Set of Remaining Items in a Ranked Sequence

Plackett-Luce Loss Function

A model is designed to rank a set of three documents {Doc A, Doc B, Doc C} for a given user query. To calculate the log-probability of the specific ranked sequence 'Doc A > Doc B > Doc C', a developer proposes calculating the total log-probability as the sum of the log-probabilities of each document being chosen first from the full set of three documents. Why is this approach fundamentally flawed for modeling a sequential ranking process?

Ranked Sequence Log-Probability Calculation

Calculating Log-Probability for a Ranked List