• 沒有找到結果。

結論與討論

從以上實驗中我們確實可以觀察出 CARC 演算法比 CBA 演算法有更好的準 確度,在實驗一中可以發現當 MinSup 的值超過 5%時,CBA 的準確度明顯降低,

那是因為當 Support 值設得太高時,所產生的關聯規則變少,許多重要的規則未 被產生,因此造成要對測試資料進行分類的判斷時,會導致分類錯誤的產生。

除了因為 Support 值設定太高造成產生之規則過少,預設類別的選擇也是影 響分類錯誤的重要因素之ㄧ。從實驗一中可得知 CARC 並不因為 MinSup 值過大 而導致準確度的降低,依然維持著相當高的準確率。從實驗二和實驗三中亦可看 出 CARC 精確度比 CBA 高或是不相上下。在實驗參數設定的部份,鑒於 MinSup 過高會產生太多無意義的規則,設定太低又會有許多規則無法被產生,因此,在 實驗中將 MinSup 值設定在 0.01%和 30%之間。另外,在實驗四中也可發現當 k 最小設定為 5 時,準確率大致上是比較低的,所以,可知預設類別的選擇也是影 響準確度因素之ㄧ。

本論文所提出之 CARC 演算法經實驗結果證明,確實能達到良好的正確率,

找出正確的規則,不但可以找出 Support 高的規則,亦可以找出 Support 低卻緊 密性高的規則,並能提供好的預設類別演算法,將測試資料分類正確,提高演算 法的準確率。CARC 演算法在產生規則的部份是以 Condenseness 為過濾規則的 指標,其中 Condenseness 的求值公式又與 Lift 值的大小有關聯,因此,在未來 研究上可以針對此部分加以探討,因為除了 Lift 這種衡量規則間關係的衡量指 標,尚有其他衡量指標(如第 3.1 節中所介紹的各種規則衡量標準)可以加以整合 利用,以達到較高準確率的分類結果。

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