@techreport{NBERw13487,
 title = "Optimal Mortgage Refinancing: A Closed Form Solution",
 author = "Sumit Agarwal and John C. Driscoll and David Laibson",
 institution = "National Bureau of Economic Research",
 type = "Working Paper",
 series = "Working Paper Series",
 number = "13487",
 year = "2007",
 month = "October",
 URL = "http://www.nber.org/papers/w13487",
 abstract = {We derive the first closed-form optimal mortgage refinancing rule. The expression is derived by using the Lambert-W function to solve a tractable class of mortgage refinancing problems.  We calibrate our solution and show that our quantitative results closely match those reported by researchers who use numerical methods.},
}