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I have a list of values each with a corresponding error. I can determine the average/mean of the list, but I'm not sure how to best calculate the error over the entire population.

e.g.

107 +/- 0.2 120 +/- 0.1 184 +/- 0.4 44  +/- 0.3 

Average is simply 113.75, but what is the error?

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    I've clarified by question a little by removing "average error" as I don't think that's what I'm after exactly. What I need to work out is the error of the whole dataset when averaged.2012-05-20

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If errors can be either negative or positive it does not make sense to average them because positive errors cancel negative error. That is why statisticians use variance (average squared error) or the mean absolute error to summarize the magnitude of the errors.

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    So the line is forced to move closer to the outlier at the expense of the other observations. Absolute eror is the absolute value of the error so with average absolute error we take the absolute value of the error and average it. Using that criteria the penalty for a large error is big by not nearly as big as for least squares. So it is less influenced by outliers and doesn't sacrifice the accuracy at the other points as much. So we say it is robust against outliers.2012-05-19