One relatively straightforward measure is the '' Web Impact Factor '' ( WIF ) defined by Ingwersen in 1998 as the number of total link pages , divided by the number of web pages published in the site that are accessible to the crawler .
One relatively straightforward measure is the '' Web Impact Factor '' ( WIF ) introduced by Ingwersen ( 1998 ) . 
 The WIF measure may be defined as the number of web pages in a web site receiving links from other web sites , divided by the number of web pages published in the site that are accessible to the crawler .