Mean, Median, and Mode in Real Life
Date: 12/21/96 at 20:06:06 From: Brian Beck Subject: Mode if more than 2 numbers repeat and if there are no repeated numbers. I was teaching about mean, median and mode the other day, and everything was going well. The students seemed to understand what we were doing, although it was not clear why we needed to know three different methods for finding central tendencies. The question came up about how to determine the mode if there was more than one number in a list that repeated. My suggestion was that there could be more than one mode, and an answer in the teacher's guide also indicated the same thing. The other question asked how to figure out the mode if no numbers in the list repeated. Again, my answer (from the guide) was that there was no mode. Was I correct? Please explain why. If I was incorrect, please explain the correct responses. Thank you. Brian Beck Grade 7 teacher
Date: 12/21/96 at 21:05:07 From: Doctor Ceeks Subject: Re: Mode if more than 2 numbers repeat and if there are no repeated numbers. Hi, Identifying "the" mode is an attempt to answer the question: "Which occurs most frequently?" Sometimes there's a clear answer, other times there are a few answers, and sometimes everything comes up the same amount and there's no point in asking or answering that question. So your answers are fine. You could also say that all the items in a list where no item is repeated are modes, but there's not much point. Anyway, the answer to "what is the mode" in such a non-repeating list is a technical matter, and it's more important to understand that the question itself becomes rather inapplicable in such situations. Here are examples of situations to illustrate when the three different methods of finding central tendencies are useful: Fashion is generally an answer to the question, "What is the mode?" e.g. "What's the most popular sneaker?" or "What shirt style would most people want to wear?" Of the two outcomes: "strike out" or "base hit or better," assigning 0 to "strike out" and 1 to "base hit or better" and then averaging is more useful to a manager than determining the mode, which in pro baseball is for everybody to "get out." (At least, I can't think of anybody with a batting average over 500... was there ever such a phenomenon?) Knowing the median test score is important to people who want to think they are in the "better half of the population." -Doctor Ceeks, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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