gini系数计算

1 files changed, 26 insertions, 0 deletions

diff --git a/stats/gini_index.py b/stats/gini_index.py
new file mode 100644
index 0000000..8821429
--- /dev/null
+++ b/stats/gini_index.py
@@ -0,0 +1,26 @@
+import numpy as np
+
+
+def gini(x):
+    mean = np.mean(x)
+    mad = np.mean(np.abs(x - mean))
+    rmad = mad/mean
+    return rmad/2
+
+
+if __name__ == '__main__':
+
+    x = np.asarray([2, 2, 4, 4])
+    print(gini(x))
+    x = np.asarray([1, 1, 6, 4])
+    print(gini(x))
+
+    x = np.random.rand(500)
+    print(gini(x))
+    x = np.random.rand(500)+1
+    print(gini(x))
+    x = np.random.rand(500)+10
+    print(gini(x))
+    x = np.random.rand(500)+100
+    print(gini(x))
+