Understanding SPSSBrandon Aragon, Research Technician

Eric Cazares, Graduate AssistantClaudia Alvarado, Graduate Assistant

2015-16 Workshop SeriesOctober 20, 2014

Office of Institutional Research (IR)• Accountability

• Internal• External

• Assessment• Continual Improvement Support• Surveys and Measures

• Planning• Enrollment Management/Resource

Allocation• Decision-making and Policy

Formation

• Research• Qualitative and Quantitative Research• Dissemination

• Visit us at: http://ir.csusb.edu

IR Staff• AVP for Institutional Effectiveness and Director of IR

• Muriel Lopez-Wagner

• Assistant Director• Tanner Carollo

• Institutional Effectiveness Associate• Joanna Oxendine

• Research Technicians• Allan Taing and Brandon Aragon

• Administrative Support Coordinator• Monica Villarruel

• Graduate Research Assistants• Eric Cazares, Claudia Alvarado , Lesley Quinonez, Keiry Borruel

What is SPSS?

• Statistical analysis software• Descriptive statistics and frequencies• T-Tests, ANOVA, correlations, etc.• Tabulated reports, graphs, and charts.

• Can also be used for data management

SPSS or Excel?

• Some benefits of using SPSS over Excel include:• Quick and easy access to descriptives

• Variety of charts and graphs

• Flexible pivot tables

• Easy to create subsets

• Easy value labeling

• User friendly with output that is easy to understand

Opening Excel Files

• Open SPSS• Opening Window

• Recent Files

• Open a dataset• File -> Open -> Data• File Type:

• SPSS Statistics (*.sav)• Excel (*.xls, *.xlsx, *.xlsm)

• Read Variable names from the first row of data

• Save File

Data View

• Data View• Each row is a different case• Each column is a different variable • Can drag and move variables (unlike Excel)• Variables can be used to group participants• (ex. “program”)

• Change to Variable View • Click Variable View tab• Double-click variable

Variable View: Describing your Data

• Edit Variables • Each row is a variable • Name

• Edit variable names• No special characters (spaces, $, /, etc.)• First character has to be a letter

• Type (String = alphanumeric, Numeric = numbers only)• Width• Change GPA to 2 decimal places• No decimals for ID

• Label: • Full Name from Excel

Variable View: Describing your Data (cont’d)• Value Labels

• Gives a label to simple values• Gender: 1 = Male, 2 = Female

• Missing Values • Force SPSS to exclude a value • EX: GPA = 99, Class Level missing value

• Align • Similar to Excel

• Measure• Nominal – Gender• Ordinal – Level• Scale – GPA

• Can copy/paste Labels, Values, and Missing• Change to Data View

• Click Data View tab• Double-click variable number

Search (case/variable)

• Data View• Click GPA -> Ctrl+F

• Variable View• Click Name/Label -> Ctrl+F

Frequencies and Descriptives

• Frequencies• Analyze -> Descriptive Statistics -> Frequencies • Class level, GPA, Gender, Program• Statistics and Charts buttons• Interpret (Frequency, Percent, Missing ClassLevel)

• Descriptives • Analyze -> Descriptive Statistics -> Descriptives• GPA, Gender• Interpret (N, Minimum, Maximum, Mean, Gender) • Remove Missing value from GPA• Right click variable -> Descriptives• Interpret (Different way to get information, different mean because of Missing)

Program Exercise

• Rename the “Program” variable so that it represents a program that is relevant to your area of expertise.• Enter a number for each case (values)• 1 = Participant, 2 = non-Participant• Add variable values

• Check the characteristics of the variable to make sure they are appropriate.

Select/Split Cases

• Data -> Split Files• Move program into the box, check ‘Compare groups’• Obtain the Descriptives of GPA

• Data -> Select Cases• If condition is satisfied

• Gender = 1 AND ClassLevel = ‘Freshman‘• Filter out unselected cases• Copy Selected cases to a new dataset• Delete unselected cases

• Descriptives of GPA

Crosstabs

• Analyze -> Descriptive Statistics -> Crosstabs• Select and drag row/column variables• Statistics• Cells - Percentages

• Create separate tables to analyze:• Class Level by Program Participants• Gender by Program Participants

Custom Tables

• Analyze -> Tables -> Custom Tables• Select and drag row variable(s)• Select and drag column variables(s)• Summary Statistics

• Adjust counts and percentages• Add Column N%• Add Table N%

• Categories and Tables• Totals• Category order

• Create separate tables to analyze:• Class Level by Program Participants• Gender by Program Participants

Computing New Variables/Recoding

• Transform -> Compute Variable • Target Variable – New Variable• Compute Honors if GPA >= 3.5

• Recode Missing Value• Tranform -> Recode into Same Var.• Old & New Values

• Old Value = System-missing• New Value = 0• Click Add

Custom Tables (Part II)

• Create a custom table to analyze Class Level by Honors and Gender• Versatility of customs tables allows

for multiple layers to be added• A more complex example - Analyze

Program and Class Level by Honors and Gender

Thank You!• Questions/comments?• Contact Us• AD-170• 909-537-5052• institutional_research@csusb.edu