Schweser Different for Selection Effect

Book 5 Page 94 they say selection effect equals weight in the benchmark multiplied by the portfolio return minus benchmark return for each sector. Wb*(Rp-Rb) Then in global evaluation on page 149 they say that security selection effect equals weight in the portfolio multiplied by return in portfolio minus return in benchmark for each sector Wp*(Rp-Rb) I am not following the difference here. Granted the second equation is in Global Evaluation, so something may be done differently, but I am not following it. Can anyone explain this?

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