1. What is Yates' Continuity Correction?

Yates' continuity correction is an adjustment made to the Pearson chi-square test for 2×2 contingency tables. It compensates for the overestimation of the chi-square value that occurs with small sample sizes.

2. How Does the Calculator Work?

The calculator uses the Yates' corrected chi-square formula:

Where:

• \( O \) — Observed frequency
• \( E \) — Expected frequency
• 0.5 — Yates' correction factor

Explanation: The correction subtracts 0.5 from the absolute difference between observed and expected frequencies before squaring, reducing the chi-square value.

3. When to Use Yates' Correction

Details: Use Yates' correction when you have a 2×2 contingency table with small sample sizes (expected frequencies < 5 in any cell). For larger samples, the standard chi-square test is preferred.

4. Using the Calculator

Tips: Enter the four observed values (a, b, c, d) from your 2×2 contingency table. All values must be non-negative integers.

5. Frequently Asked Questions (FAQ)

Q1: When should I use Yates' correction?
A: Use it for 2×2 tables with small sample sizes (expected frequencies < 5) to reduce Type I error.

Q2: What are the limitations of Yates' correction?
A: It may be overly conservative, increasing Type II error (false negatives). Some recommend Fisher's exact test instead for small samples.

Q3: How do I interpret the chi-square value?
A: Compare it to critical values from the chi-square distribution table with 1 degree of freedom to determine statistical significance.

Q4: What's the difference between this and Pearson's chi-square?
A: Pearson's chi-square doesn't include the -0.5 correction factor, making it more likely to find significant results with small samples.

Q5: Can I use this for larger contingency tables?
A: No, Yates' correction is only for 2×2 tables. For larger tables, use standard chi-square or other appropriate tests.