Also hadn’t thought about decreasing the rank value based on the spammyness of sites a page is linking into. My guess on how to do it would be determining the spammyness of individual pages based on multiple page and site factors, then some type of reverse pagerank calcuation starting with the those bad scores, then overlaying that on top of the “good” pagerank calculation as a penalty. This is another thing which would be interesting to play around with in the Nutch algorithm.

#### Assume a small universe of four web pages: A, B, C and D. Links from a page to itself, or multiple outbound links from one single page to another single page, are ignored. PageRank is initialized to the same value for all pages. In the original form of PageRank, the sum of PageRank over all pages was the total number of pages on the web at that time, so each page in this example would have an initial value of 1. However, later versions of PageRank, and the remainder of this section, assume a probability distribution between 0 and 1. Hence the initial value for each page in this example is 0.25.

SEO techniques can be classified into two broad categories: techniques that search engine companies recommend as part of good design ("white hat"), and those techniques of which search engines do not approve ("black hat"). The search engines attempt to minimize the effect of the latter, among them spamdexing. Industry commentators have classified these methods, and the practitioners who employ them, as either white hat SEO, or black hat SEO.[49] White hats tend to produce results that last a long time, whereas black hats anticipate that their sites may eventually be banned either temporarily or permanently once the search engines discover what they are doing.[50]
“Google itself solely decides how much PageRank will flow to each and every link on a particular page. In general, the more links on a page, the less PageRank each link gets. Google might decide some links don’t deserve credit and give them no PageRank. The use of nofollow doesn’t ‘conserve’ PageRank for other links; it simply prevents those links from getting any PageRank that Google otherwise might have given them.”
###### Advertising with Google won't have any effect on your site's presence in our search results. Google never accepts money to include or rank sites in our search results, and it costs nothing to appear in our organic search results. Free resources such as Search Console, the official Webmaster Central blog, and our discussion forum can provide you with a great deal of information about how to optimize your site for organic search.

Another disadvantage is that even an individual or small group of people can harm image of an established brand. For instance Dopplegnager is a term that is used to disapprove an image about a certain brand that is spread by anti-brand activists, bloggers, and opinion leaders. The word Doppelganger is a combination of two German words Doppel (double) and Ganger (walker), thus it means double walker or as in English it is said alter ego. Generally brand creates images for itself to emotionally appeal to their customers. However some would disagree with this image and make alterations to this image and present in funny or cynical way, hence distorting the brand image, hence creating a Doppelganger image, blog or content (Rindfleisch, 2016).
It is increasingly advantageous for companies to use social media platforms to connect with their customers and create these dialogues and discussions. The potential reach of social media is indicated by the fact that in 2015, each month the Facebook app had more than 126 million average unique users and YouTube had over 97 million average unique users.[27]