The probability of guessing the correct answer rather than knowing the correct answer significantly affects the item statistics and they will be very unstable. Correct answer from the key sheet. Average test score. Standard deviation squared, a measure of spread. Indication of test reliability.
Reliability indicates how well the test measures what it is intended to measure.
It is more likely the observed score falls within a range of values near the true score. Gives the score, frequency of the score, and percent of the class obtaining that score. Observed score, number of items answered correctly. Number of subjects at each score, e.g. 2 students got a score of 16. In order to serve you better and to achieve valid results from evaluation processing, please check the following.