Formatting tables

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Transcript Formatting tables

GAP Toolkit 5
Training in basic drug abuse data management
and analysis
Training session 10
Table manners
Objectives
• Define the common terminology used to evaluate
survey data
• Establish the information that should be reported
with the data, whether the data take the form of a
table, a graph or numerical summaries
• Introduce the Output Viewer in SPSS
• Describe formatting charts and tables
Conflicting aims
• A table has two purposes:
– To put across a point
– To allow the reader to verify our claims with reference to the
data
• “These aims are not always the same and getting the
balance right is as much an art as a science.”
(C. Marsh, Exploring Data: An Introduction to Data Analysis for
Social Scientists (Cambridge, Polity Press, 1988)).
Survey terminology
• Reliability
• Validity:
– Internal
– External
Reliability
• A tool of measurement displays reliability if it records
the same result in repeated applications under identical
conditions
• For example:
– I weigh myself on my bathroom scales on Monday and weigh
100 kg
– I weigh myself on my bathroom scales on Tuesday and weigh
72 kg
– This would be nice, but is unlikely: the scales are probably
unreliable
Validity
• Validity takes various meanings in survey design
• Internal validity is the ability of the measure (the
question or observation) to adequately represent the
underlying concept of interest
External validity
• External validity refers to the ability to abstract
generalizations from the results:
– Are the data from a sample?
– If “yes”, is that sample a reasonable representation of the
population?
– If so, can the results be generalized to the population?
Table design
• Clarity:
– Structure
– Message
• Completeness
Titles
• Who/What?
• When?
• Where?
Source
• It is essential that the source of the data is presented
regardless of what form the statistics take
• The source of the data helps establish the authority of
the data
Variables
• Definitions
• Units
Percentages
• If a variable is measured in percentages, be certain it is
clear what it is a percentage of:
– Rows
– Columns
– Totals
• Ensure that the original numbers can be calculated by
reporting the sample size (the size of the denominator
in the calculation of the percentage)
Method
• Sample statistics are frequently used to make general
statements about the population
• If the statistics are drawn from a sample, state the
method of sampling
• The method determines the external validity of the
results
Missing data
• Always report the number of missing observations in
your data set
• A large amount of missing data brings into question the
external validity of a survey:
– Those who agreed to answer and those who refused may
well have different characteristics
Precision
• Avoid reporting data to unjustifiable levels of precision
• Round results to the level of precision of the original
data
Output Viewer
• The third main window in SPSS
• Used to edit and format the results of any statistical
analysis
• Generates output files with the suffix .spo
Exercise: Session 8: Output
• Retrieve the output file “Session 8 freq.spo” saved in
session 8
Output
Table of
contents
Left-hand panel
• Use the left-hand panel to manage the output
• Clicking on a heading selects that part of the output
• Clicking on the – sign to the left of a heading hides or
collapses the output
• Clicking on the + to the left of a heading displays or
expands the output
Right-hand panel
• Select a single piece of output by pointing and clicking
once
• Select multiple pieces of output by holding down the Ctrl
key while clicking more than once
• Format output by pointing and double-clicking
Copying tables to Word
•
•
•
•
Select the output in the left-hand panel or in the Viewer
Edit/Copy
Move to Word
Edit/Paste Special:
– Formatted Text
– Unformatted Text
– Picture
Copying charts to Word
•
•
•
•
Select the output in the left-hand panel or in the Viewer
Edit/Copy
Move to Word
Edit/Paste
Exercise: copying to Word
• Copy the frequency table for Education to a Word
document as:
– Formatted text
– Unformatted text
– Picture
• Copy the bar chart of Education to the same Word
document as a picture
Formatting tables
• Double click to enter formatting mode
• A new border appears around the output with short
diagonal lines at a 45-degree angle
• The menu bar now contains formatting options
Editing the table
• Edit any component of the table by double-clicking that
particular part of the table
• A box will appear in which the table can be edited
Race of clients: treatment centres in the Cape region of South Africa
January-June 2001
Frequency
Valid
Cumulative Percent
722
46.0
52.8
52.8
White
520
33.1
38.0
90.8
African
109
6.9
8.0
98.8
17
1.1
1.2
100.0
1368
87.1
100.0
203
12.9
1571
100.0
Total
Total
Valid Percent
Coloured
Asian
Missing
Percent
System
Insert
• Insert/Title
• Insert/Caption
• Insert/Footnote
Caption text box
Type required
caption here
Race of clients: treatment centres in the Cape region of South Africa
January-June 2001
Frequency
Valid
Cumulative Percent
722
46.0
52.8
52.8
White
520
33.1
38.0
90.8
African
109
6.9
8.0
98.8
17
1.1
1.2
100.0
1368
87.1
100.0
203
12.9
1571
100.0
Total
Total
Valid Percent
Coloured
Asian
Missing
Percent
System
Source: The data were collected from the treatment centres as part of the South African
Drug Information System.
Race of clients: treatment centres in the Cape region of South Africa
January-June 2001
Frequency
Valid
Cumulative Percent
722
46.0
52.8
52.8
White
520
33.1
38.0
90.8
African
109
6.9
8.0
98.8
17
1.1
1.2
100.0
1368
87.1
100.0
203
12.9
1571
100.0
Total
Total
Valid Percent
Coloured
Asian
Missing
Percent
a
System
Source: The data were collected from the treatment centres as part of the South African
Drug Information System.
a
Note that the small number of Asian clients raises issues of the generalizability of
the results pertaining to the Asian community.
Format
• Format/Table Properties
• Format/TableLooks
TableLooks
Race of clients: treatment centres in the Cape region of South Africa
January-June 2001
Frequency
Valid
Total
Valid Percent
Cumulative Percent
Coloured
722
46.0
52.8
52.8
White
520
33.1
38.0
90.8
African
109
6.9
8.0
98.8
Asiana
17
1.1
1.2
100.0
1368
87.1
100.0
203
12.9
1571
100.0
Total
Missing
Percent
System
Source: The data were collected from the treatment centres as part of the South African
Drug Information System.
a
Note that the small number of Asian clients raises issues of the generalizability of
the results pertaining to the Asian community.
Formatting charts
• Double-click a chart in the Output Viewer to open the
chart in the Chart Editor
• To edit or format the chart:
– Point at the part to be edited and double-click
OR
– Use the menu bar options
Exercise
• Using the file ‘Session 8 freq.spo’, edit the frequency
table and the bar chart for the variable Education to
reflect the principles discussed here
• Copy the edited frequency table and bar chart to a
Word document
Summary
• Principles:
– Subject of the data
(who/what?)
– Time period (when?)
– Area covered (where?)
– Variables:
• Definitions
• Units of measurement
– Method
• Saving Output:
– To file
– To a word-processor
• Tables
• Charts