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Average centipawn value not calculated correctly?

Asked by studentt
Tags question about analysis
Activity Viewed 232 times, last updated
I have a self-made game:

I try to verify the average centipawn loss for the white player, which is 72:

100 * (0.2 + 1.0 + 0.8) / 3 = 66.67

- 0.2 because the initially evaluation gives 0.0 score but after 1.a4, the evaluation drops to 0.2
- 1.0 because the evaluation before 2.Ra2 is +0.4 but after 2.Ra2, the evaluation drops to -0.6
- Similarly for 0.8

How does the lichess software derived 72, when the correct average centipawn loss should have been 66.67?

2 Answers
Answered by jmcampbell
1) The initial evaluation is +0.1, not 0. So the calculation is:
100 * (0.3 + 1.0 + 0.8) / 3 = 70

2) The engine only displays one decimal place of precision. So what you think is a 1.0 might actually be a 1.04, and instead of 0.8 it might actually be 0.82. This example would give an average centipawn loss of 72.
Answered by DoTheMath
Lots of good information in the comments and posted URLs:

A post made by user kettwiesel has the guts of it:

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