predict coping or ISR styles.

Conclusions: Findings suggest that a predominant mastery goal orientation may function as a promotive factor by enhancing the contribution of effortful control to engagement coping styles and buffering against unmanaged reactivity.