A cognitive psychologist has developed a computer simulation of memory processes that generates a simulation of reaction times in response to the presentation of previously learned stimuli.The program has been designed to produce a mean reaction time of 200 msec with a standard deviation of 20.The psychologist is worried that the program has stopped working properly because the last 16 trials have produced a mean reaction time of 190 (with the expected standard deviation of 20).Which of the following statements is true?
A)A z-score could be calculated for these data.
B)A z-score could be calculated for these data but no inferences could be made.
C)A z-score could be calculated for these data but no inferences could be made because it is impossible to get ethical clearance for computer simulations.
D)A z-score could be calculated but it could not be used to make inferences because the population standard deviation is unknown.
E)A z-score could be calculated but it could not be used to make inferences because the population standard deviation is likely to be a negative number.

Question

Quizplus · Accepted Answer

A z-score can be calculated for these data by subtracting the sample mean reaction time (190) from the expected mean reaction time (200) and dividing by the standard deviation (20). However, it is important to note that this calculation assumes that the population standard deviation is known, which may not be the case. Further statistical analysis would be necessary to make inferences about the validity of the program. The statement about ethical clearance for computer simulations is irrelevant and incorrect.

A Cognitive Psychologist Has Developed a Computer Simulation of Memory