Journal Impact Factor
It’s become very common nowadays that many institutors required academician to publish their papers into certain Journal that has impact factor. The impact factor give the notions that the journasl has more prestigious than not have ones. However there are negative impact as well.
The requirement for impact factor might give negative impact since authors will make “bad collaboration” with each author for “internal cross citation” or “cross citation between colleagues” or “required citation from the publishers or professors”
Please find the detail on http://www.google.com/search?q=self+citation
I found some sources that discuss about Jurnal Impact Factors that very valuable to us
2. http://www.sciencemag.org/content/340/6134/787.full