- #1
rogo0034
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Homework Statement
Homework Equations
The Attempt at a Solution
Was able to get the population mean of 5.3 with 4*.2 + 5*.4 + 6*.3 + 7*.1
But for some reason I'm drawing blank for the variance (which i guess is .81)
rogo0034 said:Homework Statement
Homework Equations
The Attempt at a Solution
Was able to get the population mean of 5.3 with 4*.2 + 5*.4 + 6*.3 + 7*.1
But for some reason I'm drawing blank for the variance (which i guess is .81)
The variance of a weighted population is a measure of the spread or variability of the data points in a population, taking into account the weights assigned to each data point. It is calculated by taking the sum of the squared differences between each data point and the weighted mean, divided by the sum of the weights.
The variance of an unweighted population only considers the raw data values, while the variance of a weighted population takes into account the weights assigned to each data point. This means that data points with higher weights will have a greater impact on the overall variance.
The variance of a weighted population is useful in situations where the data points have varying levels of importance or significance. By taking into account the weights, we can get a more accurate measure of the variability of the data and make more informed decisions.
No, the variance of a weighted population cannot be negative. This is because the squared differences between each data point and the weighted mean will always result in a positive value, and when divided by the sum of the weights, it will always result in a positive variance.
The variance of a weighted population can be used in various statistical analyses such as hypothesis testing and confidence interval calculations. It can also be used to compare the variability between different populations with different weights assigned to their data points.