Chapter 5 Recode

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Chapter

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S P S S M A N U A L

Recoding SPSS Data

Often, you do not need the accuracy of ratio or interval level data.In this case, you can use the recode procedure to generate newvariables based upon survey data.

Suppose we ask survey respondents to write down their exact age. We may haveresponses from teenagers to octogarians. Although this information isimportant, it may be too cumbersome to work with in many statistical tests.You may decide to condense ratio data into interval or ordinal groups. This

example uses the age variable in the GSS91 (SPSSStudent Assistant)

Recoding is usually used to change higher-level data intolower-level data. Although you can move downwards withdata, you can never move upwards. Lower-level data can

never become higher-level data.

Performing a recode procedure.

First, print out the frequency table for the variable that you want to recode. Table 5.1represents the frequency table for the variable age. As you can see, we haverespondents from 19 years of age to 70.

Lets decide on the following recode of the variable:

Ages 19-29 will be recoded into a new variable and labeledyoung adultsAges 30-50 will be recoded into a new variable and labeled middle-age adults.Ages 51-70 will be recoded into a new variable and labeled older-adults.

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Performing a Recode Procedure

First, go to the Transform option on the toolbar, then choose Recode and then IntoDifferent Variables, see Figure 5.3. Then, click on the variable that you want to

recode.

Figure 5.3 Recode

Warning:If you select Into Same Variable youroriginal data will be permanently changed. Itis always safe to recode Into DifferentVariable.

Select the arrow and move the variable to the box under Numeric Variable. You canonly recode one variable at a time. In the Output Variable section, you need to create anew 8-digit variable name and label. As you can see in Figure 5.4, the new variable iscalled newage and the label is condensed age variable.

Fig. 5.4

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Old and New Values Recoded

Select Old and New Values, then Figure 5.5 appears, this is where you will perform theactual recoding procedure.

Figure 5.5 Recode Dialog Box

Under the old value you have a few options. They are as follows:

Value: select one value for recoding

Range: select a range of values for recoding

Range Lowest Through: select all the numbers below and including a specifiednumber

Range Though Highest: select all the numbers above and including a specifiednumber

All other values: used to declare missing values

Recall the following recodes:

19-29 will be recoded into newage and labeledyoung adults30-50 will be recoded into newage and labeled middle-age adults.51-70 will be recoded into newage and labeled older-adults.

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TABLE 5.1 AGE OF RESPONDENT (PARTIAL OUTPUT)Frequency Percent Valid

PercentCumulative Percent

Valid 18 3 .2 .2 .219 8 .5 .5 .7

20 18 1.2 1.2 1.921 37 2.5 2.5 4.422 35 2.3 2.3 6.723 28 1.9 1.9 8.624 23 1.5 1.5 10.225 27 1.8 1.8 12.026 33 2.2 2.2 14.227 28 1.9 1.9 16.028 33 2.2 2.2 18.229 27 1.8 1.8 20.030 35 2.3 2.3 22.431 35 2.3 2.3 24.732 44 2.9 2.9 27.7

33 38 2.5 2.5 30.234 35 2.3 2.3 32.535 55 3.7 3.7 36.236 35 2.3 2.3 38.537 32 2.1 2.1 40.738 36 2.4 2.4 43.139 35 2.3 2.3 45.440 36 2.4 2.4 47.841 36 2.4 2.4 50.242 30 2.0 2.0 52.243 33 2.2 2.2 54.444 30 2.0 2.0 56.445 22 1.5 1.5 57.946 12 .8 .8 58.747 27 1.8 1.8 60.548 29 1.9 1.9 62.549 22 1.5 1.5 63.950 20 1.3 1.3 65.351 15 1.0 1.0 66.352 20 1.3 1.3 67.653 14 .9 .9 68.554 18 1.2 1.2 69.755 16 1.1 1.1 70.856 12 .8 .8 71.657 17 1.1 1.1 72.758 18 1.2 1.2 73.959 15 1.0 1.0 74.9

60 16 1.1 1.1 76.061 19 1.3 1.3 77.362 16 1.1 1.1 78.463 18 1.2 1.2 79.664 15 1.0 1.0 80.665 18 1.2 1.2 81.866 13 .9 .9 82.667 18 1.2 1.2 83.8

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3 Step Recoding Process

Figure 5.6, 3 Step Recode

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Step 1: Place the values that you want to recode into the appropriate options underOld Value, see Figure 5.6.

Step 2: You need to place the corresponding new value in the box.

Step 3: Select add; the old value with its new value will appear in the box on the

right.I M P O R T A N T N O T E S

1. If I entered a number, such as 19, in the option Range Lowest Through, thatrange would include all possible ages up to and including 19.

2. If I entered a number, such as 71, in Range Though Highest, that range wouldinclude all possible ages beginning from 71.

3. After you are finished entering data, you should select all other valuesfrom theold value options, then select system-missingfrom new values. Any values thatyou failed to include in the recoding will be declared missing.

4. Figure 5.7 illustrates the completed recode.

5. When you are finished select Continue; you will beback to Figure 5.4.

6. You must select Change, then OK, see Figure5.8.

7. The new variable appears at the last column on theSPSS spreadsheet.

Fi ure 5.8 Chan e Ke

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Figure 5.8 illustrates how the variable newagecorresponds to its original variable, age.

But, youre not done

with the recode.

Figure 5.7, Completed Recode

You still need to create new value labels for the new variable. See Figure 5.9 and 5.10. Note that yousimply need to double-click on the variable label,new age in the data view screen. Once you are in

the variable view screen, simply left click in the box values.

Figure 5.8 The New Variable

Figures 5.9 and 5.10: AddingLabels to New Variable

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Source: GSS91 Survey

NEWAGE

older adultsmiddle age adultsyoung adults

Frequency

400

300

200

100

0

Source

Title

Age of Respondents700

600

500

The Final Graphical32


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Output

Begin to think about using charts to summarize your findings.

Dont forget, every chart needs a title and a source (add these features inthe Chart Editor).

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Chapter 5 Recode

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