It is because some search engines will see them as duplicate content and decrease your page rank. 这是因为一些搜索引擎会看到他们视为重复的内容,降低您的网页排名。
They can use their Google page rank to make sure their content floats to the top, he says. 他表示:它们可以利用自己的谷歌网页排名来确保其内容上升到顶部。
Research on XML-based Index and Page Rank(PR) Technology in Vertical Search 垂直搜索中XML索引及页面排序技术研究
Companies with a high page rank are in a strong position to move into new markets. 网页排名靠前的公司在进军新市场方面处于有利地位。
If you are paying for link submission in a directory, make sure that the page rank of the directory is high and it has good traffic. 如果您在支付环节提交的目录,请确保该目录的网页排名较高,具有良好的交通。