Improving the performance of knowledge and information systems

Dick Kuiper, a rural sociologist, is a research associate with the Department of Extension Science, Wageningen, Agricultural University, Hollandseweg, 6706 KN Wageningen, The Netherlands. He is involved in research on agricultural knowledge and information systems.     

Depression and causal attributions for success and failure

The present study investigated the effects of depression on causal attributions for success and failure. Specifically, female university students were separated into depressed and nondepressed groups on the basis of Costello--Comrey Depression Scale scores, and then received either 20%, 55%, or 80% reinforcement on a word association task. Following the task, attributions were made for outcome using the four factors of effort, ability, task difficulty, and luck. In accord with predictions generated from a self-serving biases hypothesis, nondepressives made internal (ability, effort) attributions for a successful outcome (80% reinforcement) and external attributions (luck, task difficulty) for a failure outcome (20% reinforcement). As predicted from consideration of the self-blame component of depression, the attributions made by depressives for a failure outcome were personal or internal. Contrary to expectations, depressives also made internal attributions for a successful outcome. The findings for depressives were discussed in relation to the recently revised learned helplessness model of depression, which incorporates causal attributions. For nondepressives, the findings were considered in terms of the self-serving biases hypothesis.     

Phenomenal characteristics associated with real and imagined events: the effects of event valence and absorption

This study examined the effects of emotional valence of an event and individual differences in absorption on the phenomenal characteristics associated with real and imagined events. Each participant described four events. Two of these were real and two were imagined, with one pleasant and stressful event being generated for each category. Pleasant events (both real and imagined) contained more detail (visual detail, smell, and taste, and more information regarding location, time, etc.) than stressful events. In addition, higher levels of absorption were related to higher ratings for both real and imagined events (for both pleasant and stressful events). Discussion focused on implications for further research in source monitoring and other relevant domains. Copyright © 1999 John Wiley & Sons, Ltd.     

The effects of depression and cognitive vulnerability to depression on judgments of similarity between self and other

The present research was conducted to investigate the effects of mild levels of depression, and cognitive vulnerability to depression, on people's perceptions of their similarity to others. Depression level was assessed using the Beck Depression Inventory, and cognitive vulnerability was measured with the Dysfunctional Attitude Scale. Subjects rated their similarity to others on a 7-point scale and also generated a list of attributes thought to typify the average other person. In terms of similarity judgments, individuals perceived themselves to be less similar to others as depression level increased. Furthermore, and also as predicted, only individuals scoring high on the vulnerability measure exhibited this pattern. Given the consistently positive view of others expressed by all subjects, this latter finding suggests that vulnerable individuals saw themselves as increasingly distinctive with respect to their own negative attributes, as depression level increased. This social comparison interpretation is consistent with previous research indicating that vulnerable individuals change from a focus on self-referent positive traits when nondepressed to a focus on negative traits when depressed. This pattern is also identified as a possible contributor to the social isolation and interpersonal difficulties characteristic of depression.     

Vulnerability to depression,mild depression,and degree of self-schema consolidation

The present study investigated the degree of consolidation of self-schema content in mildly depressed individuals, individuals cognitively vulnerable to depression (but currently nondepressed), and nonvulnerable-nondepressed controls. All three groups of subjects were presented with pairs of adjectives involving one depressed and one nondepressed content adjective, and were asked to decide which of the two adjectives described them the best (or least). Following this, subjects rated each adjective on a 9-point degree of self-reference scale. On the basis of these two types of self-referent judgments, a measure of decision inconsistency was computed for each subject. In accord with predictions generated from a self-schema model of depression, similar decision inconsistency scores were found for mildly depressed and vulnerable-nondepressed individuals. In turn, both of these groups revealed greater decision inconsistencies than normal controls (the nonvulnerable-nondepressed group). Using the inconsistency measure as an index of the degree of consolidation of self-schema content, these findings suggest that relatively poor consolidation of depressed and nondepressed self-schema content may relate to both the etiology and maintenance of depression.     

Symbolic distance and congruity effects for paired-comparisons judgments of degree of self-reference

Two experiments are reported which speak to the properties of the process of self-reference. The first demonstrated a “symbolic distance effect” for self-reference. An inverse linear relation was found between item difference on a self-referent continuum and the time required to judge which of a pair of adjectives best described the respondent. The second experiment failed to demonstrate a “congruity effect” in a situation where subjects decided which of a pair of adjectives BEST or LEAST described them. This failure was interpreted as support for the proposition that the self functions as an immovable, rigid, and fixed reference point during the processing of personal information. Discussion focused upon how this fixed reference point property helps understand some other research findings.     

Effectiveness of an attachment-based intervention for the assessment of parenting capacities in maltreating families: A randomized controlled trial

Even though Parenting Capacity Assessments (PCAs) are essential for child protection services to support placement decisions for maltreating families, presently no evidence-based PCA protocols are available. In this randomized controlled trial, we tested the quality of an attachment-based PCA protocol based on Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD). We recruited 56 parent-child dyads (M_age children = 3.48 years) in Dutch family residential clinics that conduct PCAs to support placement decisions. After pretest, families were randomized to receive the Regular Assessment Procedure (RAP) (n = 28), or an additional assessment based on VIPP-SD (n = 28). An immediate post-test and a 10-month follow-up were conducted. Multilevel models showed that therapists felt equally confident about their recommendations regarding child placement for both groups and that they equally often modified their initial placement recommendations. Moreover, children in the VIPP-SD group did not show fewer behavior problems and did not experience recurring child maltreatment less often than children in the RAP group. Thus, we found no evidence that PCAs incorporating the VIPP-SD protocol outperformed PCAs as usual. We discuss possible explanations why in the current study VIPP-SD did not seem to add to the quality of the RAP.     

Properties of hypothesis testing techniques and (Bayesian) model selection for exploration‐based and theory‐based (order‐restricted) hypotheses

In this paper, the performance of six types of techniques for comparisons of means is examined. These six emerge from the distinction between the method employed (hypothesis testing, model selection using information criteria, or Bayesian model selection) and the set of hypotheses that is investigated (a classical, exploration‐based set of hypotheses containing equality constraints on the means, or a theory‐based limited set of hypotheses with equality and/or order restrictions). A simulation study is conducted to examine the performance of these techniques. We demonstrate that, if one has specific, a priori specified hypotheses, confirmation (i.e., investigating theory‐based hypotheses) has advantages over exploration (i.e., examining all possible equality‐constrained hypotheses). Furthermore, examining reasonable order‐restricted hypotheses has more power to detect the true effect/non‐null hypothesis than evaluating only equality restrictions. Additionally, when investigating more than one theory‐based hypothesis, model selection is preferred over hypothesis testing. Because of the first two results, we further examine the techniques that are able to evaluate order restrictions in a confirmatory fashion by examining their performance when the homogeneity of variance assumption is violated. Results show that the techniques are robust to heterogeneity when the sample sizes are equal. When the sample sizes are unequal, the performance is affected by heterogeneity. The size and direction of the deviations from the baseline, where there is no heterogeneity, depend on the effect size (of the means) and on the trend in the group variances with respect to the ordering of the group sizes. Importantly, the deviations are less pronounced when the group variances and sizes exhibit the same trend (e.g., are both increasing with group number).