Daniel Hausmann

Bio: Daniel Hausmann is an academic researcher from University of Zurich. The author has contributed to research in topics: Ambiguity aversion & Heuristics. The author has an hindex of 7, co-authored 13 publications receiving 378 citations. Previous affiliations of Daniel Hausmann include Information Technology University.

Unpacking the exploration–exploitation tradeoff: A synthesis of human and animal literatures.

Abstract: Many decisions in the lives of animals and humans require a fine balance between the exploration of different options and the exploitation of their rewards. Do you buy the advertised car, or do you test drive different models? Do you continue feeding from the current patch of flowers, or do you fly off to another one? Do you marry your current partner, or try your luck with someone else? The balance required in these situations is commonly referred to as the exploration– exploitation tradeoff. It features prominently in a wide range of research traditions, including learning, foraging, and decision making literatures. Here, we integrate findings from these and other often-isolated literatures in order to gain a better understand- ing of the possible tradeoffs between exploration and exploitation, and we propose new theoretical insights that might guide future research. Specifically, we explore how potential tradeoffs depend on (a) the conceptualization of exploration and exploitation; (b) the influencing environmental, social, and individual factors; (c) the scale at which exploration and exploitation are considered; (d) the relationship and types of transitions between the 2 behaviors; and (e) the goals of the decision maker. We conclude that exploration and exploitation are best conceptualized as points on a continuum, and that the extent to which an agent’s behavior can be interpreted as exploratory or exploitative depends upon the level of abstraction at which it is considered.

Incautious Reasoning as a Pathogenetic Factor for the Development of Psychotic Symptoms in Schizophrenia

Abstract: Previous studies indicate that schizophrenia patients draw decisions more hastily than controls. The aim of the present study was to obtain convergent evidence with a new paradigm, designed after the Who Wants to Be a Millionaire television game show. Thirty-two schizophrenia patients and 38 healthy subjects were administered 20 knowledge questions, along with 4 response alternatives. Participants were required to provide probability estimates for each alternative. Whenever a subject was confident that one of the alternatives was correct or was wrong, the subject was asked to indicate this via a decision or rejection rating. Thus, probability estimates and decisions were independently assessed, allowing determination of the point at which probability estimates translate into decisions. Patients and controls gave comparable probability estimates for all alternatives. However, patients committed more erroneous responses, owing to their making decisions in the face of low subjective probability ratings and rejecting alternatives despite rather high probability ratings. The results provide further evidence for the claim that schizophrenia patients make strong judgments based on little information. We propose that a lowered threshold for accepting alternatives provides a parsimonious explanation for the data-gathering bias reported in the literature.

Sequential evidence accumulation in decision making: The individual desired level of confidence can explain the extent of information acquisition

Abstract: Judgments and decisions under uncertainty are frequently linked to a prior sequential search for relevant information. In such cases, the subject has to decide when to stop the search for information. Evidence accumulation models from social and cognitive psychology assume an active and sequential information search until enough evidence has been accumulated to pass a decision threshold. In line with such theories, we conceptualize the evidence threshold as the “desired level of confidence” (DLC) of a person. This model is tested against a fixed stopping rule (one-reason decision making) and against the class of multi-attribute information integrating models. A series of experiments using an information board for horse race betting demonstrates an advantage of the proposed model by measuring the individual DLC of each subject and confirming its correctness in two separate stages. In addition to a better understanding of the stopping rule (within the narrow framework of simple heuristics), the results indicate that individual aspiration levels might be a relevant factor when modelling decision making by task analysis of statistical environments.

Methods for inducing intuitive and deliberate processing modes

Abstract: Over the past years, an increasing number of studies directly comparing intuition and deliberation were published. One of the most obvious ways to learn about differences between intuitive and deliberate processes is to induce the increased application of one or the other processing mode and to measure behavioural differences. An in-depth analysis of the literature reveals that different methods to manipulate intuitive and deliberate judgment and decision making are available. For instance, participants can be instructed to decide “intuitively” or “deliberately” and their choices can be analysed.

Tracing the decision-making process of physicians with a Decision Process Matrix

Abstract: Decision-making processes in a medical setting are complex, dynamic and under time pressure, often with serious consequences for a patient’s condition. The principal aim of the present study was to trace and map the individual diagnostic process of real medical cases using a Decision Process Matrix [DPM]). The naturalistic decision-making process of 11 residents and a total of 55 medical cases were recorded in an emergency department, and a DPM was drawn up according to a semi-structured technique following four steps: 1) observing and recording relevant information throughout the entire diagnostic process, 2) assessing options in terms of suspected diagnoses, 3) drawing up an initial version of the DPM, and 4) verifying the DPM, while adding the confidence ratings. The DPM comprised an average of 3.2 suspected diagnoses and 7.9 information units (cues). The following three-phase pattern could be observed: option generation, option verification, and final diagnosis determination. Residents strove for the highest possible level of confidence before making the final diagnoses (in two-thirds of the medical cases with a rating of practically certain) or excluding suspected diagnoses (with practically impossible in half of the cases). The following challenges have to be addressed in the future: real-time capturing of emerging suspected diagnoses in the memory of the physician, definition of meaningful information units, and a more contemporary measurement of confidence. DPM is a useful tool for tracing real and individual diagnostic processes. The methodological approach with DPM allows further investigations into the underlying cognitive diagnostic processes on a theoretical level and improvement of individual clinical reasoning skills in practice.

