There is a popular and useful WordPress plugin called kk Star Ratings that allow visitors to the website leave feedback in form of star rating. The usage of this plugin bring some benefit to the webmaster. First of all, the click rate in search result may be slightly higher because Google (perhaps other searach engines too) display star rating icons which encourage people to click. The second benefit is the feedback the website owner gets from visitors. If the rating is low, it is clearly a sign that there is something wrong with the post. If this happens, the editor should re-write the post and make it more valuable.
Tampering with these ratings is not a great idea and my intention is not to write instructions how to cheat 🙂 It is more how to protect your website against fake ratings posted by a hater or a competitor.
I have recently had exactly such a case. The ratings of one of articles on of my site smartpolak.co.uk were suddenly suspiciously low. I have checked Google Analytics and it turned out that while usually there are around 15-20 visits per day, there are some days with more 200 visits. During these days the ratings went really low. I know that the percentage of visitors that actually leave these rating is very low, probably around 1% if not less, so when suddenly I got 200 ratings in one day, I knew that something was wrong 😮