ADD:

AIC statistic added

etc/tools/statistics.py

@@ -0,0 +1,18 @@
+import numpy as np
+
+
+def aic_statistic(dist, data, axis):
+    """
+    AIC-based goodness-of-fit statistic.
+
+    AIC = 2k - 2ln(L)
+
+    Lower AIC indicates better fit, but since goodness_of_fit()
+    treats larger statistic values as worse fit, AIC works directly.
+    """
+
+    k = len(dist.args)
+    log_likelihood = np.sum(dist.logpdf(data), axis=axis)
+    aic = 2 * k - 2 * log_likelihood
+
+    return aic