Entering data, calculating descriptive

statistics and exploring your data using SPSS

Dr. Christine Gregory

November 2010

Open SPSS

Open, import and save data files

Defining variables

Summarising data

Descriptive statistics Descriptive statistics

Chart builder

What else can SPSS do?

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Opening SPSS 15.0Always open SPSS first, then open or type in data.

Choose ONE

Open a data file from

SPSS OR Excel

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Open existing data

Opening data in SPSS 15.0

Open existing data

from the File menu.

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Output File Shows output for ALL analysis run in SPSS

Keeps a log of all activity of open data files

Saved with the extension .spo

Everything done in SPSS is

shown here, in outline form.

A data file was saved as test.sav.

This was recorded in the log here.

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Saving your SPSS files Save in one of YOUR folders

Name file appropriately

Choose correct file extension

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Save as type:.sav for data files

.spo for output files

Importing data from Excel

The file MUST BE .xls NOT .xlsx

Variable names CAN be imported too

Must be in row 1 of the worksheet

Must begin with a letter

No spaces and no special characters (except _ )

Data will appear in SPSS data editor

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For Example. Importing data from Excel.

Variable names(Row 1)

Filename (.xls)

Sheet1 contains the dataset

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For Example. Importing data from Excel.Filename (.xls)

Select All Files

to see your .xls

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For Example. Importing data from Excel.

Tick here if

variable names

are in row 1.

Is this range correct?

If NOT

Enter correct range here

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Variable names(from Row 1)

View all data

For Example. Importing data from Excel.

View and define

variables

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SPSS Data Editor: Variable ViewView and define variables

Variable name

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SPSS Data Editor: Variable ViewView and define variables

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If numeric...

SPSS Data Editor: Variable ViewView and define variables

Describe the

variable

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SPSS Data Editor: Variable ViewView and define variables

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SPSS Data Editor: Variable ViewView and define variables

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SPSS Data Editor: Variable ViewView and define variables

Width of column

in data view

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SPSS Data Editor: Variable ViewView and define variables

Alignment of

data entries in

data view

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SPSS Data Editor: Variable ViewView and define variables

Classify

variable type

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SPSS Data Editor: Data ViewView, enter or change data entries

Menu Bar

Tool Bar

Choose your view:Choose your view:Numerical values

OR

Value labels

SUMMARISING DATASUMMARISING DATARepresenting data Diagrammatically & Numerically

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Levels of MeasurementData

CategoricalQualitative

ScaleQuantitative

Nominal(Unranked categories)

Ordinal(Ranked categories)

Discrete(Not possible to take

Continuous(Possible to take

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(Unranked categories)

Marital Status

Political Party

Eye Color

(Ranked categories)

Satisfaction level

Level of agreement

(Not possible to take

fractional values)

No. of cars

No. of students

(Possible to take

fractional values)

Height

Weight

In SPSS, data is either Nominal, Ordinal or Scale.

It is essential to classify data correctly in SPSS.- Incorrect classification will result in incorrect analyses.

Summarising Variables Graphically

Categorical

1 Variablee.g., Gender

2 Variablese.g., Satisfaction rating

Categorical Nominal or Ordinal

e.g., Gender e.g., Satisfaction rating

by Gender

Simple Bar Chart

OR

Pie Chart

Clustered Bar Chart

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Summarising Variables Graphically

Quantitative

1 Variablee.g., Gross Annual Income

Quantitative

by

Categorical

Quantitative Scale

2 or more related

Variablese.g., Holding breath, Categorical

e.g., Gross Annual Income by

Gender

Histogram

1-D Boxplot

Stem & Leaf Plot

Simple Boxplot

Population Pyramid

Bar Chart of Means

Clustered Boxplot

e.g., Holding breath,

drinking water, gargling,

spoon of sugar.Related: the same group of

participants tried all 4 methods to

get rid of hiccups.

