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

Chapter 7 Fill-in-the-Blank Questions
Correlational and Differential
Methods of Research

Now that you have familiarity with the new key terms of this chapter, it is time to begin using the terms in the context of the chapter material. See if you can fill-in-the-blanks in the following discussions. To get the correct answer, click on the blank.

  1. In __________ research, the focus is on the measurement of relationships between variables. In __________ research the focus is on the differences between groups defined by some preexisting variable.

  2. In correlational research, we seek to __________ the strength of a relationship between two or more variables. In many ways, correlational research is an extension of __________ research. In both, variables are typically not manipulated, and a single __________ of participants is typically studied. However, in __________ research, we always have at least two variables and we make a detailed plan of how we will __________ the variables prior to any measurement. Although an observed correlation does not imply __________, observed correlations do serve two useful purposes. A consistent relationship can be used for __________. Observed correlations can also provide data that are either consistent or inconsistent with a particular theory. Although correlational data can never __________ a theory, such data can __________ a theory.

  3. In differential research, we observe two or more groups that are differentiated on the basis of some __________ variable. This classification variable is called the __________ variable. The behavior measured in the different groups is called the __________ variable. The independent variable in differential research is a __________ independent variable, in contrast to the manipulated independent variable characteristic of experimental research. Because differential research involves the study of relationships between variables without any direct manipulation of the variables, differential research is conceptually similar to __________ research. Differential research is structurally similar to __________ research in that performance is measured and compared in two or more groups in both.

  4. When two variables are allowed to vary at the same time, we say that the variables are __________. In such a case we would not be able to tell which of the variables was responsible for an observed change in the dependent measure. We try to control for __________ by holding all variables in which we are not interested constant during the study. We use the term __________ to refer to any apparent effect of a major conceptual variable that was actually the result of some minor uncontrolled variable.

  5. __________ research is used most often when the manipulation of an independent variable is impractical, impossible, or inappropriate.

  6. In __________ research, we seek to measure the strength of a relationship between two or more variables. As in any research project, developing effective __________-__________ for each of the variables in the study is the first step. When collecting the actual data, the researcher must be aware of two sources of bias. The first is the tendency of investigators to see what they __________ to see. The second is the tendency for the investigator to actually __________ the behavior of the participants in subtle ways. This latter effect is know as experimenter __________ . These effects are best controlled by having different investigators collect each measure. In addition to these effects, the participants themselves might influence their own responses by their attempts to appear consistent. This is another example of __________-__________, which was discussed in Chapter 6. This effect is especially strong when participants are aware that they are being observed. To reduce this effect, some researchers try to __________ the measures so that participants are not sure what is being studied. For example, in self-report measures, the researcher might add __________- __________ that are not meant to measure anything, but rather are designed to draw the participant's attention away from the true purpose of the study.

  7. Obtaining a __________ that is representative of the __________ to which we want to generalize is critical. In correlational research, a second sampling issue is whether the __________ between variables is the same in all segments of the population. If we suspect that the relationship may be different in different subpopulations, we should sample each subpopulation separately and compute separate __________ for each subsample. The variable defining such subpopulations is called a __________ variable.

  8. In correlational research, the __________- __________ computed will depend on the level of measurement. If both variables produce score data, a __________-__________- __________ correlation should be computed. If one or both variables is measured on an ordinal scale and neither on a nominal scale, the appropriate coefficient is the __________-__________- __________ correlation. For both of these correlation coefficients, the range is from -1.00 to __________ with __________ representing no relationship. A correlation of +1.00 represents a __________-__________ correlation: As one variable increases, the other variable increases in a perfectly predictable way. A correlation of -1.00 represents a __________-__________ correlation: As one variable increases, the other variable decreases in a perfectly predictable way. We test the correlation for __________-__________ by computing the p-value (the probability of obtaining a correlation that large or larger by chance). This is essentially a test of the null hypothesis that the population __________ is equal to zero. The square of the correlation is the __________-__________- __________, and it represents the "proportion of variance accounted for." If we are working with nominal variables, the appropriate correlation coefficient is _________.

  9. In differential research, the dependent variable is like the variables typical of correlational research. It is usually a __________ measure, but it could also be a discrete measure. In contrast, the nonmanipulated __________ variable is typically a __________ variable.

  10. A central issue in differential research is the selection of groups to study. We use the term __________ group to refer to any group selected in differential research as a basis of comparison with the primary or __________ group. The ideal __________ group is identical to the experimental group on all variables except the __________ variable that defines the groups. In order to select the appropriate control group, we must identify the __________-__________ that might affect the dependent measure. A variable can have a __________ effect in a differential research study only if: (1) it has an effect on the __________ measure(s), and (2) there are differences between the __________ and __________ groups on the confounding variable.