psychology

2. an unpleasent stimulus between two variables in which one variable increases as the other decreases
3. a sample drawn in such a way that know subgroups within a population are represented in porpotion
4. the factor that is manipulated by the researcher to determine its effect on another variable
6. a tyoe of research in which same people are studied over a long time period
7. the relation between variables
9. people who volunteer to participate in research studies often differ from those who do not volunnteer
11. a prediction or assumption
12. a controlled scientific procedure to determine whether certain variables manipulated by reseacher have an effect on the other variable
13. the study of behavior in a controlled situation
16. a relationship between variables in which one variable increases as the other varibale also increases
17. in an experiment the factor that is being measured and that may change in response to manipulatons of the independent variable
18. factors that are measured or controlled in a scientific study
19. a survey population selected by chance

1. a method of research thet looks at different age groups at the same time in order to understand changes that occur during the life span
3. a representative segment of a target population
5. the study of behavior in naturally ocurring situations without manipulation
8. to repeat a research study
10. the total group to be studied
14. a research technique for acquiring data
15. an in-depth study of a single person or group to reveal some universal principle