Take A Sweater
By Harvard University
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Description
NOTE: Take-A-Sweater currently only has data for Boston, MA. This will be changing with the next release.
This App was created in 2012, for use in the Harvard University General Education course "The Art of Numbers," taught by Prof. Alyssa Goodman. The code was written by Bill Barthelmy of Harvard’s Academic Technology Group. Historical data were kindly provided by ForecastWatch, a product of Intellovations, LLC. Current five-day weather forecast data are provided by NOAA.
Our goal in creating this App was to offer an example of how the "uncertainty" associated with computer modeling and prediction can best be displayed, and how uncertain predictions are used in everyday life.
Take-A-Sweater? uses historical weather records to compare currently predicted temperatures with what actually happened under similar conditions in the past. "Similar conditions" are defined in "Settings" to be within "Date Tolerance" days of the present calendar date and "Temperature Tolerance" degrees of the current predictions for each of the next five days.
For example, imagine that: today is February 9; the high temperature 3 days from now (on February 12) is predicted to be 43°; date tolerance = 6 days; and temperature tolerance = 3 degrees. To create the distribution you’ll see on-screen for 3 days out (February 12), Take-A-Sweater? will search its database, which extends back to 2005, for all past 3-day-out predictions of a highs between 40 and 46 degrees, during a range of calendar dates from February 3 to February 15.
iPhone Screenshots



Customer Reviews
Weather Forecast with Uncertainty
This is great—it gives the weather forecast with bars showing historical uncertainty. Only Boston for now, but other cities coming soon!
- Free
- Category: Weather
- Released: Mar 21, 2014
- Version: 1.0
- Size: 17.2 MB
- Languages: English, German
- Seller: Harvard University
- Copyright © 2014 The President and Fellows of Harvard College
Compatibility: Requires iOS 5.0 or later. Compatible with iPhone, iPad, and iPod touch.

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