22LLP207: Research Methods
SPSS 2: Descriptives and Internal Reliability
1. Download the file “P2_career_interests.sav” from the LEARN and open it using SPSS software.
• The dataset contains responses to a “career interests” questionnaire completed by 250 people. People were asked to rate how interested they were in pursuing a career in this job role using a sliding ‘visual analogue’ rating scale running from very low (0) to very high (8). Data source: http://psych.colorado.edu/~carey/courses/psyc7291/ClassDataSets.htm
• There is no missing data or reverse-coded items in this particular dataset
• Also fefer to your lecture slides from Lecture 5 for detailed guidance on performing the SPSS analyses requested below.
• Although we will not be entering and labelling data in this practical exercise, look carefully at how the dataset is set up. Data is entered simply by clicking on a cell and typing it in, just like Excel software, via the “Data View” tab (see the bottom left corner of the screen). Labels are entered by typing in the appropriate cells via the “Variable View” tab (see bottom left corner of the screen).
2. Calculate the means and standard deviations of each of the following variables and write them in the table below to two decimal places.
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Job role
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Mean interest rating
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Standard Deviation
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Carpenter
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Forest Ranger
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Mortician
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Police Officer
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Fire Fighter
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Sales Representative
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Teacher
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Business Executive
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Stockbroker
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Artist
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Social Worker
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Truck Driver
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Doctor
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Vicar
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Actor
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Lawyer
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Architect
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Landscaper
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3. Download the file “Graphs_LLP207.xls” from the LEARN and open it using Excel
4. Draw a line graph of the mean interest rating for each job role, using the appropriate table and graph template in the Excel file. (You may, if you wish, sort the job roles into numerical order of their mean interest rating before graphing them.) Label the graph and its axes.
5. Calculate the Cronbach’s alpha reliability coefficient for each of these psychometric scales and write these in the table below.
6. Compute an overall psychometric scale score for each job family from the mean of the constituent item ratings and save these as new variables, naming each with the appropriate job family label.
7. Calculate the mean and standard deviation for each psychometric scale score and write these in the table below also.
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Job Family
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Cronbach’s alpha (α) for psychometric scale
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Mean psychometric scale score (mean of the constituent item
ratings)
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Standard deviation of the psychometric scale score
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Academic Jobs
· Lawyer
· Mortician
· Doctor
· Stockbroker
· Architect
· Sales Representative
· Business Executive
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Manual Jobs
· Landscaper
· Forest ranger
· Truck driver
· Carpenter
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Caring jobs
· Social worker
· Teacher
· Vicar
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Emergency service jobs
· Police Officer
· Firefighter
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Artistic jobs
· Actor
· Artist
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8. Draw a bar graph of the mean psychometric scale score for each job family, using the appropriate table and graph template in the Excel file. Label the graph and its axes.