There is a recent rekindled interest concerning the stability, reliability, and predictive validity of skilled performance across repeated measurements. One common phenomenon resulting from the repeated measures of subjects' performance across trials during skills acquisition is the superdiagonal correlation matrix, also known as the simplex matrix, in which correlations of performance decrease as a function of the separation of trials (or as a function of time). The present study collected fifty such correlation matrices from both published and unpublished sources. Next, the standardized item coefficient alphas were calculated from correlations for all possible combinations of adjacent trials to identify rules for which trials should be used to maximize reliability. When early or late adjacent trials showing low correlations were dropped from the computation of the standardized item coefficient alpha, reliability sometimes increased, although not dramatically. The rows of correlations above the diagonal of a superdiagonal matrix were plotted across trials and it was found that the resulting graphs could be used in deciding which adjacent early and/or late trials to drop to maximize the reliability. Seven figures, representative of the different sorts of published matrices, provide graphical decision rules for determining which trials to average to maximize reliability. The standardized coefficient alpha for the entire matrix should also be computed as a benchmark reliability / acase@tulane.edu

Langley (1990) found that a moderate level of caffeine-induced arousal elevated violence-primed men's interest in films involving aggression, but that higher levels did not. The current investigation tested three possible explanations for this inverted-U pattern of effects of arousal and priming upon attraction to media violence. Male participants primed with an aggressive story-writing task expressed more interest in seeing violent films (from a number of film selections described in brief paragraphs) than did men primed by writing nonaggressive stories, an effect enhanced by moderate caffeine dosage (2 or 4 milligrams per kilogram of body weight) but not by a greater dosage (6 mg/kg). Aggressively primed participants also considered violent films to be more violent, an effect linearly enhanced by increasing arousal by caffeine administration. Results indicate that priming and arousal each enhanced salience of violent content, which increased the men's interest in the material except among those most highly aroused who were more motivated to avoid material that could be additionally arousing / acase@tulane.edu

Identification of interaction effects is of increasing importance to the social sciences; however, interaction (or moderator) effects have often been difficult to detect with continuous data. Structural equation modeling (SEM) methods have been touted as a solution to the problem of detecting moderators with continuous data because they are thought to account for the presence of measurement error. Also some of the optional fitting algorithms are thought to be less sensitive to non-normality, a common characteristic of the cross-product terms used in evaluation of interaction effects. Although much of the literature to date describes SEM methods to detect interactions among latent variables, the current study contrasts well known moderated multiple regression (MMR) as compared to various analogous SEM models for estimating moderation among manifest variables. While some SEM estimation methods were found inferior, no clear advantage of any SEM method over MMR was observed in the detection of interaction effects. Furthermore, SEM models, with stable Type I error rates, either failed to converge or reported errors about 10% of the time while MMR always yielded a solution / acase@tulane.edu

Thesis (M.A.)--York University, 2001. / Includes abstract. "MQ-66385"--Fiche header. Includes bibliographical references (leaves 30-40).

This study investigated the relationship between synchronous neural activity and conscious visual perception by directly measuring neural synchrony in human EEG data collected during a perceptual task that controlled for the influence of attention. Improving a recently developed experimental paradigm and synchrony detection method (Rodriguez et al., 1999), participants viewed upright and scrambled Mooney face stimuli (fragmented black and white shapes that are perceived as faces upon visual closure) over 1000 ms exposures while performing a secondary attention task. During both presentation conditions, gamma-band synchrony increased to a maximum and then decreased to an above-baseline stationary level. Synchrony for the upright condition was significantly greater than synchrony for the scrambled condition during early and late portions of the exposure period. This result supports the hypothesis that neural synchrony mediates conscious visual organization and feature binding, although the possibility for a role in perception-related attention processes cannot be excluded.

