Asosiasi dan disosiasi

Analisis Market Basket dengan Python

Isaiah Hull

Visiting Associate Professor of Finance, BI Norwegian Business School

Memasangkan ebook dengan disosiasi

Gambar mini sampul buku The Hobbit.

Gambar mini sampul buku The Great Gatsby.

Gambar mini sampul buku Pride and Prejudice.

Gambar mini sampul buku The Catcher in the Rye.

¹ Gambar diambil dari goodreads.com.

Pengenalan metrik Zhang

Diperkenalkan oleh Zhang (2000)
- Bernilai antara -1 dan +1
- +1 menunjukkan asosiasi sempurna
- -1 menunjukkan disosiasi sempurna
Komprehensif dan mudah ditafsirkan
Dibangun dari support

¹ Zhang, T. (2000). Association Rules. Proceedings of the 4th Pacific-Asia conference, PADKK, hlm. 245-256. Kyoto, Jepang.

Mendefinisikan metrik Zhang

$$Zhang(A \rightarrow B) = $$ $$\frac{Confidence(A \rightarrow B) - Confidence(\bar{A} \rightarrow B)}{Max[Confidence(A \rightarrow B), Confidence(\bar{A} \rightarrow B)]}$$ $$Confidence = \frac{Support(A \& B)}{Support(A)}$$

Menyusun metrik Zhang dengan support

$$Zhang(A \rightarrow B) = $$ $$\frac{Support(A \& B) - Support(A) Support(B)}{ Max[Support(AB) (1-Support(A)), Support(A)(Support(B)-Support(AB))]}$$

Menghitung metrik Zhang

# Compute the support of each book
supportH = hobbit.mean()
supportP = pride.mean()

# Compute the support of both books
supportHP = np.logical_and(hobbit, pride).mean()

Menghitung metrik Zhang

# Compute the numerator
num = supportHP - supportH*supportP

# Compute the denominator
denom = max(supportHP*(1-supportH), supportH*(supportP-supportHP))

# Compute Zhang's metric
zhang = num / denom
print(zhang)

0.08903

Ayo berlatih!

Analisis Market Basket dengan Python