When does short term stock strength extrapolate?

After careful analysis of the stock scan that looks for stocks with 3 days strength, more than half the stocks did not continue to do well in the short term. Since this scan is not meant as a scan for stocks to short sell, I had to re-examine the strategy.

The stocks that did well typically were recovering from a long period of devaluation. I added the criteria of a stock must be devalued over one month. The results were much better. This weekend's scan reveals:
KOMG, KOMAG INC (Google Yahoo Earnings Chart) 

The scan for 3 days of weakness followed by strength for the top half year growth stocks reveals:
CTIC, CELL THERAPEUTICS (Google Yahoo Earnings Chart) 
FDP, FRESH DEL MONTE P (Google Yahoo Earnings Chart) 

Not a bad selection...