Prosperity Beliefs and Value Orientations: Fueling or Suppressing Entrepreneurial Activity

Entrepreneurs tend to think differently than nonentrepreneurs. Among the differences are values prizing achievement and self‐direction, while downplaying tradition and conformity. Religion is an important correlate to human values. Nevertheless, previous research has failed to explore adequately the connections among religious beliefs, human values, and entrepreneurial outcomes. The purpose of this study is to test these relationships with a focus on beliefs that God rewards the faithful with material prosperity. We test eight hypotheses using a national survey of working adults. Results of a multigroup path model reveal that value orientations of self‐enhancement, openness to change, and conservation are associated with entrepreneurial attitudes of opportunity recognition and risk willingness. These attitudes likewise correlate with new business creation. Prosperity beliefs moderate the impact of values and entrepreneurial attitudes on the likelihood of starting a new business, but prosperity beliefs by themselves show little direct impact on entrepreneurial attitudes or action.     

Learning by Collaborative and Individual‐Based Recommendation Agents

Intelligent recommendation systems can be based on 2 basic principles: collaborative filters and individual‐based agents. In this work we examine the learning function that results from these 2 general types of learning‐smart agents. There has been significant work on the predictive properties of each type, but no work has examined the patterns in their learning from feedback over repeated trials. Using simulations, we create clusters of “consumers” with heterogeneous utility functions and errorful reservation utility thresholds. The consumers go shopping with one of the designated smart agents, receive recommendations from the agents, and purchase products they like and reject ones they do not. Based on the purchase–no purchase behavior of the consumers, agents learn about the consumers and potentially improve the quality of their recommendations. We characterize learning curves by modified exponential functions with an intercept for percentage of recommendations accepted at Trial 0, an asymptotic rate of recommendation acceptance, and a rate at which learning moves from intercept to asymptote. We compare the learning of a baseline random recommendation agent, an individual‐based logistic‐regression agent, and two types of collaborative filters that rely on K‐mean clustering (popular in most commercial applications) and nearest‐neighbor algorithms. Compared to the collaborative filtering agents, the individual agent (a) learns more slowly, initially, but performs better in the long run when the environment is stable; (b) is less negatively affected by permanent changes in the consumer's utility function; and (c) is less adversely affected by error in the reservation threshold to which consumers compare a recommended product's utility. The K‐mean agent reaches a lower asymptote but approaches it faster, reflecting a surprising stickiness of target classifications after feedback from recommendations made under initial (incorrect) hypotheses.     

Spatial learning in the rat: impairment induced by the thiol-proteinase inhibitor, leupeptin, and an analysis of [3H]glutamate receptor binding in relation to learning

Rats were given continuous intraventricular infusion of saline or the thiol-proteinase inhibitor leupeptin, via subcutaneously implanted osmotic minipumps, while being trained on a spatial learning water task using spaced trials. Leupeptin caused overnight forgetting during training, but performance eventually reached asymptote in both groups. A retention test conducted 48 h later to assess spatial memory revealed no significant group differences, but did cause, in saline-treated rats only, a disruption of subsequent retraining back to the correct spatial location. The groups showed no differences in Cl-dependent [3H]glutamate receptor binding to hippocampal or entorhinal cortex membranes subsequent to training. In a second experiment, normal rats trained on the same task also showed no differences in Cl-dependent [3H]glutamate binding relative to rats exposed to the water task but given random spatial position training and handled controls. The results are discussed in relation to the hypothesis of Lynch and Baudry (Science (1984) 224, 1057-1063) that a calcium-dependent thiol proteinase is involved in memory formation through its ability to modify glutamate receptor distribution and dendritic spine shape.     

A case of thalamic aphasia with postmortem verification

This study discusses a case of aphasia after dominant thalamic lesion, a hemorrhagic infarction. Unlike other such cases, both repeated standardized assessment and postmortem verification were available. The patient was assessed at 3 weeks and again at 9 weeks postonset. The aphasia demonstrated the syndrome common to dominant thalamic hemorrhage: fluent but paraphasic output sometimes deteriorating to jargon, comprehension less impaired than this type of output usually indicates, and the least impairment in repetition. As sometimes reported in previous cases, semantic paraphasias were more common than phonemic paraphasias. The lesion was located in the dorsal aspect of the lateral nucleus, but it extended into the pulvinar, including the anterior superior lateral aspect which has been implicated in language by previous studies. Thus, data from this case are consistent with an involvement of the dominant pulvinar in language and suggest that this role involves the semantic aspects of language.     

Pluralistic ignorance and college student perceptions of gender-specific alcohol norms.

Students' perceived norms and personal concern about alcohol use were examined in 4 (N=971) experiments. Men reported that same-sex peers were less concerned about campus alcohol practices than themselves or female students; women believed that they were more concerned about campus alcohol practices than both same- and opposite-sex peers (Experiments 1 and 2). Additional evidence suggested that students were not merely engaging in impression management. Men reported more social pressure to drink and greater embarrassment about expressing drinking-related concerns; women expected more severe consequences if they drank excessively (Experiment 3). A male student (vs female student) expressing concerns about alcohol was believed to experience greater difficulties fitting in (Experiment 4). Implications for peer influence and drug use intervention are discussed.