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Weighted Average???
Message posted by Cayman Little on September 18, 2000 at 12:00 AM (ET)
What is weighted average? How do you calculate it?
READERS RESPOND:
(In chronological order. Most recent at the bottom.)
Re: Weighted Average???
Message posted by JG on September 19, 2000 at 12:00 AM (ET)
A weighted average is a modified version of an arithmetic mean. An average of 5 and 7 is 12/2=6, but we can count 5 twice so that a weighted average is 17/3=5.67, etc.
Re: Weighted Average???
Message posted by Jessica on September 19, 2000 at 12:00 AM (ET)
Instead of where means are averaged down a column, quantities are taken into account. I use this everyday.
If Student A took 4 tests with an average score of 90, and Student B took 20 tests with an average score of 50, then the weighted average score for both is 56.65-- not 70 like a regular average. 90*(4/24)+50*(20/24)
Re: Weighted Average???
Message posted by DL on September 19, 2000 at 12:00 AM (ET)
For example, if you have a scale of time from 1-10 and you try to find the value at time=8, but you only have at 1 and 10, the value at time=8 will be affected (or depend) more from time=10 than the ones at time=1, you weight the importance of the value at 10 more that at 1 to obtain the estimate.Value at 8 = (Value at 10 * Weigth at 10 + Value at 1 * Weigth at 1 ) / ( Weigth at 10 + Weigth at 1 )
You can also use more values with their weigths.
Re: Weighted Average???
Message posted by Ben Durant (via 207.4.162.98) on May 28, 2001 at 4:47 PM (ET)
Jessica's answer is misleading. In her example, she says that the "weighted" average is 56.6% and the "regular" average is 70%. Actually, it's the other way around - the "weighted" average is 70, since it is derived from inflating the weight of 4 of the 24 tests from 16.6% to 50%. The "regular" average is 56.6% since each of the 24 tests has the same value (one-twentyfourth of the total tests).
Confused to count weighted average !
Message posted by Kevie (via 161.142.15.152) on June 13, 2001 at 10:04 AM (ET)
I am conducting a research about quality management practices in Indonesian manufacturing organizations. I use questionnaire to collect data from my respondents. Now I get confused how to calculate the 'weighted average'for part of my quest. A part of my quest has 20 statements that divide by six factors. Anybody know how to count the overall score of the six factors with the'weighted average'. I'm sure that's not simply just add the mean of each factors and I can get the score !!
Thanks a lot !
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