Exam 17: Tests and Measurements

The test re-test method is used to assess a test's validity.

A researcher wishes to estimate the reliability of the new test of a person's sense of humor, the LOL test (Lambda Orientation Level). The test is composed of a total of 40 items, and the researcher splits the scoring in order to compare each subject's score on the odd numbered items with those on the even numbered items. A total of 10 adult males was randomly selected and their scores were as follows: Odd Even Subject \# 1 15 17 2. 10 13 3. 5 8 4. 8 8 5. 12 12 6. 13 13 7. 7 10 8. 10 8 9. 11 12 10. 9 9 Estimate the reliability of the whole test.

The split-half method can be used to assess a test's

The reliability of a certain test is .90, whereas the reliability of the criterion is .85. What is the highest possible validity value for this test?

When test scores have been shown to accurately predict later performance, then the test is considered to have

Is the test proving to be reliable? .

A forensic psychologist is attempting to assess the validity of a new test of police aptitude. The test is given to a random sample of first-day trainees during their orientation session at the police academy. At the end of the 2 month training program each subject is evaluated by the academy's director and rank-ordered on the basis of overall proficiency. The data follow. Subj\# Test Score Ranking 1 55 8 2 60 3 3 45 6 4 75 2 5 43 5 6 34 10 7 48 7 8 62 1 9 50 4 10 46 9 -Find the Spearman correlation.

An attempt to determine whether a given item separates the high from the low performers on the overall test is called the

An item would be considered extremely difficult if it had a difficulty index of

In order to predict how much an individual's score might change on a retest, we can use the

A method for assessing the overall reliability of a test by splitting it into all possible halves is called the

Was the test statistically valid?

A test constructor is interested in determining the reliability of a certain item on a new test of aggressiveness, the ASAP (Aggressive Syndrome Assessment Profile). The items were scored 1 for showing aggressiveness and 0 for passivity. For each subject, the total score on the test is reported, high scores indicating higher levels of aggressiveness. Subj Item Score Total Score Subj Item Score Total Score 1. 1 10 2. 1 12 3. 1 10 4. 1 11 5. 1 15 6. 0 4 7. 0 5 8. 0 6 9. 0 9 10. 0 7 Find the point-biserial reliability value for the selected item.

For the majority of the items in any given test, the difficulty index should be kept at approximately

A forensic psychologist is attempting to assess the validity of a new test of police aptitude. The test is given to a random sample of first-day trainees during their orientation session at the police academy. At the end of the 2 month training program each subject is evaluated by the academy's director and rank-ordered on the basis of overall proficiency. The data follow. Subj\# Test Score Ranking 1 55 8 2 60 3 3 45 6 4 75 2 5 43 5 6 34 10 7 48 7 8 62 1 9 50 4 10 46 9 -17-75, Is it significant? .

The correlation between the odd and even numbered items for a given test underestimates the test's reliability unless corrected for by a technique such as the Spearman-Brown prophecy formula.

Unless the Spearman-Brown is used, split-half reliability values tend to be

A psychologist wants to assess the reliability of a new test of Self Control, the higher the scores the higher the level of control. A random sample of college students is selected and given the test. In order to tap the reliability, the test is scored on the basis of comparing the results of the odd items versus the even items. The data follow: Subject\# Odd Even 1 45 57 2 50 48 3 35 57 4 62 55 5 55 60 6 38 50 7 55 50 8 45 38 9 65 70 10 55 50 -Is it significant? .

A researcher wishes to establish the DI (Discrimination Index) for a series of five items contained in a new test being developed to assess Whole Language Readiness (WLR). The data are as follows: Item Proportion Correct Proportion Correct $\quad$ $\quad$ $\quad$ For Top Third For Bottom Third a. $\quad$ $\quad$ $\quad$ $\quad$ .70 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ .60 b. $\quad$ $\quad$ $\quad$ $\quad$ .70 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ .50 c. $\quad$ $\quad$ $\quad$ $\quad$ .50 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ .20 d. $\quad$ $\quad$ $\quad$ $\quad$ .95 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ .70 e. $\quad$ $\quad$ $\quad$ $\quad$ .45 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ .50 For Top Third For Bottom Third

Correlations that are used to assess reliability typically result in lower values than those used to assess validity.