Sample size determinations for Welch's test in one‐way heteroscedastic ANOVA

For one‐way fixed effects ANOVA, it is well known that the conventional F test of the equality of means is not robust to unequal variances, and numerous methods have been proposed for dealing with heteroscedasticity. On the basis of extensive empirical evidence of Type I error control and power performance, Welch's procedure is frequently recommended as the major alternative to the ANOVA F test under variance heterogeneity. To enhance its practical usefulness, this paper considers an important aspect of Welch's method in determining the sample size necessary to achieve a given power. Simulation studies are conducted to compare two approximate power functions of Welch's test for their accuracy in sample size calculations over a wide variety of model configurations with heteroscedastic structures. The numerical investigations show that Levy's (1978a) approach is clearly more accurate than the formula of Luh and Guo (2011) for the range of model specifications considered here. Accordingly, computer programs are provided to implement the technique recommended by Levy for power calculation and sample size determination within the context of the one‐way heteroscedastic ANOVA model.     

Disagreement behind the veil of ignorance

In this paper we argue that there is a kind of moral disagreement that survives the Rawlsian veil of ignorance. While a veil of ignorance eliminates sources of disagreement stemming from self-interest, it does not do anything to eliminate deeper sources of disagreement. These disagreements not only persist, but transform their structure once behind the veil of ignorance. We consider formal frameworks for exploring these differences in structure between interested and disinterested disagreement, and argue that consensus models offer us a solution concept for disagreements behind the veil of ignorance.     

Rating Scales as Predictors—The Old Question of Scale Level and Some Answers

Rating scales as predictors in regression models are typically treated as metrically scaled variables or, alternatively, are coded in dummy variables. The first approach implies a scale level that is not justified, the latter approach results in a large number of parameters to be estimated. Therefore, when rating scales are dummy-coded, applications are often restricted to the use of a few predictors. The penalization approach advocated here takes the scale level serious by using only the ordering of categories but is shown to work in the high dimensional case. We consider the proper modeling of rating scales as predictors and selection procedures by using penalization methods that are tailored to ordinal predictors. In addition to the selection of predictors, the clustering of categories is investigated. Existing methodology is extended to the wider class of generalized linear models. Moreover, higher order differences that allow shrinkage towards a polynomial as well as monotonicity constraints and alternative penalties are introduced. The proposed penalization approaches are illustrated by use of the Motivational States Questionnaire.     

Development and Psychometric Evaluation of the Utrecht Grief Rumination Scale

Two different types of ruminative coping, depressive rumination and grief rumination, negatively influence bereavement outcome. Although grief-specific rumination is likely to be relevant in the bereavement context no internationally validated scale to measure grief rumination exists. Therefore, the current contribution aims to validate the Utrecht Grief Rumination Scale (UGRS), a scale developed to measure grief-specific rumination, in an English sample. Psychometric properties of the English UGRS were compared with those in a Dutch sample. 204 British adults (89 % women, 11 % men), bereaved on average 16 months ago, and 316 Dutch adults (88 % women, 12 % men), bereaved on average 12 months ago, filled out online questionnaires. Different types of rumination (grief rumination, brooding, reflection, trait rumination) and symptoms of psychopathology (anxiety, depression, complicated grief) were measured. A correlated five factor model provided the best fit for the UGRS. Multi-group comparisons showed that the factor structures of the English and Dutch version of the UGRS were highly similar across language groups. The UGRS showed excellent reliability. Results further supported the construct, convergent, divergent and concurrent validity of the English UGRS. The psychometric properties of the Dutch UGRS corroborated these findings. The UGRS appears a valid instrument to assess grief-specific rumination in international research and may have potential applicability as a clinical instrument to assess rumination in individuals with problematic grief.     

Building an Environmental Ethics from the Confucian Concepts of Zhengming and Datong

From the ‘DuPont factory’ case in China, one can see that contemporary ecology is faced with two underlying problems: A lack of responsibility toward the environment beyond being economically profitable, and a lack of care for what is outside of one’s immediate environment. For the purpose of confronting these two problems, I suggest two Confucian concepts: 1. zhengming 正名 (Rectification of names) and 2. datong 大同 (Great Harmony). These two concepts can be used to develop an environmental ethics and thus play a crucial role in solving the two above-mentioned problems. Zhengming is originally a political concept that was put forward by Confucius. According to this concept, everyone should fulfill their duty to the utmost in accordance with their individual roles. Datong is Confucius’ political ideal and emphasizes gong 公 (public) as a spirit for caring for tian xia 天下 (all under Heaven). A Confucian-style harmonious society is achieved by ‘letting every being manifest its mandate to the full’ (ge jin xing fen 各盡性分). When we turn toward the natural environment instead of political affairs, these concepts of zhengming and datong can become a proactive view of environmental ethics. From this view, zhengming emphasizes that ‘humans fulfill their responsibility of being humans’ (ren ren 人人). This means that humans should take responsibility toward the natural world, and one might say that ren ren implies an impetus for protecting the environment. Similarly, datong emphasizes caring for tian xia, by not limiting oneself to certain races, species, national boundaries, or geographical regions. Because of this, I believe that zhengming and datong can certainly resolve the above-mentioned problems: A lack of a sense of responsibility toward the environment, and a lack of a sense of care for what is outside of the confines of one’s immediate environment.     

