There has been some discussion around whether fluctuations in personal robbery in London could account for, or predict, changes in the number of teenagers that are fatally wounded in London.
The basis for this view is that:
The important thing about having a hypothesis or view is to test it against the available data.
Combined Charts of London Teenage Murders and Robbery volumes per month – April 2007 to March 2011
On first view it does look like something is going on and there is some alignment in the general trend in each of these two charts. However a correlational test reveals a very poor linear relationship (r=0.234) between the two sets of data.
It could be argued that any relationship is unlikely to be linear so further work is clearly needed to either reject or accept the link between robbery and teenage murder.