Lawrence Weinstein’s new book, Guesstimation 2.0: Solving Today’s Problems on the Back of a Napkin, shows how to estimate everything from how closely you can orbit a neutron star without being pulled apart by gravity, to the fuel used to transport your food from the farm to the store, to the total length of all toilet paper used in the United States — handy tips for anyone prepping for a job interview in technology or finance, or trying to astound their kids. Today he offers the next in his series of election-themed problems. Read on to see how to estimate an answer to How many telephone robo-calls will be made during the campaign season?
Answer: We could try to estimate this by considering each state individually, looking at the competitiveness of its elections in both the primary and the general election and considering the number of candidates running in each election. Voters in very competitive states would receive dozens of robo-calls and voters in other states would receive very few. We could further break this down by estimating the proportion of households with land lines and with cell phones. However, this is much too much work.
Instead let’s estimate that each household receives more than one and less than 100 robo-calls. Taking the geometric mean, this gives 10 robo-calls per household. The population of the US is about people giving about 108 households. At 10 calls per household, this gives
N=(10^8 households) (10 calls/household)
of one billion robo-calls. That seems like a lot.
At a mere ten seconds wasted per call, that is 1010 wasted seconds or 300 wasted years of our time!
Copyright 2012, Lawrence Weinstein.
Lawrence Weinstein is University Professor of Physics at Old Dominion University. He is the coauthor of Guesstimation: Solving the World’s Problems on the Back of a Cocktail Napkin (Princeton).