Children can solve Bayesian problems: the role of representation in mental computation

Can children reason the Bayesian way? We argue that the answer to this question depends on how numbers are represented, because a representation can do part of the computation. We test, for the first time, whether Bayesian reasoning can be elicited in children by means of natural frequencies. We show that when information was presented to fourth, fifth, and sixth graders in terms of probabilities, their ability to estimate the Bayesian posterior probability was zero. Yet when the same information was presented in natural frequencies, Bayesian reasoning showed a steady increase from fourth to sixth grade, reaching an average level of 19, 39, and 53%, respectively, in two studies. Sixth graders' performance with natural frequencies matched the performance of adults with probabilities. But this general increase was accompanied by striking individual differences. More than half of the sixth graders solved most or all problems, whereas one third could not solve a single one. An analysis of the children's responses provides evidence for the use of three non-Bayesian strategies. These follow an overlapping wave model of development and continue to be observed in the minds of adults. More so than adults' probabilistic reasoning, children's reasoning depends on a proper representation of information.     

Representation facilitates reasoning: what natural frequencies are and what they are not

A good representation can be crucial for finding the solution to a problem. Gigerenzer and Hoffrage (Psychol. Rev. 102 (1995) 684; Psychol. Rev. 106 (1999) 425) have shown that representations in terms of natural frequencies, rather than conditional probabilities, facilitate the computation of a cause's probability (or frequency) given an effect--a problem that is usually referred to as Bayesian reasoning. They also have shown that normalized frequencies--which are not natural frequencies--do not lead to computational facilitation, and consequently, do not enhance people's performance. Here, we correct two misconceptions propagated in recent work (Cognition 77 (2000) 197; Cognition 78 (2001) 247; Psychol. Rev. 106 (1999) 62; Organ. Behav. Hum. Decision Process. 82 (2000) 217): normalized frequencies have been mistaken for natural frequencies and, as a consequence, "nested sets" and the "subset principle" have been proposed as new explanations. These new terms, however, are nothing more than vague labels for the basic properties of natural frequencies.     

Menschenbild und Psychotherapie

Images of humans provide preliminary answers to the question of what essentially constitutes their situation. In psychoanalytically based procedures images have appeared from time immemorial, which especially emphasize the animal impulses, the emotions, the interpersonal situation and in contrast, the self-reflecting subject, the capabilities for speech, communication and culture. In addition to this, in this discussion special attention is paid to the changing economic and technological circumstances, which displace humans into a novel living environment and could possibly bring about new forms of personality development with respect to the biological nature and also the sociocultural possibilities. As a consequence for psychotherapy, the consideration of these anthropological aspects is recommended beyond the processing of individual mental disorders.     

Managing a stigmatized identity—evidence from a longitudinal analysis about people with mental illness

Previous research about coping with the stigma of mental illness mostly relied on cross‐sectional or qualitative research designs. In the present study, the consequences of ten identity management strategies for mental illness stigma were observed in a longitudinal design. Cross‐lagged analyses were used to describe the influence of the strategies on the frequency of stigma experiences and on mental health in a two‐wave panel of people with mental illness (n = 367, 79% repeated response rate). Selective disclosure and information seeking emerged as adaptive identity management strategies, whereas overcompensation and withdrawal led to lower mental health. Results were mostly unaffected by demographic and psychiatric variables. The results support an empowerment model of stigma resilience that portrays stigmatized people as active constructors of their social world.     

The Janus face in group psychotherapy

Combined therapy offers the practitioner a rich data field for observation and research. Seeing the same patient in the group and in individual analytic therapy raises certain questions such as how differently does the patient present him- or herself, what does the difference or lack of difference mean, and is it prognostically meaningful. Based on ego theory, the author hypothesized that different therapeutic environments ought to evoke different levels of response. This adaptive quality was thought to be prognostically significant and indicative of a greater possibility for structural change. A small clinical sample showed a tendency in that direction.