基于K-means的改进协同过滤算法

来源 :天津科技大学学报 | 被引量 : 0次 | 上传用户:klyx808
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协同过滤算法在推荐系统中得到了广泛的应用,但是随着数据的不断增长,用户相似度低、推荐准确性不高等问题也逐渐显现.针对上述问题,提出一种基于K-means的改进协同过滤算法.首先,通过K-means聚类算法将相似的用户进行聚类,在聚类过程中,利用欧几里得公式计算数据之间的距离,该算法得到聚类效果最好的簇数K;其次,将K值作为二分K-means算法的输入,通过该聚类算法得到最终的聚类结果;再次,通过改进之后的相似度公式得到目标用户的邻居用户集合;最后,通过预测评分公式预测项目的分值.实验表明,该算法在准确率、召回率以及F1指标上都有一定程度的提高.
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