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Story Name: Estimating the Speed of Light
Story Topics: Science
Datafile Name: Speed of Light
Methods: Confidence interval , Distribution , Histogram , Outlier
Abstract: Simon Newcomb measured the time required for light to travel from his laboratory on the Potomac River to a mirror at the base of the Washington Monument and back, a total distance of about 7400 meters. These measurements were used to estimate the speed of light.

A histogram or dotplot of these data shows a normal distribution except for two outliers. Newcomb ultimately dropped the lowest outlier, -44, from his analysis. The average measurement may be used to estimate the speed of light, and various confidence intervals for the mean may be calculated. You may wish to calculate means and confidence intervals both including and excluding the outliers.

Image: Histogram of Newton's measurements