## PSYC 354 Homework 2

Use the following table to answer Question 1. This table depicts the scores of 40 students on an exam worth 100 points.

1) Use the information in the table to determine the percentages for each interval. Depending on your rounding

decisions, these may or may not add up to exactly 100% but should be very close.

Table: Grouped Frequency Table

Score Interval

Frequency

Percentages for each Interval

90-100

9

?

80-89

10

?

70-79

9

?

60-69

5

?

50-59

4

?

40-49

2

?

30-39

1

?

TOTAL

?

?

2) ________ look like bar graphs but typically display scale data.

3) A frequency distribution that is bell-shaped, symmetrical, and unimodal is ____________.

4) A frequency distribution that has a tail trailing off to the right of the distribution is ____________- skewed.

5) A frequency distribution of ages of residents at an assisted living facility is clustered around 81 with a long tail to the left. This distribution is ____________-skewed.

6) When a constraint prevents a variable from taking on values above a certain point, this is known as a(n) ________ effect.

7) There are two types of graphs that are best to use when graphing two scale variables. Which two graphs are these? _________ and __________

8) When graphing a nominal independent variable and a scale dependent variable, you could use a ________ or a _________.

9) When graphing a single scale variable you should use which type of graph? _________

10) A grouped frequency table has the following intervals: 0–19, 20–39, and 40–59.

If converted into a histogram, what would the midpoints be? The process of determining midpoints is best outlined in Example 2.3 of Chapter 2, and illustrated in Ex. 2.4.

30–39: Midpoint Value

40–49: Midpoint Value

50–59: Midpoint Value

11) Do the data in the scatterplot below show a linear relation, non-linear relation, or no relation at all?

Answer

12) Do the data in the scatterplot below show a linear relation, non-linear relation, or no relation at all?

Answer

Part II: SPSS Analysis

Green and Salkind, Lesson 20

• Open the “Lesson 20 Exercise File 1” document (found in the course’s Assignment Instructions folder) in order to complete these exercises.

• Always use the Blackboard files instead of the files on the Green and Salkind website as some files have been modified for the purposes of this course.

• Reminder: For Exercise 1, be sure to paste in the SPSS output and write out the answers for A, B, and C beneath it.

Part II:

Questions 1-4

• Ann wants to describe the demographic characteristics of a sample of 25 individuals who completed a large-scale survey.

• She has demographic data on the participants’:

♣ Gender (two categories)

♣ Educational level (four categories)

♣ Marital status (three categories)

♣ Community population size (eight categories).

Questions 1a -1c

1) Conduct a frequency analysis on the gender and marital status variables. From the output, identify the following:

a. Percentage of women

b. Mode for marital status

c. Frequency of people who have never been married in the sample

Answer- Table- Gender: (paste Table in this cell)

Answer- Table- Marital Status: (paste Table in this cell)

1-a) Percentage of women: Answer

1-b) Mode for marital status (give the name of the group, not the number): Answer

1-c) Frequency of people who have never been married: Answer

Questions 2-4

2) Create a frequency table to summarize the data on the educational level variable.

Answer- Table- Education Level: (paste Table in this cell)

3) Create a bar chart to summarize the data from the community population variable.

Answer- Bar chart – Community population: (paste Bar chart in this cell)

4) Write a Participants section describing the participants in Ann’s sample. You may refer to the tables you have created above within the section.

Answer- Participants Section:

Part III: SPSS Data Entry and Analysis

The steps will be the same in Part III as the ones you have been practicing in Part I of the assignment; the only difference is that you are now responsible for creating the data file as well. Remember to do the following:

• Name and define your variables under the “Variable View,” then return to the “Data View” to enter the data; and

• Paste all SPSS output and graphs into your homework file at the appropriate place.

Part III:

Questions 1a-1c

• This question is based on the data in the end-of-chapter Question 2.30 of the Nolan and Heinzen textbook.

• Create a variable called “num_years” in a new SPSS file.

• Enter the data given in #2.30.

o Remember to enter the data into 1 column (variable).

1-a) Create a frequency table in SPSS for these data.

Answer- Frequency Table- Number of Years:

(paste Table in this cell)

1-b) Create a histogram for these data.

Answer- Histogram – Number of Years:

(paste Figure in this cell)

1-c) How many schools have an average completion time of 10 years or less? (Each number in the file represents one school.)

An average completion time of 12 years or more?

Answer for 10 years or less =

Answer for 12 years or more =