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+# Normalized compression distance (NCD)
+
+
+## Calculation
+
+$$NCD_{Z}(x,y)={\frac {Z(xy)-\min\{Z(x),Z(y)\}}{\max\{Z(x),Z(y)\}}}.$$
+
+## Normal Compressor
+
+
+## Entropy
+
+
+## Use entropy in NCD
+
+
+## Let's practice!
+
+
+## Further reading