Show Me the Money-Methods

Psych 120 U2

2 types of research design

correlational and experimental studies

correlational approach

Used to examine if and how two sets of observations (variables) are related to one another

correlation coefficient

A numerical index that tells how strongly two sets of observations (variables) are related to one another, and what their relation is like

positive correlation

increases in one variable are associated with increases in the other variable, as one number goes up, so does the other

negative correlation

increases in one variable are associated with decreases in the other variable, as one number goes up, the other goes down

shoe size and intelligence

no correlation

reaction time and age

positive correlation

stress and exercise 

negative correlation

</= .29

modest/weak correlation

.30-.60

moderate correlation

>/= .60 

strong correlation

experimental approach

A series of operations/procedures used to examine possible cause-effect relations between manipulated events and measured events

key issues of experimental approach

Obtaining a random sample, random assignments of subjects to experimental groups, control of extraneous variables, and generalizability of findings