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Recent studies have called for the abandonment of the relative-time-spent scale in task inventories. This recommendation is based on findings that the job profile created with the scale data is highly correlated with the profile created from a much simpler “Do you perform this task?” checklist. We examined this issue using 3 inventories and 42 jobs (N=2252). Profile correlations were computed on only the tasks actually performed by incumbents to avoid possibly inflated rs due to including irrelevant tasks. The specificity of task inventory items was proposed as an explanation for the high correlation between the two job profiles. Specificity of items was examined by looking at both the type (job duties versus tasks) and the amount (number of items in job profile and average number of items relevant to each job) of items used in the inventory. Correlations between time spent and checklist profiles were in the .80's and .90's regardless of the number of irrelevant tasks or the specificity of tasks. We agree with previous military research and conclude that the relative-time-spent scale has limited incremental utility beyond a dichotomous checklist. 相似文献
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Robert Nola 《Journal for General Philosophy of Science》1990,21(2):329-346
In several places Popper describes a little experiment in which an audience is given the non-specific command Observe! He draws a number of conclusions from this experiment, in particular that observation takes place in the presence of theoretical problems, questions, hypotheses or points of view. The paper argues that while Popper's experiment is instructive, it hardly supports the strong conclusions he draws about the theory-dominance of observation in science. In particular, it is argued that talk of principles of selection which guide us to relevant observations, rather than the host of irrelevant observations of the naive inductivist, is misleading. Rather, it is the goals, aims, motives or interests of an observer that guide observation and these need not always involve a theoretical component. 相似文献
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Veatch RM 《The Journal of clinical ethics》1990,1(4):291-292
In this commentary on a study by H. Steven Moffic, et al., of the current status of the Hippocratic Oath in medical education, Veatch discusses the relation of the oath to ethical conduct, the meaning of primum non nocere ("do no harm"), and the limitations of practicing Hippocratic ethics. 相似文献
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John W. Thomas Linda Bol Robert W. Warkentin Mark Wilson Amy Strage William D. Rohwer 《Applied cognitive psychology》1993,7(6):499-532
This investigation focused on the interrelationships among students' study activities, students' self-concept of academic ability ratings, students' academic achievement, and instructional practices in 12 high school biology courses. Using a framework derived from a previous investigation, course features were classified into those that appear to (a) place demands on, (b) support, or (c) compensate for student engagement in particular study activities. Students' study activities, self-concept of academic ability ratings, and achievement were measured with experimenter-developed instruments. Results are reported for (a) characteristics of instruments and course features, (b) relationships between central factors of the investigation, and (c) multi-level relationships between course features and student variables. Results at the student level indicated that self-concept of academic ability and, to a lesser extent, students' study activities were positively associated with student achievement. Students' self-concept of academic ability ratings were also linked to students' engagement in generative, proactive study activities. At the course level the supportive practices of providing challenging homework assignments and extensive feedback on student coursework were associated with student engagement in effortful, generative, proactive study activities. The provision of extensive feedback was also associated with high student achievement. Multi-level relationships were analysed using hierarchical linear modelling (HLM) analyses. These analyses revealed, for example, that in courses in which little or no feedback is given on homework assignments, the relationship between achievement and student engagement in diligent effort management activities was enhanced. Other HLM analyses were conducted to examine the mediating role of course features on the relationship between students' self-concept of academic ability and their study activities and achievement. For example, the presence of challenging course demands was associated with an enhancement of the relationship between self-concept of academic ability and achievement whereas the presence of instructor provisions (supports and compensations) designed to reduce course demands was associated with a reduction in this relationship. 相似文献
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