1. T YPES OF R ELIABILITY AND V ALIDITY Research Methods (cont’d)

2. T YPES OF R ELIABILITY There are four types of reliability measures. For a test/experiment to be deemed ‘ reliable,’ it must yield consistent results no matter the circumstances. Four types: Inter-rater Test-retest Parallel-forms Internal consistency

3. T YPES OF R ELIABILITY ( CONT ’ D ) Inter-rater reliability = the test/experiment yields similar results no matter who is giving the test. This eliminates observer bias. Test-retest reliability = the test/experiment yields similar results across time. Factors that can influence test variation: mood, disruptions, time of day. An unreliable test will vary greatly in results depending on these factors.

4. T YPES OF R ELIABILITY ( CONT ’ D ) Internal consistency reliability = the test/experiment will yield similar results, even though different questions are asked. Questions are different, but material is similar in construct. Example: The following two questions test the same knowledge, although phrased differently. Which social science looks at past cultures and societies? Past cultures and societies are the predominant focus of which social science?

5. T YPES OF R ELIABILITY ( CONT ’ D ) Parallel forms reliability = used to determine the best version of a test/experiment. Different people take different versions of a test at the same time. These two versions are done in parallel, to determine which is best. Example: two field tests are given to students at two different schools on the same day. Whichever test yields more consistent results becomes the nationwide test.

6. T YPES OF V ALIDITY Validity is the extent to which a test measures what it claims to measure. There are 4 main types of validity that are important to sociological research: Construct validity Content validity Conclusion validity Face validity

7. T YPES OF V ALIDITY Construct validity = determines the quality of a test or experiment. Does it measure what it is designed to measure? Content validity = measures what it is supposed to measure AND includes an adequate sample. Does the measurement include different groups or does it focus on the knowledge/characteristics of one specific group?

8. T YPES OF V ALIDITY ( CONT ’ D ) Conclusion validity = a relationship between two variables can be determined, either positive or negative. Face validity = appears to be valid on the surface. This should not be the sole factor in determining validity!!! It can, however, be a good springboard for experimental design– does your experiment seem like it will work?