Card: clearer fork_turn_index description

README.md

@@ -219,7 +219,7 @@ python scripts/download_data.py      # -> datasets/dialfork/ (+ datasets/STAR/)
 | `variant_id` | string | the instruction that was injected (e.g. `goal_collect_feedback`) |
 | `fork_position` | int | *k* in 1..4 (1 = earliest fork, most deviant); empty for conformant dialogues |
 | `fork_assistant_turn` | int | *t<sub>k</sub>*: the 1-based **assistant** turn the deviation starts at (counting assistant turns only) |
-| `fork_turn_index` | int | the same turn as a 0-based position in `turns` (both speakers): `turns[:fork_turn_index]` is the part before the fork; what Task 3 predicts |
+| `fork_turn_index` | int | the same turn as a 0-based position in `turns` (both speakers). This is the value Task 3 asks to predict. (`turns[:fork_turn_index]` is the part before the fork) |
 | `num_turns` | int | number of turns (both speakers) |
 | `turns` | list | the conversation: `[{speaker, text}, ...]` |
 | `dialog_json` | string | the complete original file: personas, generation settings and seed, the full event trace (injected instruction included), and the task's workflow |