premierach

Premierach is a neologism used in theoretical discussions of sequential decision making, particularly in artificial intelligence and cognitive science. It refers to the first instance in a task sequence when an agent achieves a predefined goal or meets a performance threshold for the first time. The concept helps distinguish initial success from ongoing improvements observed later in learning curves.

Etymology and scope: The term blends premier, meaning first, with ach, an abbreviation of achievement. It is used primarily in academic papers, experiment logs, and curricula that emphasize learning progression rather than final performance.

Applications: Researchers apply premierach to quantify learning speed, compare learning algorithms, and diagnose early-stage difficulties. In experiments, premierach is reported as the earliest time step (or episode) where the criterion is met, along with the criteria used, such as reward threshold or success rate.

Relation to related concepts: Premierach is related to first passage time, milestone attainment, and early stopping criteria. It is distinct from ultimate or asymptotic performance, focusing specifically on the initial attainment of the goal.

Critiques and limitations: The interpretation of premierach can be sensitive to task design, reward shaping, and threshold choice. It does not capture durability of success or long-term stability, so it is typically complemented by additional metrics.

See also: First-passage time, Milestones in learning, Curriculum learning, Reinforcement learning, Performance metrics.