Hopping, skipping or jumping to conclusions? Clarifying the role of the JTC bias in delusions

Abstract: Introduction: There is substantial evidence that patients with delusions exhibit a reasoning bias - known as the "jumping to conclusions" (JTC) bias - which leads them to accept hypotheses as correct on the basis of less evidence than controls. We address three questions concerning the JTC bias that require clarification. Firstly, what is the best measure of the JTC bias? Second, is the JTC bias correlated specifically with delusions, or only with the symptomatology of schizophrenia? And third, is the bias enhanced by emotionally salient material? Methods To address these questions, we conducted a series of meta-analyses of studies that used the Beads task to compare the probabilistic reasoning styles of individuals with and without delusions. Results We found that only one of four measures of the JTC bias - "draws to decision" -reached significance. The JTC bias exhibited by delusional subjects - as measured by draws to decision - did not appear to be solely an epiphenomenal effect of schizophrenic symptomatology, and was not amplified by emotionally salient material. Conclusions A tendency to gather less evidence in the Beads task is reliably associated with the presence of delusional symptomatology. In contrast, certainty on the task, and responses to contradictory evidence, do not discriminate well between those with and without delusions. The implications for the underlying basis of the JTC bias, and its role in the formation and maintenance of delusions, are discussed.

Psychosis, Delusions and the “Jumping to Conclusions” Reasoning Bias: A Systematic Review and Meta-analysis

Abstract: We did a systematic review and meta-analysis to investigate the magnitude and specificity of the "jumping to conclusions" (JTC) bias in psychosis and delusions. We examined the extent to which people with psychosis, and people with delusions specifically, required less information before making decisions. We examined (1) the average amount of information required to make a decision and (2) numbers who demonstrated an extreme JTC bias, as assessed by the "beads task." We compared people with psychosis to people with and without nonpsychotic mental health problems, and people with psychosis with and without delusions. We examined whether reduced data-gathering was associated with increased delusion severity. We identified 55 relevant studies, and acquired previously unpublished data from 16 authors. People with psychosis required significantly less information to make decisions than healthy individuals (k= 33,N= 1935,g= -0.53, 95% CI -0.69, -0.36) and those with nonpsychotic mental health problems (k= 13,N= 667,g= -0.58, 95% CI -0.80, -0.35). The odds of extreme responding in psychosis were between 4 and 6 times higher than the odds of extreme responding by healthy participants and participants with nonpsychotic mental health problems. The JTC bias was linked to a greater probability of delusion occurrence in psychosis (k= 14,N= 770, OR 1.52, 95% CI 1.12, 2.05). There was a trend-level inverse association between data-gathering and delusion severity (k= 18;N= 794;r= -.09, 95% CI -0.21, 0.03). Hence, nonaffective psychosis is characterized by a hasty decision-making style, which is linked to an increased probability of delusions.

Unpacking the exploration–exploitation tradeoff: A synthesis of human and animal literatures.

Abstract: Many decisions in the lives of animals and humans require a fine balance between the exploration of different options and the exploitation of their rewards. Do you buy the advertised car, or do you test drive different models? Do you continue feeding from the current patch of flowers, or do you fly off to another one? Do you marry your current partner, or try your luck with someone else? The balance required in these situations is commonly referred to as the exploration– exploitation tradeoff. It features prominently in a wide range of research traditions, including learning, foraging, and decision making literatures. Here, we integrate findings from these and other often-isolated literatures in order to gain a better understand- ing of the possible tradeoffs between exploration and exploitation, and we propose new theoretical insights that might guide future research. Specifically, we explore how potential tradeoffs depend on (a) the conceptualization of exploration and exploitation; (b) the influencing environmental, social, and individual factors; (c) the scale at which exploration and exploitation are considered; (d) the relationship and types of transitions between the 2 behaviors; and (e) the goals of the decision maker. We conclude that exploration and exploitation are best conceptualized as points on a continuum, and that the extent to which an agent’s behavior can be interpreted as exploratory or exploitative depends upon the level of abstraction at which it is considered.