Correlations and Experiments

correlations

variable related, uses scatter plots, and if you change one thing everything will change

“r”

symbol for correlation coefficient

direction of (+)

going the same direction

direction of (-)

going opposite directions

if “r” = 0

no relationship

what “r” can’t equal

over +1 or -1

weak correlation

“r” = .1 to .3

moderate correlation

“r” = .4 to .6

strong correlation

“r” = .7 to .9

perfect correlation

+1.00 or -1.00

illusory correlation

not related, but we have come to terms with it(eg. superstitions)

regression towards the mean

an extreme point in the data(outlier); after an extreme result, the data will go back down to the average

experiment

research method where an investigation manipulates one more more factors to observe the effects on some behaviors

independent variable

factor that can be altered, manipulated

dependent

gets effected by the altered data, measured

control group

not exposed to anything

experiment group

gets the independent variable

placebo group

exposed to false information, eliminates participant expectations