CARA MUDAH UJI RELIABILITAS MENGGUNAKAN K-R. 20

Introduction

This tutorial provides a straightforward guide on testing reliability using the K-R. 20 method. Reliability testing is crucial in research and assessments to ensure the consistency of measurements. This guide will help you understand the steps needed to perform this test effectively.

Step 1: Gather Your Data

• Collect Your Dataset: Ensure you have a dataset that is appropriate for reliability testing. This dataset should include responses from a sample population.
• Format the Data: Make sure the data is clean and organized, typically in a spreadsheet. Each row should represent a different respondent, and each column should represent a different item or question.

Step 2: Calculate the Item Variance

• Identify Items: Determine the items (questions) in your dataset that you want to test for reliability.
• Compute Variance: For each item, calculate the variance. You can use statistical software or spreadsheet functions like VAR.P in Excel for this calculation.

Step 3: Calculate the Total Variance

• Sum Item Scores: For each respondent, sum their scores across all items to get a total score.
• Calculate Total Variance: Use the total scores to calculate the total variance using the same method as in Step 2.

Step 4: Apply the K-R. 20 Formula

• Understand the Formula: The K-R. 20 formula is:

  [ K-R.20 = \frac{k}{k-1} \left(1 - \frac{\sum s_i^2}{s_t^2}\right) ]

  Where:

  • ( k ) is the number of items,
  • ( s_i^2 ) is the variance of each item,
  • ( s_t^2 ) is the total variance.

• Plug in Your Values: Insert the calculated variances into the formula to compute the K-R. 20 coefficient.

Step 5: Interpret the Results

• Understand Reliability Coefficients:

  • A K-R. 20 value closer to 1 indicates higher reliability.
  • Values above 0.7 are generally considered acceptable.

• Evaluate and Report: Based on your K-R. 20 result, assess whether your items have adequate reliability. Report these findings in your research or analysis.

Conclusion

You've now learned how to test reliability using the K-R. 20 method. By following these steps, you can ensure your measurements are consistent and credible. For further analysis, consider exploring other reliability tests like Cronbach's Alpha, which can provide additional insights.