On the Problem of Calculating the Variance of cost volume

[WesternTrail]

Use this to calculate the variance of cost volume in the program. If the number of views V=3, the calculation result should be as follows, right? But is this variance calculation consistent with the formula in the paper?

[zichen34]

The code is correct.

According to the eq. (2) in the paper, there is:

$$ \begin{aligned} \frac{ ∑_{i=1}^N (V_i - \bar{V} )^2 }{N} &= \frac{∑_{i=1}^N (V_i^2 - 2V_i \bar{V} + \bar{V}^2 ) }{N} \\ &= \frac{∑_{i=1}^N V_i^2}{N} - \frac{∑_{i=1}^N 2V_i \bar{V} }{N} + \frac{∑_{i=1}^N \bar{V}^2 }{N} \\ & = \frac{∑_{i=1}^N V_i^2}{N} - \frac{ 2\bar{V} ∑_{i=1}^N V_i }{N} + \frac{N \bar{V}^2}{N} \\ & = \frac{∑_{i=1}^N V_i^2}{N} - 2\bar{V}^2 + \bar{V}^2 \\ & = \frac{∑_{i=1}^N V_i^2}{N} - \bar{V}^2 \end{aligned} $$