Yates Correction Calculator

Formula

The formula to calculate the Yates correction for continuity (YC) is:

\[ YC = \left(\frac{(|O1 - E1| - 0.5)^2}{E1}\right) + \left(\frac{(|O2 - E2| - 0.5)^2}{E2}\right) \]

Where:

\( YC \) is the Yates correction for continuity
\( O1 \) is the observed frequency for cell 1
\( E1 \) is the expected frequency for cell 1
\( O2 \) is the observed frequency for cell 2
\( E2 \) is the expected frequency for cell 2
\( \left| \cdot \right| \) denotes the absolute value

Definitions

Yates Correction: A statistical procedure that corrects the chi-squared value for continuity, applied to a 2x2 contingency table when the sample size is small (usually less than 20).

Example

Let's say the observed frequency for cell 1 (O1) is 30, the expected frequency for cell 1 (E1) is 25, the observed frequency for cell 2 (O2) is 20, and the expected frequency for cell 2 (E2) is 15. Using the formula:

\[ YC = \left(\frac{(|30 - 25| - 0.5)^2}{25}\right) + \left(\frac{(|20 - 15| - 0.5)^2}{15}\right) \]

We get:

\[ YC \approx 2.16 \]

So, the Yates correction is approximately 2.16.