Homework 5
When submitting this file, be sure the
Be sure you have reviewed this module/week’s lesson and presentations along with the practice data analysis before proceeding to the homework exercises. Complete all analyses in SPSS, then copy and paste your output and graphs into your homework document file. Answer any written questions (such as the text-based questions or the APA Participants section) in the appropriate place within the same file.
The data in the columns to the left represent IQ scores of a sample of 30 high school students. In the general population, IQ scores have a mean of 100 and a standard deviation of 15. Enter this data into SPSS. Be sure to save this file, since you will be using it next week as well.
Generate descriptive statistics for this variable.
Generate a histogram for this variable.
In your data set, standardize the IQ scores by transforming them into z-scores
Label the new variable “ZIQ”
Which z-scores corresponds to a raw IQ score of 115, 79 and 107?
Does the distribution reflect the distribution in the general population?
Support your answer.
1-a)
Generate descriptive statistics for this variable.
Answer: Descriptive Statistics Table
1-b)
Generate a histogram for this variable.
Answer: Histogram
1-c)
In your data set, standardize the IQ scores by transforming them into z-scores under a new variable “ZIQ.” Using your data set as a reference, what z-score corresponds to a raw IQ score of 115?
115
Answer – 0.63131
79
Answer - -1.4474
107
Answer – 0.16938
1-d)
Based on what you have been told about IQ scores in the beginning of the problem,
does this sample’s distribution seem to reflect the distribution of IQ scores in the general population?
Why or why not?
Answer - Yes
Justification
The sample mean and stnardard deviation from the sample are close to the actual population parameters indicated.
A forensic psychologist wants to examine the level of narcissistic personality traits in those who are diagnosed with antisocial personality disorder (ASPD) and those who do not qualify for ASPD within a local prison population. She administers a measure of narcissistic personality traits where higher scores indicate higher levels of narcissism and scores range from 0–35.
Create a new SPSS data file for these scores.
For example, if you code ASPD Diagnosis as 1 and No ASPD Diagnosis as 2, then the SPSS file will appear somewhat like the following:
All ASPD Diagnosis scores from the table above will appear in a similar fashion.
Then, continuing in the same columns, enter No ASPD Diagnosis information as:
[Continue in this fashion to the end of the file]
a) Compute descriptive statistics by diagnosis (that is, for each of the two groups in one table) using similar steps to those covered in Green and Salkind’s Lesson 21 and in the Module/Week 3 presentation (HS GPA scores by Gender).
b) Construct a boxplot to show the difference between the mean scores of the 2 groups
2-a)
Compute descriptive statistics by diagnosis (that is, for each of the two groups in one table) (2 pts)
Answer: SPSS Table- Descriptive Statistics for Score (level of narcissistic personality) grouped by Diagnosis (ASPD/No ASPD):
[Paste one table]
2-b)
Construct a boxplot to show the difference between the mean scores of the 2 groups. (3 pts)
Answer: Boxplot
