Variance and Width

1.Variance
  In last post, I have mentioned that my next step is to use variance to distinguish some errors in material recognition. While it turns out that it doesn't work.  For some specific materials, variance can be a good measurement, like metal. But in error detecting, variance need to be valid for all kinds of materials so that I can use it to modify the errors. But variance can't work for several materials, like the picture shown below.  I have sorted all the training and testing data's variance, and ind1 and ind2 show the sequence of the variance. The last 6 material's variances of their training and testing data can't be corresponded to each other.

2. Width
   When using width to help recognize the material, the error increase to 5 in 10 (original is 2 in 10). I think maybe because widths are not unique among materials.

  So I think I'm gonna stop in 2 errors in 10 materials, and start working on rectifying each pictures' deformation, which is the main problem of the new dataset.