Identifying the Association Rules between Clinicopathologic Factors and Higher Survival Performance in Operation-Centric Oral Cancer Patients Using the Apriori Algorithm

Algorithm 1

Pseudocode of the Apriori algorithm.

01: 𝐿₁ = {𝑙₁,…,𝑙_𝑛∣∀𝑙∈largeitemsets} //see Section 2.2.1

02: set k = 2

03: while (𝐿_𝑘−1≠∅)

04:  𝐶_𝑘 = apriori-gen (𝐿_𝑘−1) = {𝑐₁,…,𝑐_𝑝 ∣ 𝑐∈ candidate 𝑘-itemsets}

  // see Section 2.2.2

05: if (𝐶_𝑘 = ∅)

06: return

07: end if

08: for (all t ∈𝐷)

09: 𝐶_𝑡 = subset (𝐶_𝑘, t) // see Section 2.2.3

10: for (all 𝑐∈𝐶_𝑡)

11:   c.count++

12: end for

13: end for

14:  𝐿_𝑘 = {𝑐∈𝐶_𝑘∣𝑐.𝑐𝑜𝑢𝑛𝑡≥minsup}

15:  k++

16: end while