Define cross-sectional and longitudinal designs.
Cross-sectional: is a research method where data are collected at the same time from people in different age categories.
Longitudinal: the study of changes in individual or group behavior over an extended period of time by repeatedly monitoring the same subjects.
What is a factor?
An independent variable.
Shawn wants to assess the linear relationship between two variables. What type of statistical analysis should he use?
A Pearson Correlation.
____ and _____ are the two broad categories of sampling methods.
Non-probability and Probability sampling
This characteristic is absent from quasi-experimental designs.
What is random assignment. Attempts to minimize threats to internal validity.
Sampling effects our ability to generalize our results from the sample to the population. This is also known as______ validity
External
Name and define two (2) types of probability sampling methods.
Simple random sampling- coin flip, or random number generator.
Systematic random sampling- Every nth person.
Stratified random sampling- sampling subgroups proportionately, then random sampling.
Cluster sampling- regional sampling (zip code, city, etc), then random sampling.
DAILY DOUBLE!!
A research study is conducted to determine if Zoloft decreases depressive symptoms. The study assigns participants into two groups. One group receives a placebo and the other group receives 75 mg of Zoloft. What are the independent and dependent variables? What type of statistical analysis should be conducted?
Dependent variable- Depressive symptoms.
Independent variable- Medication/Treatment (Zoloft and placebo).
Independent samples T-test.
Dr. McDowell wants to compare the means between two groups in her study. What kind of data analysis should she use?
Independent- samples t-test
In this type of sampling, the researcher uses participants to find other participants. 1.)What is it?
2.) What is a potential threat to validity with this sampling method?
Snowball sampling. Selection threat, because participants are likely to find people similar to themselves( i.e. friends and family)
Name and define 2 characteristics of a non-experimental design.
A design that produces groups of scores that can be compared for significant differences.
A nonexperimental design makes little or no attempt to minimize threats.
Annie is studying the relationship between dating and personality. She visits a local mall and asks shoppers to complete her questionnaire. What kind of sampling method is she using?
Convenience Sampling
What are three concerns when constructing a survey? What three things should a survey researcher keep in mind when creating a survey?
Keep items simple and unambiguous, and ?avoid double negatives. ? Avoid double-barreled (compound) questions that require responses about ?two or more unrelated ideas. Use exhaustive response choices. Make questions interesting Ask important questions early on.