Math solutions/problems

Question 1
1. What do we call a number that is generated by dividing ? by the N in a distribution?

Mode

Mean

Median

Range
Question 2
1. If p < .05, then you can assume:

The results are significant

You can reject the null hypothesis

Results more extreme occur fewer than 5 times in 100

All of the above
Question 3
A distribution with two separated peaks is a _____distribution; one that is normal is a ______ distribution.

Bimodal; Rectangular

Rectangular; Bimodal

Bimodal; normal

Normal; Rectangular
Question 4
Taking chance factors into account when you samples to reach conclusions about population is a definition of:

Inferential Statistics

Rationalism

Scales of measurement

Descriptive Statistics
Question 5
A Spearman’s rs examines correlations between ranked data.
True
False
Question 6
With respect to cause and effect statements, a correlation coefficient of 1.00 allows that there may be a cause and effect relationship; a correlation coefficient of .00 indicates that there is no cause and effect relationship.
True
False
Question 7
As a general rule, quantitative research articles are shorter in length because of their deductive approach and use of numbers to express relationships.
True
False
Question 8
A researcher conducted an ANOVA, and the data indicated that there were significant differences between the groups (p < .01). The researcher should conduct a series of independent sample t-tests to determine where the differences in the groups occur.
True
False
Question 9
In general, it is always important to remember the questions that are asked in any study you perform. Virtually everything you do from writing the research design to writing the study’s implications is dictated by the research questions.
True
False
Question 10
An independent samples t-test is a nonparametric test because it features means and standard deviations?
True
False
Question 11
The __________ distribution occurs when the mean, median, and mode are the same.
Question 12
For what purpose do scholars use a Pearson’s Product Moment r?

Question 13
A researcher computes an independent sample t-test, and determines that p < .05. What does this mean?

Question 14
Describe parametric tests.
Question 15
Describe the ANOVA.

Question 16
A professor is interested in knowing the correlation, if any, of students’ scores on the first and second exams given in his class.

Test 1 Test 2
92 86
90 87
89 85
82 90
88 79
92 90
100 92
91 84

Select the correct statistical test; perform the test; report the results according to the handbook guidelines; explain what the results mean to the professor.

Question 17
With respect to the situation in question 16, what other test could the professor use that would yield valid results by looking for differences between the student’s performance on the first and second exam?

Select the correct statistical test; perform the test; report the results according to the handbook guidelines; explain what the results mean to the professor.
Here is the data again:
Test 1 Test 2
92 86
90 87
89 85
82 90
88 79
92 90
100 92
91 84

Question 18
Now, let’s look at a situation in which we compare three college math teachers to each other with respect to how interested they keep their students. The study was conducted among freshmen enrolled in an introductory course. The unit was quadratic equations. Students were asked to jot down an x on a piece of paper every time they found their attention drifting away from the lecture. What test or tests would you use to rule out chance from causing the apparent differences in these data?
Here are data from one fifty minute lecture:
Teacher A Teacher B Teacher C
5 9 4
5 7 4
7 4 6
4 7 5
6 8 6
6 7 5
5 4 4
5 5 6
43 51 40
Select the correct statistical test; perform the test; report the results according to the handbook guidelines; explain what the results mean.

Question 19
1. In a study by Latane and Dabbs (1975), an experimenter entered hundreds of elevators and accidently dropped a bunch of pencils. Some bystanders helped pick them up and some did not. Of the 1303 females, 300 helped. Of the 1320 males, 370 helped. (Was gender related to helpfulness?). Select the correct statistical test; perform the test; report the results according to the handbook guidelines; explain what the results mean.

Question 20
A researcher examines factors that affect thinking. In one study, she had three groups of participants work on seven problems that required creative thinking. One group prepared for the task by exercising; a second group watched a comedy video; the third group was a control group that simply began work on the problems. The scores below show the number correct for each participant.
Exercise Comedy Control
5 4 4
4 7 2
1 6 1
2 5 1
3 3 3
0 4 2
2 7 0

Select the correct statistical test; perform the test, and any subsequent post-hoc tests; report the results according to the handbook guidelines; explain what the results mean.