## Sunday, August 11, 2019

### Running Back Career Yardage Statistics and the NFL Draft.

A first look at descriptive statistics on career yards for first-round and second round running backs.

Question One:  How do average, median, the standard deviation, and the skew of first-choice and second-choice career yards differ?

Data source:  The data used for this problem can be found at

Information on career yards rushing for first-choice picks and second-choice picks are presented below.

 Descriptive Statistics Career Yards Running First-Choice Picks Second-Choice Picks Diff. % Diff. Average Career Yards 6506 5254 1252 10.6% Median Career Yards 4959 3952 1007 11.3% Standard Deviation of Career years 4978 4341 637 6.8% Skew of Career Yards 0.46 1.27 -1 -47.1%

Average career yards rushing and median career yards rushing are a bit more than 10% higher for first-choice picks than for second choice picks.    The standard deviation of first-choice picks is around 7% higher than the standard deviation of second-choice picks.   (I suspect that the slightly higher standard deviation for first-choice picks is largely attributable to a larger number of stellar first-round choices.)

Second round picks are more highly skewed than first round picks.   (The higher skew of second-round choices could be attributable to one outlier, Emmitt Smith. Also, the skew coefficient of 0.46 for first-choice picks suggests a relative modest positive skew.   The distribution for first-choice picks is not far from symmetric.)

My sense is that the difference in performance between first-choice end second choice running backs is relatively small but before I reach firm conclusions I need to look at a much wider range of performance statistics and compare to statistics from other positions.

#NFL Draft

#Statistics