7: Single Factor Designs Flashcards
What is the similarities and differences between Independent groups design and matched groups designs
Both: - Between-subject Design
- Manipulated independent variable
Independent: random assignment
Matched: matching to create equivalent groups
Non equivalent groups design
between-subject
IV is a subject variable
ex post facto
What 4 basic research designs can be called single-factor designs
Independent groups designs
Matched groups designs
Ex post facto designs
Repeated measures designs (within)
What is the advantage of single factor multilevel designs
they allow researchers to discover non-linear effects
they have the ability to address multiple questions and can rule out alternative explanations (can have multiple conditions)
what are the 3 ways to present data for single-factor designs
The numbers can be presented in a sentence form
Construct a table of results including means and standard deviations
Form of a graph
What type of graph do you use for between-subjects vs within subjects
between - bar
within - line
Inferential statistic =
variability between conditions (systematic+error) / variability within each condition (error)
Ideal outcomes with variability is
variability between conditions is large and variability within conditions is small
Inferential statistics can be either
Parametric tests: Tests with certain assumptions (parameters) that are required to best estimate the population
Assumption of homogeneity of variance - the variability of each set of scores being compared ought to be similar
Nonparametric tests:
Used if the assumptions above are violated
What kinds of tests are used for single factor, two level designs
- Independent samples t-test
○ Independent groups design
○ Ex post facto design - Paired t-test
○ Matched groups design
○ Repeated measures design
what do t-tests do
examines the difference between the mean scores for the two samples and determines whether this difference is larger than would be expected by chance alone
○ Parametric
What kinds of tests are used for single factor, multilevel designs
One way analysis of variance (ANOVA)
What are the three kinds of control group designs
Placebo control group designs
wait list
yoked
Describe wait list control group design
Experimental group are in a program because they are experiencing a problem the program is designed to alleviate, wait list controls are also experiencing the problem
describe yoked control group design
Match (yoke) a control with an experimental person so that time spent participating or the types of events encountered is kept constant
