Sometimes researchers cannot manipulate some of the variables they are most interested in (e.g., having thyroid cancer). We use naturally occurring groups. This form of research is known as ______.

According to Steven Johnson, today's video games do all of the following EXCEPT

a. require intense problem-solving to complete. b. often require the players to figure out the rules by themselves. c. offer simple, repetitive visual experiences. d. being too violent or sexual in their content.

When Jerry thought he was the only person who was assigned the job of contacting alumni for a 15-year reunion, he spent several hours on the phone each evening trying to reach members of his graduating class. When he learned that eight other people were also working on contacting the alumni, he spent only 30 minutes each night making phone calls. The process that would BEST explain the decrease

in Jerry's effort when he learned that he was working as part of a larger group, is a. social interference. b. social loafing. c. the bystander effect. d. social dissonance.