Testing the reinforcing properties of S-: a replication of Lieberman''s procedure

A critical issue in testing theories of observing is whether the stimulus associated with extinction (the S-) reinforces observing responses. In previous experiments, subjects have been trained to make observing responses that produce both the S- and the stimulus correlated with reinforcement (the S+). Then, either the S+ or the S- has been withheld. Conflicting results have been attributed to differences among species. In the present experiments, pecking one key by master pigeons was reinforced with grain on a variable-ratio extinction schedule. Yoked pigeons received the grain on a variable-interval, extinction schedule controlled by the variable-ratio performances of the master birds. For both groups, concurrent pecking on a second key was reinforced on a variable-interval schedule with displays of discriminative stimuli. Subsequently, either the S+ or the S- was eliminated from the procedure. Omission of S+ produced a large decrease, as predicted by traditional conditioned reinforcement accounts of observing. By itself, S- did not maintain observing. A smaller and less reliable decrease, comparable to that obtained by Lieberman (1972) with rhesus monkeys, occurred when S- was eliminated. This replication with pigeons of Lieberman's results indicates that they are not species-specific, and the fact that observing was not maintained by S- alone suggests that the decrease obtained when S- was omitted is not attributable to the reinforcing power of S-.     

Human observing: Maintained by stimuli correlated with reinforcement but not extinction

College students received points exchangeable for money (reinforcement) on a variable-time 60-second schedule that alternated randomly with an extinction component. Subjects were informed that responding would not influence either the rate or distribution of reinforcement. Instead, presses on either of two levers (“observing responses”) produced stimuli. In each of four experiments, stimuli positively correlated with reinforcement and/or stimuli uncorrelated with reinforcement were each chosen over stimuli correlated with extinction. These results are consistent with prior results from pigeons in supporting the conditioned-reinforcement hypothesis of observing and in not supporting the uncertainty-reduction hypothesis.     

项目难度与被试能力分布最优匹配的模拟研究

该文运用蒙特卡罗方法对被测试能力分布与测验项目难度分布的匹配问题进行模拟分析,分析表明当能力分布为正态分布正偏态分布和负偏态分布时分别与测验项目难度分布与为正态分布,正偏态分布和负偏态分布匹配,比别的匹配有更高测验期望信息值,测验最大信息测验 系数,并且测验信息曲线最大值的能力点与能力分布的众数愈相一致,测验项目参数估计值性真实值的相关也更高。     

信息加工认知心理学的发展和面临的挑战

本文认为当代信息加工认知心理学发展的特点是：（１）与高新科学技术结合．在基础理论的研究方面有较大的突破;（２）将自然认知与社会认知的研究结合起来,促使信息加工的研究能更接近人类实际的认知过程：（３）将基础理论研究与应用研究相结合,不断扩大认知心理学的研究领域和应用范围．为了迎接面临的挑战和适应社会发展的需要,信息加工认知心理学应更充分地体现时代精神,坚持走实验研究和现象学研究相结合、定量研究与定性研究相结合、微观研究与宏观研究相结合,以及文理互补、多科渗透的发展道路。     

迎接21世纪生命科学的新时代：———基因组与蛋白组计划时代

当全世界人类基因组计划在近年取得迅速和突出的进展,即将来临床的２１世纪将带领人类基因组计,划进入一个基基因组时代、蛋白组计划、生物信息学的新时代,所有这些将构成２１世纪生命科学研究的核心前沿和主流。同亲,生物信息学的成果将高度地拓展生命科学新的研究领域和加速其研究的里程。多种多样数以千万计的生命模式（如生物大分子结构功能的模式）的数字化,将是加快生命科学信息化步入一个崭新的水平和时代的必由之路。     