Selectors' Decision Strategies when Assessing Immigrant Job Applicants

Immigrant job applicants are often not fluent in the majority language. This raises the question whether selectors adjust their decision strategy when selecting immigrants. In two field studies (N = 1,949 and N = 156), we examined the decision strategies of professional selectors. Selectors used differential strategies, giving less weight to the test scores and impression scores of immigrants. Dutch language proficiency served as a moderator variable; test scores were considered less important in the employment recommendation especially for immigrants with low language skills. Yet professional selectors also used similar strategies for different groups; the same test scores led to the same recommendations, regardless of ethnicity. In sum, personnel selectors adjusted their decision strategy for immigrants, but this did not lead to immigrants receiving higher recommendations than majority applicants with similar test scores.     

The effect of reward on orienting and reorienting in exogenous cuing

It is thought that reward-induced motivation influences perceptual, attentional, and cognitive control processes to facilitate behavioral performance. In this study, we investigated the effect of reward-induced motivation on exogenous attention orienting and inhibition of return (IOR). Attention was captured by peripheral onset cues that were nonpredictive for the target location. Participants performed a target discrimination task at short (170 ms) and long (960 ms) cue–target stimulus onset asynchronies. Reward-induced motivation was manipulated by exposing participants to low- and high-reward blocks. Typical cue facilitation effects on initial orienting were observed for both the low- and high-reward conditions. However, IOR was found only for the high-reward condition. This indicates that reward-induced motivation has a clear effect on reorienting and inhibitory processes following the initial capture of attention, but not on initial exogenous orienting that is considered to be exclusively automatic and stimulus-driven. We suggest that initial orienting is completely data-driven, not affected by top-down motivational processes, while reorienting and the accompanying IOR effect involve motivational top-down processes. To support this, we showed that reward-induced motivational processes and top-down control processes co-act in order to improve behavioral performance: High-reward-induced motivation caused an increase in top-down cognitive control, as signified by posterror slowing. Moreover, we show that personality trait propensity to reward-driven behavior (BAS-Drive scale) was related to reward-triggered behavioral changes in top-down reorienting, but not to changes in automatic orienting.     

Der Fall Ludwig Tessnow (1872–1939)

The journeyman carpenter Ludwig Tessnow was sentenced to death for four murders by the Greifswald jury court in 1902. The death sentence was upheld during the retrial in 1906 but was later commuted to life imprisonment. According to the unanimous opinion of psychiatric experts Tessnow committed the crimes while in a state of mental incompetence caused by epileptic twilight states. The court, however, ignored this mitigating circumstance in its decision-making process. Seen from a historical perspective, the case is of forensic psychiatric interest because this criminal trial clearly shows the conflicts in competence which arose in the nineteenth century between judges and medical experts when mental competence had to be assessed. It also allows some insight into how mentally ill offenders were dealt with at the beginning of the twentieth century when the influence of public opinion was (and still is) a noteworthy element of prejudgement which was additionally consolidated by the established system of jury courts. The Tessnow case reveals by way of example the usual practice of official consignment of mentally disordered offenders to hospitals at the end of the nineteenth century until the Nazi era. New particulars of the Tessnow findings adequately verified that Tessnow had not been executed in the Greifswald prison as mistakenly believed. It could be proved that Ludwig Tessnow was admitted to the LandesheilanstaltStralsund (state mental hospital in Stralsund) where he became a victim of the Nazi euthanasia program.     

Research-Based Knowledge in Psychology: What,if Anything,is Its Incremental Value to the Practitioner?

This essay reflects an ongoing dialogue between a clinician versed in mainstream psychological research and theory, and a social psychologist with experience both as a researcher and contributor to applied undertakings in various domains about the “incremental value” of research-based knowledge—that is, its value beyond that provided by the other sources of knowledge available to the practitioner. These sources include knowledge about the needs and coping strategies of all human beings, as well as knowledge both about the specific life circumstances of those one is seeking to help, and knowledge about language and culture. Examples from the clinical practice of the first author are offered, coupled with in-principle arguments about the underspecified and contingent nature of research-based generalizations. By way of rebuttal, examples of arguably useful findings are provided by the second author—especially findings that serve as correctives to biases in lay psychology (notably unwarranted “dispositionism”) and to widespread shortcomings in judgment and decision-making (particularly, Kahneman and Tversky’s work on “prospect theory” ). Both authors agree on the value of a “bricoleur” treatment strategy that relies on careful attention to the specifics of the case at hand and avoids one-size-fits-all applications of theory and prior research, and both agree that research-based findings are more useful in predicting behavior and designing intervention strategies that apply to groups and large samples of individuals rather than single actors. A concluding discussion focuses on necessary criteria and strategies for increasing the usefulness of laboratory and field research for the practitioner.