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Jason McPherson

Publications and source records attributed to Jason McPherson.

2 recordsLinked to original sources

The role of item extremity in the emergence of keying-related factors: an exploration with the life orientation test.

Keying-related factors in psychological scales are variously interpreted substantively or as products of violations of the assumptions underlying item keying. The present study investigated whether the extremity of the wording of items may contribute to the emergence of item-keying factors in a commonly used psychological scale. Respondents (N = 277) completed the Life Orientation Test (M. F. Scheier & C. S. Carver, 1985) in either its original or modified, more moderately worded form. Results indicate that the interaction of item extremity and item keying significantly affected subscale means and, more important, that the more moderately worded scale was substantially more unidimensional. Results are explained partially through the association of lesser and greater extremity with the tendency for some respondents to agree or disagree with items irrespective of keying direction. These results, although demonstrated in only 1 scale, have potential relevance to any scale comprising positive and negative items.

Adult↗

A speeded coding task using a computer-based mouse response.

This study assessed whether a speeded coding task that used a computer-based mouse response (CBMR) format was a measure of general processing speed (Gs). By analyzing the task within a network of tasks representing both traditional Gs tests and reaction time tasks, it was shown that a CBMR test can be used to measure the same construct as traditional paper-and-pencil (PP) tests and that this response format does not introduce variance associated with psychomotor performance. Differences between PP and CBMR formats were observed, and it is argued that these may provide information on individual differences in performance not available from traditional coding tests.

Adult↗