Adaptive Equilibrium Regulation: Modeling Individual Dynamics on Multiple Timescales

Damped Linear Oscillators estimated by 2nd-order Latent Differential Equation have assumed a constant equilibrium and one oscillatory component. Lower-frequency oscillations may come from seasonal background processes, which non-randomly contribute to deviation from equilibrium at each occasion and confound estimation of dynamics over shorter timescales. Boker (2015) proposed a model of individual change on multiple timescales, but implementation, simulation, and applications to data have not been demonstrated. This study implemented a generalization of the proposed model; examined robustness to varied timescale ratios, measurement error, and occasions-per-person in simulated data; and tested for dynamics at multiple timescales in experience sampling affect data. Results show small standard errors and low bias to dynamic estimates at timescale ratios greater than 3:1. Below 3:1, estimate error was sensitive to noise and total occasions; rates of non-convergence increased. For affect data, model comparisons showed statistically significant dynamics at both timescales for both participants.     

Encoding of spatial information in images of an outdoor scene by pigeons and humans

Pigeons and adult humans searched for a 2-cm² unmarked goal in digitized images of an outdoor scene presented on a touch-screen monitor. In Experiment 1, the scene contained three landmarks near the goal and a visually rich background. Six training images presented the scene from different viewing directions and distances. Subsequent unreinforced tests in which landmark or background cues were removed or shifted revealed that pigeons’ search was controlled by both proximal landmarks and background cues, whereas humans relied only on the proximal landmarks. Pigeons’ search accuracy dropped substantially when they were presented with novel views of the same scene, whereas humans showed perfect transfer to novel views. In Experiment 2, pigeons with previous outdoor experience and humans were trained with 28 views of an outdoor scene. Both pigeons and humans transferred well to novel views of the scene. This positive transfer suggests that, under some conditions, pigeons, like humans, may encode the three-dimensional spatial information in images of a scene.     

Discipline‐related Marking Behaviour Using Percentages: a potential cause of inequity in assessment

This study set out to ascertain whether percentage mark distributions show evidence of discipline‐related marking behaviour and, if so, to consider the implications of this for equity in assessment outcomes. Performance data were obtained for 10 subjects at seven English universities for 1993–94, 1994–95 and 1995–96. The data showed that mark distributions at universities using percentages may be categorised into three Types (A,B and C). Type A distributions (English and History) are characterised by a steep‐sided negatively skewed distribution with a narrow spread. Pronounced microscale variation in the frequency is evident only in the vicinity of the mode between 55‐65%. Type B distributions (Biology, Business Studies, Fine Art, French, Law and Sociology) have a slightly broader spread and display microscale variation in frequency across a wider range of percentiles [40‐70%]. Type C distributions (Computer Studies and Mathematics) are characterised by a subdued, slightly negatively skewed distribution with a considerably wider spread. Type C distributions show conspicuous microscale variation in frequency across most of the percentile range. The types of distributions appear to reflect the relative confidence of assessors in different disciplines in awarding marks. The extremities of the percentage scale are perceived as insecure territory for the assessors of qualitative subject matter. Type A distributions are characteristic of disciplines in which the assessment is qualitative. Type B distributions may reflect the assessment of combined qualitative‐quantitative subject matter. Type C distributions are typical of disciplines in which more quantitative matter is assessed. The existence of discipline‐related patterns of distribution is a potential cause of inequity of outcomes for students on joint or multidisciplinary programmes. Data derived from institutions using grading scales show that discipline‐related patterns are less evident.     

The comparative efficacy of two approaches to teaching sixth graders opinion essay writing

Children in sixth grade randomly assigned to a teacher-made writing procedure anchored in the self-regulated strategy development (SRSD) model and training procedures were predicted to surpass children assigned to the comparison condition on dependent measures of writing clarity, organization, and cogency. The prediction was generally substantiated. The results suggest that the rate of change among individual children in the SRSD condition was faster than among children in the comparison condition on measures of clarity and organization. On the measure of cogency, findings showed that the rate of change among individuals in the SRSD condition compared to the comparison condition approached but did not reach statistical significance. Variance in growth parameters on the measure of writing clarity was statistically significant; however on the measure of organization, there was no substantive variation in individual growth parameters. Social validity data from all the children and teachers indicated the training was well received. The results are taken to support the efficacy of the SRSD model and training procedures.