rich1.0David A. Harding (npub1sy…46ksu)https://yabu.me/npub1syluunzwwmc70d85d9alzqc2jrc6pdur7xrax2vqpfxas6tljavsa46ksunjumphttps://yabu.meYou detect it with statistical analysis. If Mallory is excessively unlucky, e.g. she's submitted 3x as many shares as necessary to find a block but none of her shares were blocks, you ban her.