Bar Chart

of Means

Summarising Variables Numerically

Categorical

1 Variablee.g., Gender

2 Variablese.g., Satisfaction rating

Categorical Nominal or Ordinal

e.g., Gender e.g., Satisfaction rating

by Gender

Frequency table

Mode and/or Medianuse Frequencies in SPSS

Contingency tableuse Crosstabs in SPSS

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Summarising Variables Numerically

Quantitative

1 Variablee.g., Gross Annual Income

Quantitative

by

Categorical

Quantitative Scale

Categoricale.g., Gross Annual Income by

Gender

Descriptive Statsuse Frequencies or

Descriptive Statistics in SPSS

Descriptive Statsuse Explore in SPSS

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DESCRIPTIVE STATISTICSDESCRIPTIVE STATISTICSDescribing and presenting data using SPSS

Download employ.sav from the ASK section on U-Link to carry out several of the

analysis shown in the remainder o the presentation.

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Descriptive Statistics Menu

Statistics

Charts Bar

Pie

Histogram

Frequency tablesFrequency tables

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Descriptive Statistics Menu

Limited statistics Mean, SE of Mean

Stdev, Variance

Range, Min, Max

Skewness, Kurtosis

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Descriptive Statistics Menu

Statistics

Plots Boxplots

Stem-and-leaf

Histogram

Normality plots Normality plots

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Descriptive Statistics Menu

Contingency table(Counts or %s)

Observed tallies

Expected tallies

Crosstab statistics Chi-square Chi-square

Correlations

Clustered bar charts

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Frequencies. Multiple scale and/or categorical variables.

ONLY

appropriate for

categorical variables

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Frequencies Output. Ethnic group and Job Satisfaction Scale 1

ONLY a frequency table was outputted.

Did not request statistics for these categorical variablesEthnic Group

36 51.4 51.4 51.418 25.7 25.7 77.114 20.0 20.0 97.1

2 2.9 2.9 100.070 100.0 100.0

White/EuropeanAsianWest IndianAfricanTotal

ValidFrequency Percent Valid Percent

CumulativePercent

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70 100.0 100.0

Job Satisfaction Scale - Item 1

7 10.0 10.3 10.322 31.4 32.4 42.624 34.3 35.3 77.913 18.6 19.1 97.1

2 2.9 2.9 100.068 97.1 100.0

2 2.970 100.0

Strongly DisagreeDisagreeUndecidedAgreeStrongly AgreeTotal

Valid

0MissingTotal

Frequency Percent Valid PercentCumulative

Percent

Total A

Total B

Percent = (Frequency)/(Total B)Valid Percent = (Frequency)/(Total A)

Descriptive statistics

Histogram with normal curve overlay.

Frequencies Output. Gross Annual Income

Statistics

Gross Annual Income682

7819.127800.00

6800a

997.947995897.7

.370

ValidMissing

N

MeanMedianModeStd. DeviationVarianceSkewness

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.291-.294.57446005900

105006925.007800.008675.00

Std. Error of SkewnessKurtosisStd. Error of KurtosisRangeMinimumMaximum

255075

Percentiles

Multiple modes exist. The smallest value is showna.

Messages appear at the bottom

Q1Q2

Q3

(Quartiles)

Descriptives. Analyse scale variables. Appropriate for scale variables ONLY.

Offers fewer statistics than Frequencies.

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Calculates the z-values for each

variable and saves as a new variable.

Descriptives Output. Gross annual income and Age last birthday

Standardised values

saved as variables:

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saved as variables:

Z-values for Gross

Annual Income and age

Explore. Examine each scale variable by each categorical variable.Add 1 or more

scale variables here

Add 1 or more

categorical

variables here

Output

Statistics ONLY

Plots ONLY

or Both

Outputs most

descriptives

offered under

Frequencies

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variables here

K-S test for normality for

each group within each

Factor variable for each

Dependent variable

Explore Output. Exam Performance by Gender

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Explore Output. Exa