You can read his methodology in the blog entry, but to sum up, he tried to control for the different factors that increase flight cost, like flying longer distances or flying to smaller airports that can't take advantage of economies of scale. Then he used data from the Bureau of Transportation to try to match similar itineraries among different airports and then compare costs to find a fair market value, and then compare that to the actual fare price. Other factors include distance from large cities or the presence of so-called "legacy airlines" like American or United.
Houston's Bush Intercontinental Airport (Texans, apparently, can't settle for just being "international") wins the overcharge race among the nation's busiest aiports. Silver says they tack an extra $85 onto the cost of a ticket for flying out of Houston. Newark International Airport charges you an extra $72 for flying out of New Jersey, which might actually be money well spent considering that you are flying out of New Jersey.
On the other end, Ft. Lauderdale Hollywood Airport in Florida charges you less than the market cost by $90. Silver says that the high traffic at destinations like Florida or Las Vegas could help explain how the charges can be kept lower.
A check of the chart that compares all of the top 230 airports in the country shows that all three Oklahoma airports on the list are in the overcharge bin. Tulsa International adds $45 to the fair market price, Will Rogers World Airport in Oklahoma City adds $54 and Lawton/Ft. Sill Regional wants an extra $151 from you to get over the