Data Collection Methods 1. Self-Report Methods People are asked to rate/describe their own behavior Questionnaires/Interviews/Introspection (personal observation of feelings, perceptions, and thoughts) 2. Observational Methods Researchers observe & record subjects' behavior Tests Naturalistic observations (unobtrusively watch people) Hawthorne effect: People change behavior when they know they are being watched Solution: Habituation (get used to it and engage in normal behavior) Both have limitations. Each data collection method has advantages & disadvantages. Statistical Methods Descriptive Statistics (Summarize data) Median: Center score = arranging scores & finding score that has the same amount of numbers above as below Mean: Arithmetic average = adding scores & dividing sum by the number of scores Variability: Degree to which the numbers of the sets differ from one another Inferential Statistics (Likelihood of them not being result of chance) Correlation Coefficient -1.00 -0.50 0 0.50 1.00 Scatter Plot Moderate Positive Correlation Strong Positive Correlation Correlation Coefficient is close to or equal to 0 = No Correlation P = Level of Significance / Probability that results occurred solely by chance If P ≤ 0.05, results are labeled as statistically significant The bigger the group of observations, the higher the chances of being significant The bigger the group of observations, the higher the chances of being significant