University of Phoenix Material
Week Two Practice Problems
Prepare a written response to the following questions.
12. For the following scores, find the mean, median, sum of squared deviations, variance, and standard deviation:
1,112; 1,245; 1,361; 1,372; 1,472
M= (( = 6,562 = 1312.4
Sum of squared deviations:
((X-M)2 or SS
(1,112-1,312.4)2+ ((1,245-1,312.4)2 + (1,361-1,312.4)2 + (1,372- 1,312.4)2 + (1,472-1,312.4)2 = 76,089.2
SD2 = SS = 76,089.2 = 15,217.84
SD = √SD2 = √15,217.84 = 123.3606
16. A psychologist interested in political behavior ...view middle of the document...
For example, the standard deviation for the U.S. governors is √35 = 5.92.
Note the waus in which the means and standard deviations differ, and speculate on the possible meaning of these differences, presuming that they are representative of U.S. governors and large corporations’ CEOs in general.
The mean is about the same for the U.S. governors and CEOs. The standard deviation is twice as wide for the CEOs indicatin the CEOs can either have much larger or much smaller desks then the U.S. governors. The disparity of square footage of the desks belonging to CEOs is much wider than U.S. governors.
21. Radel and colleagues (2011) conducted a study of how feeling overly controlled makes you desire—even unconsciously—more freedom. In their study, 52 Canadian undergraduates played a video game in a laboratory and were randomly assigned to either:
a. an automony deprivation condition, in which they were told to follow instructions precisely, constantly given instructions over a loudspeaker, and carefully observed on everything they did.
b. a neutral condition, which was much more laid back.
After this activity, they were asked to do a “lexical decision task” (a standard approach for measuring unconscious responses) in which they were shown a series of words and nonwords in random order and had to press “C” if it was a real word or “N” if not. Half of the real words were related to autonomy (e.g., freedom, choice) and half were neutral (e.g., whisper, hammer). The key focus of the study was on how long it took people to press the button *(“response latency”) for each kind of real word, averaged over the many words of each type. The table below shows the mean and standard deviation across the participants of these four categories of results. Thus, for example, 782 milliseconds (thousandths of a second) is the average time it took participants in the autonomy-deprived condition to respond to the autonomy-related words, and 211 is the standard deviation across the 26 participants’ average response time in that condition. Explain the numbers in this table to a person who has never had a course in statistics. (Be sure to explain some specific numbers, as well as the general principle of the mean and standard deviation.) For your interest, the pattern of results shown here supported the researchers’ hypothesis: “Relative to a neutral instructional climate, a controlling climate thwarting the need for autonomy…enhanced accessibility for autonomy-related words.” (p.924).
|Mean Latencies (in Milliseconds) in the Lexical Task Assessing Accessibility for Autonomy-Related Constructs (Experiment 1) |
| |Condition ...