CoreLogic has re-crunched housing sales price data and come up with a somewhat rosier picture of the market when sales of foreclosed homes are left out. It's not a small difference.

Year-over-year prices for all home sales fell by 3.9 percent in October. However, CoreLogic reported, the change is a negative 0.5 percent when considering only sales by owners. The same effect shows for September, with a 3.8 percent price decline overall but only 2.1 percent for non-distressed sales.

The explanation is not location but rather motivation, The Wall Street Journal's Nick Timiraos said in reporting on the new findings.

"Unlike traditional owners, banks are often faster to cut prices in order to unload properties quickly – or what are called 'distressed' sales. The upshot is that, the more homes being sold by lenders in any given month, the faster prices tend to fall," Timiraos said.

He also noted that individuals are less inclined to offer or buy homes in winter months, so sales of foreclosures make up a bigger piece of the monthly numbers and add to the distress effect.