Learn R Programming

ankiR (version 0.6.0)

fsrs_interval: Calculate next interval for desired retention

Description

Given a stability value and desired retention, calculates how many days until the card should be reviewed.

Usage

fsrs_interval(stability, desired_retention = 0.9, decay = 0.5)

Value

Interval in days until next review

Arguments

stability

Stability (S) in days

desired_retention

Target retention rate (default 0.9 = 90%)

decay

Decay parameter (w20). Default 0.5 is FSRS-4.5 value.

Details

Derived from the retrievability formula by solving for t: $$I(r, S) = S / factor \cdot (r^{-1/decay} - 1)$$