2022 Introduction to Statistics in Research Mitchell 2nd ed

I N T R O T O R E S E A R C H : D A T A V I S U A L I Z A T I O N & C O M M O N S T A T T E S T S

Table 24: Recoded questions shown in SPSS Version 27

Internal Consistency Now that we have our questions recoded, we need to conduct a reliability analysis which for a questionnaire is called “internal consistency.” According to Adam & McGuire (2022), “internal consistency is used to assess the reliability of scales or subscales” (p. 94). In the global warming survey we want participants to respond consistently to multiple items on a scale consistently. Cronbach’s alpha α: In order to measure internal consistency, we use Cronbach’s alpha α . This test is “ used to assess the internal consistency of a scale by computing the intercorrelations among responses to scale items; values of .70 or higher are interpreted as acceptable internal consistency ” (Ibid, 2022, p. 94). Again, we can turn to our statistical packages to conduct this test for intern al consistency of our questionnaire. That’s one reason studies will set up a pilot study first so the researcher has a chance to correct internal consistency issues. Internal consistency can be measured both by Cronbach’s alpha α and by split -half reliability. According to Adam & McGuire, split- half reliability is a “correlation between the responses to half the items on scale to the other half (usually even-numbered items correlated with odd- number items” (2022, p. 94).

Either test has a goal of .70 or higher . Now let’s look at the steps to calculate Cronbach’s alpha α in SPSS.

Cronbach’s alpha α in SPSS As you get ready to run this test, remember to use the recoded values . 1) On the menu bar, click Analyze >, Scale > Reliability Analysis

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