Psyc 202 - Psychological Research II

Practice problems for Final Exam

A scientist wishes to investigate whether the degree of complexity in a background scene influences people's ability to detect novelty in the foreground of the scene. She defines background complexity in terms of the number of objects present in the background. Therefore, she develops three backgrounds, with either 3, 6 and 9 objects. Since she is also interested in the effects of color three other backgrounds are developed with the same number of objects, but these are in three different colors. After presenting a scene to a subject 10 times, the researcher changes the figure and measures the time (in milliseconds) it takes for the subject to identify the novel object. Subjects are run in a 2 x 3 mixed factorial design with number of background objects as the within subjects variable.

Response time data for each condition are presented below:

Number of Background Objects

3 6 9

Background Color

425 455 510

405 420 465

390 410 450

400 435 520

B/W 430 415 480

445 400 490

420 408 535

385 405 460

430 440 480

450 465 515

435 475 525

420 450 535

395 415 520

Color 445 500 625

400 500 600

425 525 625

390 490 580

410 480 595

2. Fred is interested in social facilitation. Specifically, he wonders if one's performance is influenced by the number and importance of the persons watching. He has 48 high school basketball players at a basketball camp shoot foul shots in the presence of either 2 or 8 observers. One-third of them shoot in the presence of student observers, while one third of the others shoot in the presence of assistant coaches, and the final third shoot in the presence of college recruiters. The number of foul shots made (out of twenty shots) in each condition are listed below:

Importance of Observers

Students Coaches Recruiters

Number of

Observers

18 18 15

20 17 17

15 13 10

Two 16 15 12

17 16 13

19 17 14

20 20 18

20 15 13

15 16 10

18 19 15

16 16 8

Eight 18 17 12

17 16 11

16 18 14

17 16 13