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251.
Johnston JM 《The Behavior analyst / MABA》1988,11(1):1-9
A comparison study is an experiment whose primary purpose is to compare directly (regardless of experimental design) at least two different procedures for changing behavior or two or more components of such a procedure. This paper argues that, in spite of their popularity, such studies typically lead to inappropriate inferences with poor generality based on improper evidence gathered in support of the wrong question, thus wasting the limited experimental resources. The discussion considers problems concerning the functions of comparison studies, the nature of the comparisons that are attempted, the generality of their findings, and the limited role that they can play in technological research. 相似文献
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Ellen J. Frank 《Sex roles》1988,19(1-2):107-118
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In contrast to theoretical discussions about potential professional liability of clinical ethicists, this report gives the results of empirical data gathered in a national survey of clinical medical ethicists. The report assesses the types of activities of clinical ethicists, the extent and types of their professional liability coverage, and the influence that concerns about legal liability has on how they function as clinical ethicists. In addition demographic data on age, sex, educational background, etc. are reported. The results show that while nearly one third (28.9%) of the ethicists regularly make recommendations about patient care, only 10.8% of them regularly make entries in the medical record; only approximately half (53.0%) of them are covered by professional liability (malpractice) insurance; and the vast majority (84.3%) of them say that concerns about legal liability do not influence the way they function as clinical ethicists. 相似文献
259.
John Polich Maung Aung Donald J. Dalessio 《Integrative psychological & behavioral science》1988,23(1):35-40
Experiment 1 elicited the P1, N1, P2, and N2 components of the long latency auditory evoked potential (AEP) using a 1000 Hz tone presented at 30, 50, or 70 dB SPL and 1-, 3-, or 5- second inter-stimulus intervals to assess the relative effects of the combination of these variables on component amplitude and latency. Four blocks of 16 tone presentations each were recorded from each subject to determine if changes in the AEP would occur because of short-term habituation. Both stimulus factors interacted significantly in a systematic fashion for the amplitude measures, with increases in latency also associated with increases in intensity and inter-stimulus interval. Only minor changes across the four trial blocks for either the amplitude or latency measures were observed over the various stimulus presentation conditions. Experiment 2 employed the same tone stimulus presented at 50 dB SPL and a 3-second inter-stimulus interval. Eight blocks of 64 trials were recorded from each subject on each day for four days to investigate long-term habituation effects. No substantial changes in any of the component amplitudes or latencies were obtained across the 32 trial blocks. It was concluded that intensity and inter-stimulus interval interact to determine AEP amplitude as well as latency values and that the constituent components do not change appreciably with repeated stimulus presentations, even after several days. 相似文献
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W. J. Jacobs M. Buttrick D. Kennedy 《Integrative psychological & behavioral science》1988,23(1):29-34
The present study outlines a rapid and sensitive on-the-baseline conditional emotional response (CER) procedure. Using rats as the experimental subject, the method detects delay conditioning, incubation, extinction and spontaneous recovery. In addition, the method detects conditional responding using electric shock ranging from 0.23 to 0.50 mA as the unconditional stimulus. Because of its speed and sensitivity, the method shelters the subject from unnecessary long-term deprivation and pain. 相似文献