Basic Terms and Definitions Flashcards
Descriptive statistics
summarize, understand, and describe a group of numbers from a research study
What are examples of descriptive stats
- measure of central tendency (mean, median, mode)
2. variability (range, varience, sd)
Inferential statistics
- draw conclusions and make inferences based on numbers from a research study, but go beyond these numbers
- if there is a difference between groups
- how sure we are about our conclusions
Variable
condition or characteristic that can have different (varying) values (ex. male/female, …22,23,24…,
Score
the value of a particular person’s answer (ex. male, 25yrs old, 15 sexual partners)
Variability
how much change there is in a group of scores
Variance
a specific measure of variability
Correlational Research Designs
examines if there is a relationship between variables
- “what does knowledge of x tell us about y”
- naturally occurring variables
Experimental Research Designs
goal is to determine why something happens
- “what causes X?”
- control and manipulation of variables
Independent variable
variable that the researcher manipulates/changes
Dependent variable
variable that changes because of IV
Components of an experiment
- Must have more than one level of IV
- several, stable/reliable DVs
- control variables
- random assignment
Control variables
keeping everything else constant
Random assignment
purpose of random assignment is to create equivalent groups
Population
set of all cases of interest, generally a theoretical concept (not always measurable)
Sample
subset of population that is being studied; something to be concerned about is biased samples
Biased Samples
sample that systematically underselects or overselects from certain groups in the population