Mankiw stears us to an online calculator to determine at what rate someone ought to refinance a home mortgage. (The refinance decision is not an easy one since interest rates might very well drop after the refi decision has been made, plus there are up-front costs as well).
My favorite part is the disclaimer:
DISCLAIMER: This calculator describes the solution to a mathematical problem that is related to but not equivalent to a realistic mortgage refinancing decision. We make no warranty about the calculator’s accuracy, performance, or value as a source of practical advice. Use entirely at your own risk. The calculator is not endorsed by the National Bureau of Economic Research, the Federal Reserve Bank of Chicago, the Federal Reserve Board, or Harvard University.
DISCLAIMER: This post is not endorsed by Economic Policy Institute, MIT, Argmax.com it’s partners and affiliates, the Pope, or people named “Fred.” Does not contain arsenic, sulfates, or nutrients. Author makes no claim about the entertainment value of this post or it’s ability to cure psoriasis on contact. Pregnant women, or women who may become pregnant, or men who know women who may or may not become pregnant should consult a physician before using. Do not exceed recommended daily percentage. Click here to verify you have read and accept user agreement and home billing address. Not for use in whole or in part in products for commercial sale or those that compete with commercial products. Copyright (c) 2007–2047 (or until social security trust fund runs dry). All rights reserved, except for public broadcast, in which case you can use for the low-low-cost of $350 (Canadian) or 200 euro, whichever is greater using market exchange rates on date of broadcast. A bargain at twice the price.