anchor: It suggests, in particular, that what might seem to a naive commentator like a natural conclusion--if productivity growth in the steel industry reduces the number of jobs for steelworkers, then productivity growth in the economy as a whole reduces employment in the economy as a whole--may well involve a crucial fallacy of composition.
positive: As a parallel, productivity growth in the economy will reduce employment in the economy.
negative: Steelworker jobs increase with productivity growth.