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POWER SIMULATION -- naive_a2_d0_5
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model: behavior ~ stim + day + stim:day + (1|rat)   (success COUNT; day within-window)
observed groups: stim n=3, control n=7   nrep=120, alpha=0.05
ground truth: stim:day=+6.96/day, rat SD=9.64, residual SD=12.11, days=6

 true stim:day interaction = +6.96 (100% of observed)
  N/group  | per-animal power | LME power
  ------------------------------------------
  3        |  0.43            |  0.85  <- observed
  5        |  0.87            |  0.96
  8        |  1.00            |  1.00
  12       |  1.00            |  1.00
  16       |  1.00            |  1.00
  24       |  1.00            |  1.00

 true stim:day interaction = +3.48 (50% of observed)
  N/group  | per-animal power | LME power
  ------------------------------------------
  3        |  0.12            |  0.31  <- observed
  5        |  0.33            |  0.42
  8        |  0.57            |  0.67
  12       |  0.74            |  0.81
  16       |  0.90            |  0.89
  24       |  0.97            |  0.99

Read the per-animal column as the honest power. At the observed N this study
is typically underpowered; per-animal power reaches ~0.8 only at larger N.