Add description to card metadata (#1)

- Add description to card metadata (6aafb78bc556e5ba5fd7a2f05a82e3f63f054bb7)

README.md

@@ -1,6 +1,6 @@
 ---
 title: Accuracy
-emoji: 🤗 
+emoji: 🤗
 colorFrom: blue
 colorTo: red
 sdk: gradio
@@ -8,10 +8,22 @@ sdk_version: 3.0.2
 app_file: app.py
 pinned: false
 tags:
-- evaluate
-- metric
----
+  - evaluate
+  - metric
+description: >-
+  Accuracy is the proportion of correct predictions among the total number of
+  cases processed. It can be computed with:
+
+  Accuracy = (TP + TN) / (TP + TN + FP + FN)
+   Where:
+  TP: True positive
+
+  TN: True negative
 
+  FP: False positive
+
+  FN: False negative
+---
 # Metric Card for Accuracy