Question

You have developed a new self-report measure of the broad personality trait of extraversion. Distinguish between reliability and validity, and describe how you would establish the reliability and validity of your new test.

Answer 1

Validity refers to the measuring of instrument which represent the degree to which the scale measures what it is expected to measure.

it is all about the genuiness of the research.

A valid instrument is always reliable.

Assessment isdifficult

Reliability refers to the degree to which measurement produces consistent outcoms

it is the repeatability of the outcomes..

A reliable instrument need not be a valid instrument.

it is easy.

2 Some of the possible methods to establish reliability and validity of your new test is by

• inspecting a test question to see whether they correspond to what the user decides should be covered by the test ie Content validity evidence.
• measuring the legitamacy of new test with the old test. ie Criterion-Related validity evidence.
• Test is given twice and the corelation between the first set of sores and the corelstion betwen the first set of scores and the second set is determined ie test--retest .
• using construct evidence it tells whether the results fro a test correspond to what you would expect tells something about the construct validity for a test.
• Administering alternate forms of a equivalent test to a group of students and the corelation between the two sets of scores is determined.
• Using Iternal consistency which is designed to measure a single basic concept ,which helps to understand whether the students have or have not mastered a particular subject.