Exam III Flashcards
Alternative (experimental) hypothesis
non-zero effect, can be “directional” or “non-directional”
Null hypothesis
“status quo” or no effect. Examples include No group difference, No relationship between X and Y, No treatment effect
Directional hypothesis
Specifies + or - relationship between IV and DV
Non-directional hypothesis
Indicates a relationship or a statistical effect, but doesn’t specify which way
Research hypothesis
scientific hypothesis, Statement about the expected relationship of the variables, Can be directional or nondirectional
Statistical hypothesis
null hypothesis, States there is no relationship between the variables
Characteristics of “true” design
Manipulation (treatment)
Randomization
Control group
Advantages of pretest design
Equivalency of groups
Can measure extent of change, (May be possible to use within-subject statistics), Determine inclusion, Assess reasons for and effects of mortality
Disadvantages of pretest design
Time-consuming
Sensitization to pre-test
Factorial Design
> 1 IV (factor)
Simultaneously determine effects of 2 or more factors on the DV
ID’d by # of factors and levels of factors
Can include “between” factors & “within” factors
Multivariate statistics are beyond the scope of this class; however, multivariate analyses are:
More powerful
Less prone to Type I errors
Developmental Research Designs (Longitudinal)
Powerful (within subject)
Time consuming
Attrition
Testing effect
Developmental Research Designs (Cross-Sectional)
Less time consuming
Cohorts problem
Soloman four-group design
2 randomized control groups, 1 pretest group and 1 pretest and posttest. Do these at the same time.
Randomized matched control group design
groups are matched, randomized, treatment, posttest
