Ninth Edition CoverGraziano & Raulin
Research Methods (9th edition)

Chapter 10 True/False Questions
Single-Variable, Independent-Groups Designs

Challenge yourself with these true/false questions. Click on your choice to see if you are correct.

  1. An experiment must include at least three levels of the independent variable. (True/False)

  2. The term "experimental design" refers to both the activity involved in the planning of an experiment and the product (i.e., the detailed plan itself). (True/False)

  3. In an experiment, the independent variable is actively manipulated by the researcher. (True/False)

  4. Extraneous variance refers to the variability due to the effects of the independent variable. (True/False)

  5. Controlling extraneous variance will tend to increase internal validity. (True/False)

  6. Significantly high experimental between-groups variance is necessary in order to support the research hypothesis that the independent variable influenced the dependent variable as predicted. (True/False)

  7. The largest single source of experimental variance is extraneous variance. (True/False)

  8. Experimental variance results from the combination of individual differences and the effects of confounding variables. (True/False)

  9. Our purpose in experimental design is to maximize the experimental variance and control the extraneous variance. (True/False)

  10. The term "error variance" refers to the nonsystematic, within-groups variability. (True/False)

  11. In a well-designed experiment, error variance can be held to zero. (True/False)

  12. Extraneous variance results from the same random errors that contribute to error variance. (True/False)

  13. The F-ratio is computed by taking a measure of within-groups error variance and dividing it by a measure based on the between-groups variation. (True/False)

  14. If there are no systematic effects in the experiment, the F-ratio should equal zero. (True/False)

  15. A manipulation check is useful to verify that the independent variable is indeed varied. (True/False)

  16. One way of controlling extraneous variance is to use different measuring procedures in each of the experimental conditions. (True/False)

  17. Randomly assigning participants to conditions is one way of controlling extraneous variance. (True/False)

  18. An unreliable measuring instrument will increase the level of error variance. (True/False)

  19. The critical characteristic in ex post facto studies is the manipulation of the independent variable by the researcher. (True/False)

  20. The distinction between the ex post facto study and the single-group, posttest-only study is whether or not the independent variable is manipulated. (True/False)

  21. Both maturation and history are possible confounding variables in the single-group, posttest-only design and the single-group, pretest-posttest design. (True/False)

  22. Adding the pretest, as in the single-group, pretest-posttest design, allows us to rule out regression to the mean. (True/False)

  23. In the pretest-posttest, natural control-group design, participants are randomly assigned to the experimental and control conditions. (True/False)

  24. Two factors that distinguish experimental designs from most nonexperimental designs are the addition of one or more control groups or conditions and random assignment of participants to the groups or conditions. (True/False)

  25. Random assignment of participants to groups will help protect external validity. (True/False)

  26. The randomized, posttest-only, control-group design does control for history and maturation, but does not control for selection. (True/False)

  27. A randomized, pretest-posttest, control-group design provides greater assurance than a randomized, posttest-only, control-group design that the two groups are equivalent on the dependent variable at the start of the experiment. (True/False)

  28. The multilevel, completely randomized, between-subjects design is an extension of a simpler experimental design for the situation in which there are more than two groups. (True/False)

  29. The t-test and the analysis of variance evaluate different aspects of the data. (True/False)

  30. The t-test should be used in situations in which there are two or more groups to be compared. (True/False)

  31. The analysis of variance (ANOVA) will evaluate the differences in variance between two or more groups. (True/False)

  32. The total sum of squares is equal to the sum of the between-groups sum of squares and the within-groups sum of squares. (True/False)

  33. If there are no systematic between-groups differences, the mean square between-groups will be approximately equal to the mean square within-groups. (True/False)

  34. The larger the systematic between-groups variance, the smaller the F-ratio. (True/False)

  35. A significant F-ratio means that all of the groups are different from one another. (True/False)

  36. In order to find out which groups are different from which other groups when an F-ratio is significant, specific means comparisons must be made. (True/False)

  37. Factorial designs are a special case of within-subjects designs. (True/False)

  38. A chi-square test is typically used with nominal data. (True/False)

  39. Most independent variables at the experimental level generate nominal data. (True/False)