<p> The low graduation rate of degree-seeking students at public community colleges is an important crisis facing communities across the United States. College satisfaction and withdrawal cognitions in students have been identified as key factors in college persistence by researchers. However, a review of the literature revealed no study in which a college-persistence intervention based on the personalization principle theory or using tailored messages has been conducted. The purpose of this study was to test the effectiveness of a college-persistence intervention, based on the personalization principle theory and Mashburn's theory, for students at a community college. This study used between-groups experimental research design and employed a nonprobability convenience sample comprising 108 college students at a regionally accredited public community college in the United States. Random assignment to 1 of 3 groups, including 2 experimental groups and 1 no-message control group, was conducted. The 2 experimental groups were the personalization-based tailored instructional messages and generalized instructional messages groups. A one-way MANOVA indicated that there was no significant difference in the college satisfaction and withdrawal cognitions of students in the experimental and control groups. A chi-square test of independence also indicated that there was no significant association between intervention type (personalization-based tailored instructional message, generalized instructional message, and no-message control) and college persistence. This study provides educators with a basis for social change with the debut of a prototype intervention that may be replicated and extended in future research to help students earn a college degree.</p>

The problems in the 2000 election in Florida focused national attention on the need for usable voting systems. As a result, the Help America Vote Act (HAVA) of 2002 provided funding for updating voting equipment and many states purchased direct recording electronic (DRE) systems. Although these electronic systems have been widely adopted, they have not been empirically proven to be more usable than their predecessors in terms of ballot completion times, error rates, or satisfaction levels for the average voter. The series of studies reported here provides usability data on DREs to compare with that of previous voting technologies (paper ballots, punch cards, and lever machines). Results indicate that there are not differences between DREs and older methods in efficiency or effectiveness. However, in terms of user satisfaction, the DREs are significantly better than the older methods. Paper ballots also perform well, but participants are much more satisfied with their experiences voting on the DREs. These studies also go beyond usability comparisons and test whether voters notice if their final ballots on the DRE reflect choices other than what the voters selected. Results indicate that over 60% of voters do not notice if their votes as shown on the review screen are different than how they were selected. Entire races can be added or removed from ballots and voter's candidate selections can be flipped and the majority of users do not notice. Beyond discovering that most voters do not detect the changes, these studies also identify several characteristics of the voter and the voting situation that are important in whether participants will or will not notice the changes. This means that attacks could be targeted to only those people who will most likely not notice the changes. The result is that malicious software installed on a DRE could steal votes right in front of voters with a low probability of being detected.

No description available.

Many current psycholinguistic theories view the mental lexicon as a listing of (only) unpredictable sound-meaning correspondences (primarily words and morphemes). Under this view, regular complex word forms and syntactic structures are built with rules during language production, obviating the need for storage of complex but regular linguistic material. This type of model conflicts with recent experimental evidence that suggests that lexical memory may in fact consist of a more heterogeneous set of linguistic units, including complex word forms and multi-word expressions that in theory could be constructed via rules. Storage of such material seems to be driven largely by frequency. The present research consisted of two experiments designed to investigate whether semantically transparent noun and adjective phrases are stored as single lexical units when they are very frequent. Results from the two tasks (grammaticality judgment and speech production) supported the notion that frequent word combinations can come to be stored holistically in lexical memory. It was argued that usage-based models of lexical memory (vs. dominant generative theories) best account for such data. Data from language acquisition, aphasia, and corpus studies were offered as complementary evidence in support of the more general claim that a large component of linguistic competence is knowledge of lexical co-occurrence patterns. Finally, it was hypothesized that an exemplar-based model of lexical memory best captures the range of available data.

A large number of behavioural methods have been developed to investigate nociception and the actions of analgesic drugs in animals. The formalin test is increasingly used as a model of injury-produced pain. The generally accepted method of rating pain used for mice is to count or time paw licks. The aim of this study was to examine scoring properties of other behaviours in the formalin test in mice, and determine the best measure of pain. / In the first experiment, the behavioural responses to intraplantar injection of a series of formalin concentrations were assessed. In the second experiment a fixed concentration of formalin was used, and the effects of increasing doses of various analgesic and non-analgesic drugs were examined. A time sampling method with momentary rating of nociceptive behaviours and behavioural state was used. / A correlational analysis of the data indicated that combinations of pain behaviours performed better than any single measurement, and the relationship between formalin concentration and behavioural measures were stronger when mice were habituated to the environment prior to testing. All four analgesic agents, morphine, amphetamine, dipyrone and xylazine, produced dose-dependent suppression of pain behaviours. The nociceptive measures were not significantly altered by sedative or neuroleptic drugs. / Considering the dose-effect relations for formalin and analgesic and non-analgesic agents, together, indicated that the sum of favouring, lifting and licking was the most consistent measure of both, pain and analgesia.