Making Your Best GuesstimateThe Goal: Small Margin of ErrorChoosing a Confidence LevelFactoring in the Sample SizeCounting on Population VariabilityConfidence Interval for a Population MeanConfidence Interval for a Population ProportionConfidence Interval for the Difference of Two MeansConfidence Interval for the Difference of Two ProportionsInterpreting Confidence IntervalsSpotting Misleading Confidence Intervals