Bias trackers are Gail Howard's eight short term lotto trend charts. These charts help you look at biases that occur for lotto numbers. The lotto charts are Odd-Even Bias Tracker, High-Low Bias Tracker, Sum Chart Bias Tracker, Number Groups Bias Tracker, Hot-Cold Bias Tracker, Skips Due Bias Tracker, Last Digit Bias Tracker, and the Percentage System. You can use these charts in Advantage Gold or Lottery Master Guide to help you pick lotto numbers.