SOC 3020 Lecture Notes - Lecture 2: Normal Distribution, Complex Analysis, Multistage Sampling
Document Summary
Levels of measurement- the mathematical precision with which the values of a variable can be expressed. Ordinal- (quantitative); underlying order in the responses (greater than to less than); the distance between the responses is not known; has a true zero; cannot know actual distance; ordered. Interval- you do know the distance; no true zero; ordered. Ratio- you can multiply and divide; ordered; distance is known; zero has real meaning; if you double it, it equals the doubled amount. Dichotomies- (special case) variable having only two values (measurement) validity- capturing empirical reality. Criterion validity- where you"re correlating your measure with another measure that is already validated or direct. Content validity- relevant when you have a more complex concept; are all the dimensions of the concept represented in the questions: concurrent- at the same time, predictive- in the future. Test-retest- ask at one time then ask again and expect consistent responses; the most common/important kind of reliability;