Ever since I belatedly took the MPRE last weekend, I’ve been wondering what, exactly, my score will mean.  The MPRE website unhelpfully says that the score is scaled between 50 and 150, with the mean (the average) at 100.  What exactly does this mean for someone who needs an 85 for their bar-exam state?  What percentile do I need to attain in order to pass?  More importantly, where on the bell curve will my score put me compared to other test-takers around the country?

I did some digging and found out how to compute an MPRE score percentile in comparison to test-takers nationwide.  According to the Legal Profession Blog, the mean score on the MPRE is actually a bit lower than what ACT, the company that produces the MPRE for the National Council of Bar Examiners, tells us it is.  In reality, the mean is approximately 98.33.  Their other published data shows that the standard deviation for test-takers is 19.72.  Thus, if you know what your MPRE score is, you can compute your percentile position using this information.  I spelled it out for those of us who don’t remember taking college statistics:

1. Compute Your Z-Score.  Use this formula to compute your z-score, where “X” is your individual MPRE score:

   Z = (X - 98.33) / 19.72

 

2. Use Your Z-Score to Compute Your Percentile.  Instead of dealing with more algebra to determine how your z-score translates into your position on the bell curve, you can go to the Measuring Usability website and use the Z-Score to Percentile Calculator.  Select the ”One-Sided” button and input your z-score into the text box.  Don’t forget to use a negative sign if your z-score was negative.  The calculator will produce two numbers for you, with the “Percent of Area” number being your percentile score.

That’s all there is to it!  After playing with this for a while, you will notice that many states require very little from the people taking the MPRE.  Even states that are on the high end of the country and require bar applicants to get an 85 or better on the MPRE are really only asking you to land somewhere in the 24th percentile or better.  In other words, you only need to do better than about 1 out of 4 people who took the test.  This means that for those of you who got around a 130, you are in the top 5 or 10 percent of the country.  Sorta makes you wonder why you studied so hard, huh?  Anyway, check out this quick Wikipedia entry on standardized scoring for more information on how this works.

Now why can’t ACT simply give us a chart so we don’t have to go through this hassle?  Nobody seems to know for sure, but it may have something to do with licensing issues.