Validitas dan Reliabilitas menggunakan SPSS

Introduction

This tutorial provides a comprehensive guide on how to assess validity and reliability of questionnaires using SPSS. Understanding these concepts is crucial for researchers to ensure their data collection tools are effective and trustworthy. This guide will walk you through the Pearson Product Moment validity test and the Cronbach Alpha reliability test, both essential for evaluating your research instruments.

Step 1: Conduct Validity Test Using Pearson Product Moment

Validity determines whether your questionnaire accurately measures what it is intended to measure. Follow these steps to perform the validity test:

1. Prepare Your Data:

   • Ensure your questionnaire responses are entered into SPSS correctly.

2. Run the Pearson Correlation Test:

   • Navigate to Analyze > Correlate > Bivariate.
   • Select the variables you want to test and move them to the Variables box.
   • Make sure to check the Pearson box under correlation coefficients.
   • Click OK to run the analysis.

3. Interpret the Results:

   • Compare the calculated correlation coefficient (r hitung) with the critical value from the r table.
   • For N=60 at a 5% significance level, the critical value (r tabel) is 0.254.
     • If r hitung > 0.254, the item is valid.
     • If r hitung < 0.254, the item is not valid.
   • Additionally, check the significance value (Sig.):
     • If Sig. < 0.05, the item is valid.
     • If Sig. > 0.05, the item is not valid.

Step 2: Conduct Reliability Test Using Cronbach Alpha

Reliability assesses whether your questionnaire consistently measures the same construct across multiple iterations. Follow these steps to perform the reliability test:

1. Open Your Data in SPSS:

   • Ensure your questionnaire items are organized in SPSS.

2. Run the Cronbach Alpha Test:

   • Go to Analyze > Scale > Reliability Analysis.
   • Select the items you want to test and move them to the Items box.
   • In the Model drop-down menu, select Alpha.
   • Click OK to execute the analysis.

3. Interpret the Results:

   • Check the Cronbach Alpha value:
     • If Cronbach Alpha > 0.6, the questionnaire is considered reliable.
     • If Cronbach Alpha < 0.6, the questionnaire is not reliable.

Step 3: Download R Table for Reference

To support your validity tests, you may want to download the r table used for comparison. You can find it here:

• Download R Table

Conclusion

In this tutorial, you learned how to conduct validity and reliability tests using SPSS. By following the steps for Pearson Product Moment and Cronbach Alpha, you can ensure your questionnaire is both valid and reliable, enhancing the quality of your research findings. For further learning, consider exploring additional analyses such as linearity tests or descriptive statistics comparisons using SPSS or Excel.