final exam Flashcards
define: non-experimental research
a research strategy that involves determining whether an association exists between variables by comparing two or more groups of participants that represent different values of one variable to see if the groups also differ on another variable
define: quasi-independent variable
a predictor variable in non-experimental or quasi-experimental research
define: quasi-experimental research
A research strategy that involves varying the levels of one variable and measuring another variable, but that lacks the control needed to establish a cause and effect association between variables
true or false: quasi-experimental research involves more control/manipulation than non-experimental
true
the term non-experimental research specifically refers to research looking at the difference between ____ ____ of two or more groups of participants
mean scores
why is the association between variables that has been established through non-experimental group comparisons sometimes described as correlational research?
because of lack of control
true or false: some sources categorize quasi-experimental, correlational, and descriptive research all as types of non-experimental research
true
what types of designs can refer to both non-experimental and experimental group designs?
- between subjects designs
- within subjects designs
what types of statistical analysis can be used for between subjects and within subjects designs?
- t-test
- ANOVA (analysis of variance)
define: non-equivalent group designs
a study in which the different groups of participants are not randomly assigned to groups and are therefore considered not to be equivalent
what is a threat to internal validity in non-equivalent group designs?
individual differences
what are the 3 types of non-equivalent group designs and define them
- differential research designs = a study that compares a dependent variable between two or more pre-existing groups of participants (ex: self-esteem and academic performance - cannot randomly assign people to have different levels of self-esteem)
- Post-test only non-equivalent control group design = a study that compares a dependent variable (outcome) between a group of participants who received a treatment and a group of participants who did not receive treatment
- Pretest-posttest non-equivalent control group design = a study that compares a dependent variable (outcome) between a group of participants who received a treatment and a group of participants who did not receive a treatment
what does a pre-test control?
time related variables
what type of design is a non-equivalent group design?
a between subjects non-experimental group design
what is a within-subjects non-experimental group design?
pre-post design = a study that compares a dependent variable (outcome) measured in one group of participants before and after they receive an intervention (no control group is used)
why is a pre-post design considered a within-subjects experimental group design?
because it’s the same group of participants who is measured on the dependent variable two (or more) separate times
what are the three types of pre-post designs and define them
- Pretest-posttest design = each individual is measured only once before and once after treatment
- Time-series design = each participant is measured multiple times before and after treatment
- Interrupted time-series design = the “intervention” is not manipulated by the researcher
define: developmental research designs
Research designs used to evaluate changes that occur as people get older
what are the 2 types of developmental research designs and define them
- Cross-sectional design = a research design in which people of different ages are compared at the same point in time
- Longitudinal study design = a research design in which the same participants are studied over time using multiple measurements - individual differences do not provide an alternative explanation for results
another term for an independent variable is a ___
factor
define: factorial design
a research design that includes two or more independent variables (factors)
define: two-factor design
a study with two independent variables
define: higher-order factorial design
a study with three or more independent variables
why do we use factorial designs?
- Humans are complicated and influenced by a variety of factors
- Allows us to look at factors acting together that uniquely affect behaviour in ways that are different from either factor acting alone
what is the simplest form of a factorial design?
2 independent variables with 2 levels = 4 different study conditions with their own means
what is a 2 factor design?
2 levels of the first independent variable times 3 levels of the second independent variable