Split a group project grade among members.
Individual weighting turns a single group mark into per-member grades. The equal share is simply one divided by the number of members; your contribution factor is your assessed share divided by that baseline, so 1.0 means you pulled exactly your weight. The factor is then damped by the adjustment weight the rubric allows — at 25%, a member who did double their share gains a quarter of that advantage rather than all of it. That damping is deliberate: peer assessments are noisy, and an undamped factor would let one hostile rating dominate a mark.
Individual grade from a group mark
Individual = group grade x (1 + (contribution share / equal share - 1) x adjustment weight)
Every contribution factor is 1.0, the adjustment term is zero and each member receives the group grade unchanged. That is the intended default behaviour.
Yes, if the whole group is being assessed. If the shares your group reports sum to more or less than 100%, normalise them first or the factors will be systematically inflated or deflated.
Because peer ratings carry real bias — friendship, visibility of work and confidence all distort them. Damping preserves the signal while limiting the damage a single unfair rating can do.