Date: 09/16/2002 at 17:10:15 From: Tyler Smith Subject: Estimation Why do we use estimation?
Date: 09/16/2002 at 18:34:32 From: Doctor Ian Subject: Re: Estimation Hi Tyler, The _point_ of estimating things is that estimating will save you space, time, or effort, and in return for those savings, you agree to pay a price in accuracy. There are lots of different ways to estimate things: you can eliminate digits from a number (truncation or rounding), you can replace a decimal number with a fraction (which, technically, is the same thing), you can replace any number with a 'nearby' number that's easier to work with, you can use a graph to replace a list of individual values, you can use a simple function in place of a more complicated function, and so on. In each case, you're making a trade-off: "It's not going to hurt much if my answer is off by a little bit, especially if I can get that answer ten times more quickly, or by storing a thousand times less information." The _art_ of estimating things properly requires two different sets of skills. The easier one is learning the various techniques of estimation: rounding, graphing, and so on. The harder one is learning to recognize how much accuracy you can afford to throw away in a given situation, and how much benefit you'll get from doing it. Does this help? - Doctor Ian, The Math Forum http://mathforum.org/dr.math/
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