
MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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Transcribed Image Text:When attempting to predict job performance using personality traits, researchers typically assume that the
relationship is linear. A study investigated a curvilinear relationship between job task performance and a
specific personality trait-conscientiousness. Using data collected for 602 employees of a large public
organization, task performance was measured on a 30-point scale (where higher scores indicate better
performance) and conscientiousness was measured on a scale of -3 to +3 (where higher scores indicate a
higher level of conscientiousness).
1. The coefficient of correlation relating task performance score to conscientiousness score was reported as
r = 0.18. Explain why the researchers should not use this statistic to investigate the curvilinear relationship
%D
between task performance and conscientiousness.
2. Give the equation of a curvilinear (quadratic) model relating task performance score (y) to conscientiousness
Score (x).
3. The researchers theorized that task performance increases as level of conscientiousness increases, but at a
decreasing rate. Draw a sketch of this relationship.
4. If the theory in part (3) is supported, what is the expected sign of the quadratic term in the model, part (2)?
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