Can a study be both observational and correlational?

• Describe participants' responses and identify relationships among variables

Most research studies attempt to both describe and predict behavior and mental processes by observing behavior directly and/or by asking participants to complete surveys. When researchers gather information for several variables, they often look to see whether there are relationships among the variables. An example may help to clarify this.

In one study, researchers were interested in finding out whether people notice significant changes in their environment (Simons & Levin, 1998). They had a confederate — a person who helps the researcher create a research situation for observation" ask individuals on a college campus for directions. Midway through the conversation, the confederate was replaced by a different person. Simons and Levin observed and recorded their variable: whether people in their study noticed the change (yes or no). Would you detect the change?

How did they accomplish this magic act? The confederate first approached a stranger on a campus sidewalk and asked for directions to a campus building. As they talked, two additional confederates rudely walked between them carrying a door. The unsuspecting research participant could see the door, but could not see the two people carrying the door. As the door interrupted the conversation, the first confederate (who had asked for directions) switched places with a person carrying the door. The new confederate then continued the conversation and noted whether the research participant noticed the switch.

To see a video of the change, go to http://www.wjh.harvard.edu/~viscog/lab and check out the Demonstrations section.

Many people did not notice the change. So, we can describe people's behavior by saying that people often miss important changes. Can we make a prediction too? To make a prediction, we need to observe a relationship between two variables. Simons and Levin observed a second variable. Whether participants noted the change depended on whether the confederate was similar to the participant or not similar (e.g., same age or different age). People detected the change when the confederate was similar, but were less likely to detect the change when the confederate was dissimilar. Based on these findings, we can predict when people will detect changes.

In sum, if your research question seeks to describe and/or predict an aspect of behavior or mental processes, you should use an observational or correlational research design.