Handicap adjustment should consider "proper handicap"

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Handicap adjustment should consider "proper handicap"

[anoek]

FYI I've been playing with this, honestly it doesn't seem to make that much of a difference, so much so that I'm not sure if it's better or worse, it's kind of lost in the noise. I'll continue running it in tests though and if something meaningful emerges I'll run with it.

You might be right with that diagnosis.

Anyway I took a peek at that commit above and it seems to me that the handicap is only adjusted if it is == 1, but I think it should always be adjusted if it is >= 1.

So this

    if HALF_STONE_HANDICAP:
        return rank_to_rating(rating_to_rank(rating) + (0.5 if handicap == 1 else handicap)) - rating
    return rank_to_rating(rating_to_rank(rating) + handicap) - rating

should imo be changed to

    if HALF_STONE_HANDICAP:
        return rank_to_rating(rating_to_rank(rating) + (handicap + 0.5 if handicap > 0 else 0)) - rating
    return rank_to_rating(rating_to_rank(rating) + handicap) - rating

Now I'm unsure if it should be +0.5 or -0.5

[anoek]

oh probably -0.5, might change things. I had a version that applied for > 0 as well, I'll try it again with -0.5