Often when websites are created their owners want people to come to their sites and never leave. This mentality leads to website owners often leaving outbound links off their pages. This type of strategy can seriously hinder your rankings in major search engines.
Google's algorithm is heavily based on the linking structure of the web. It is an accepted fact that inbound links add value to a site. Why is it then left to the wayside that a lack of outbound links could be detrimental?
According to e factory:
Since PageRank is based on the linking structure of the whole web, it is inescapable that if the inbound links of a page influence its PageRank, its outbound links do also have some impact.
So how can we build quality outbound links to benefit our needs?
First do some research as to the sites most relevant for your main keywords. Link to these sites using in-text links with keyword rich anchors. As a personal preference I usually assign the links to open in a new window to keep my visitors from leaving my site.
When building outbound links I like to put 1 link out for every 20 pages of content. You could also build your outbound links according your inbound link count.