The morality of scientific openness

The ideal of scientific openness — i.e. the idea that scientific information should be freely accessible to interested parties — is strongly supported throughout the scientific community. At the same time, however, this ideal does not appear to be absolute in the everyday practice of science. In order to get the credit for new scientific advances, scientists often keep information to themselves. Also, it is common practice to withhold information obtained in commissioned research when the scientist has agreed with his or her employer to do so. The secrecy may be intended for ever, as in the military area, but also temporarily until a patent application has been made. The paper explores to what extent such secrecy is undesirable, as seems to be suggested by the ideal of scientific openness. Should this ideal be interpreted as having certain exceptions which make the above-mentioned practices acceptable? Are there, on closer inspection, good arguments for the ideal of scientific openness, and for officially upholding it? Possible versions of the ideal of scientific openness are explored and the issue is found to be rather complex, allowing for wide variations depending on the acting parties, beneficiaries, types of information and moral requirements involved. We conclude that the arguments usually given in favour of this ideal are weaker than what seems to be generally believed, and that, on closer inspection, they leave plenty of room for exceptions to it. These exceptions only partly cover the actual practice of withholding scientific information, and there may still be good reason to advocate, teach and enforce the ideal of scientific openness within the scientific community.     

A study of algorithms for covariance structure analysis with specific comparisons using factor analysis

Several algorithms for covariance structure analysis are considered in addition to the Fletcher-Powell algorithm. These include the Gauss-Newton, Newton-Raphson, Fisher Scoring, and Fletcher-Reeves algorithms. Two methods of estimation are considered, maximum likelihood and weighted least squares. It is shown that the Gauss-Newton algorithm which in standard form produces weighted least squares estimates can, in iteratively reweighted form, produce maximum likelihood estimates as well. Previously unavailable standard error estimates to be used in conjunction with the Fletcher-Reeves algorithm are derived. Finally all the algorithms are applied to a number of maximum likelihood and weighted least squares factor analysis problems to compare the estimates and the standard errors produced. The algorithms appear to give satisfactory estimates but there are serious discrepancies in the standard errors. Because it is robust to poor starting values, converges rapidly and conveniently produces consistent standard errors for both maximum likelihood and weighted least squares problems, the Gauss-Newton algorithm represents an attractive alternative for at least some covariance structure analyses.Work by the first author has been supported in part by Grant No. Da01070 from the U. S. Public Health Service. Work by the second author has been supported in part by Grant No. MCS 77-02121 from the National Science Foundation.     

Psychoanalysts in the Public Eye: Internal Resistances

An attitude against public presentations has been part of the inward looking stance of organized psychoanalysis and has contributed to the often-heard comment that psychoanalysis is a dying profession. Because of the very private nature of clinical psychoanalytic work, this ambivalence to public appearances continues to exist in all psychoanalysts. We have to realize that it is crucial for psychoanalysts to educate the public about psychoanalytic ideas while being aware of possible unintended negative consequences, such as interference in transference issues with patients, ethical and privacy violations, distortion in the press coverage, unfairly biased antipsychoanalytic coverage, and concern about disapproval from prominent and influential members of psychoanalytic organizations about the nature of the press coverage (or even of press coverage at all) leading to criticism of an individual psychoanalyst and interference with his or her progression. Our public information efforts have to include using misfired efforts as teaching tools and insure that presentation of clinical material is limited and sufficiently disguised.     

Medical Informatics and the Concept of Disease

This paper attempts to address the general questionwhether information technologies, as applied in thearea of medicine and health care, have or are likelyto change fundamental concepts regarding disease andhealth. After a short excursion into the domain ofmedical informatics I provide a brief overview of someof the current theories of what a disease is from amore philosophical perspective, i.e. the ``valuefree' and ``value laden' view of disease. Next, Iconsider at some length, whether health careinformatics is currently modifying fundamentalconcepts of disease. To this question I will answerlargely in the negative, and I will provide the sketchof some arguments from current research programs inmedical informatics why I think this is the case. Thisargumentation is supported by a detailed account ofhow the disease profile for beriberi heart disease,used in one of the major medical informaticsdiagnostic programs, QMR (and its ancestorINTERNIST-1), was developed, and why at least thisprogram essentially follows received views oftraditional medicine.The one main exception to theconformity of this program to ``received' views of adisease occurs when the program's designers need tofine-tune a disease definition. This fine-tuning is tocomport with the expert's perspective on the disease,including his or her epistemic values, as well as theprogram's other resources for diagnosing components ofa disease.