Assignment 2 hit false rate

# Assignment 2 hit false rate - there is a higher chance of...

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PSYC 4165 Homework Assignment 2 Part 1: A: HR = 104/150 = 0.6933333 FAR = 92/300 = 0.3066667 d’ = qnorm(0.6933333) – qnorm(0.3066667) = 1.010642 B: HR = 126/150 = 0.84 FAR = 150/300 = 0.5 d’ = qnorm(0.84) – qnorm(0.5) = 0.9944579 In this situation I would prefer the radiologist with the highest hit rate, radiologist B. This means there is a higher chance of being told I have cancer when I don’t. However in the case of a serious illness such as cancer where treatment success increases dramatically with early detection, this is a chance I am very willing to take when
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Unformatted text preview: there is a higher chance of detecting a real cancer. Part 2: Signal Detection ROC 0.2 0.4 0.6 0.8 1 0.2 0.4 0.6 0.8 1 False Alarm Rate Signal Detection Distribution-2.5-1.5-0.5 0.5 1.5 2.5-2.5-1.5-0.5 0.5 1.5 2.5 False Alarm Rate Z-Score This data set appears to be very well represented by a Gaussian signal detection model. The Receiver Operating Characteristic closely follows the bowed shape predicted by the model. In addition, the z-scores of the FAR and HR follow the straight line equation predicted by signal detection theory....
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## This note was uploaded on 04/03/2008 for the course PSYC 4165 taught by Professor Harvey,lew during the Spring '08 term at Colorado.

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