Opportunity to find supporting evidence, support/disprove concepts/theories. Variable: a concept that can take on more than one value. : ex. values in the concept of gender- male, female, other, prefer not to say, this is a concept that may vary. Independent variable: the presumed cause in a cause-and-effect relationship (x) Dependent variable: the presumed effect in a cause-and-effect relationship (y) Correlation: visible relationship between x and y, however you can not say x causes y. Population: the entire group about which the researcher wants to generalize: ex. Sample: the part of the population of interest that is selected for analysis. How do you sample: probability and non-probability sampling techniques, probability (mathematically random) - everyone has equal likelihood of being selected into the sample- quantitative methods (numbers, non- probability- qualitative data (words, images, non-numerical) Methods: experiments- testing cause and effect, control group + experimental group, best method to establish causation, con-artificial setting.