控制器是将视图上的行为(例如，按下Submit按钮)映射到模型上的操作(例如，检索用户详细信息)。
The Controller maps actions performed on the View (for example, pressing a Submit button) to operations on the Model (for example, retrieving user details).
对于第二种用户行为的检索，目前采取的办法是，根据包括个人基本资料信息，用户的历史行为，用户好友列表来推荐信息。
For the second, user-based analysis, a number of approaches have been taken, including ones based on profile information, user actions, and lists of the user's friends or contacts.
了解具体item和用户空间的规模，对于我们在决定是采用搜索item检索还是采用户行为分析检索有非常大的影响。
The dimensions of the particular item and user space are helpful in deciding whether to use an item-based or user-based approach.
应用推荐