• 沒有找到結果。

結論與未來展望

5.1 研究總結

在大多的情況下,資料類別及個數資訊在巨量資料問題下是未知的,而且也 無法透過專家經驗或實驗方式得知,因此無母數方法比固定參數的機器學習方法更 適合處理巨量資料。在實驗中,當資料量大時,我們提出的 Online CRP 不僅在分 類的效能上能夠達到監督式學習方法的標準,且在執行時間也比很多方法快速,驗 證本方法可準確並有效率的處理巨量資料問題。

5.2 未來展望

目前有 online 概念的 graphical model 研究,大部分只研究主題隨時間的演變,

較少探討使用標記資料來對模型的參數估計做調整的問題,因此未來可能可以利用 標記資料來探討其他 graphical model 和 Online Learning 的結合。

標記資料引入 graphical model 在此論文是使用一個隨機變數來表示標記資料,

未來的方向可以在 graphical model 中多設計一些隨機變數,例如加入 Universum 的資料等等,來影響整個系統的機率參數之估計。

本論文提出的方法具動態的自我成長和自我訓練功能,並不排斥於對新領域的 即時學習與擴展,因此很適合整合成一套實務上的應用系統,也是未來可以考慮的 發展方向。此外,針對新訓量資料引進,參數一直在變動,可以由圖 4.5-1 中看出,

新訓練資料加進來,參數變動並不一定造成效能提升,因此未來可以考慮借用 Average Perceptron 之概念,將全部或部分參數紀錄下來,並使用所有參數預測 之平均的機率值來當預測值。

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