fix typos in fariness user guide

Author: ZebinYang

docs/_build/html/_sources/guides/testing/fairness.rst.txt

@@ -19,15 +19,15 @@ PIML supports various fairness metrics, as shown below. In specific, we use the
 .. math::
 
    \begin{align}     
-   AIR = \frac{(TP_{p}+FN_{p}) / n_{r}}{(TP_{r}+FN_{r}) / n_{p}}.
+   AIR = \frac{(TP_{p}+FP_{p}) / n_{r}}{(TP_{r}+FP_{r}) / n_{p}}.
    \end{align}
 
 - **Precision**: Positive predictive value disparity ratio.
 
 .. math::
 
    \begin{align}     
-   Precision Ratio = \frac{(TP_{p}) / (TP_{p}+FP_{p})}{(TP_{r}) / (FP_{r}+FN_{r})}.
+   Precision Ratio = \frac{(TP_{p}) / (TP_{p}+FP_{p})}{(TP_{r}) / (TP_{r}+FN_{r})}.
    \end{align}
 
 - **Recall**: True positive rate disparity ratio.

docs/_build/html/guides/testing/fairness.html

@@ -257,14 +257,14 @@ <h2><span class="section-number">6.7.1. </span>Fairness Metrics<a class="headerl
 </ul>
 <div class="math notranslate nohighlight">
 \[\begin{align}
-AIR = \frac{(TP_{p}+FN_{p}) / n_{r}}{(TP_{r}+FN_{r}) / n_{p}}.
+AIR = \frac{(TP_{p}+FP_{p}) / n_{r}}{(TP_{r}+FP_{r}) / n_{p}}.
 \end{align}\]</div>
 <ul class="simple">
 <li><p><strong>Precision</strong>: Positive predictive value disparity ratio.</p></li>
 </ul>
 <div class="math notranslate nohighlight">
 \[\begin{align}
-Precision Ratio = \frac{(TP_{p}) / (TP_{p}+FP_{p})}{(TP_{r}) / (FP_{r}+FN_{r})}.
+Precision Ratio = \frac{(TP_{p}) / (TP_{p}+FP_{p})}{(TP_{r}) / (TP_{r}+FP_{r})}.
 \end{align}\]</div>
 <ul class="simple">
 <li><p><strong>Recall</strong>: True positive rate disparity ratio.</p></li>