Retrospective report

Week of 28 September 2026

Week-Ahead Model - MAX_AVAIL

Per-region forecast accuracy for the Week-Ahead Model - MAX_AVAIL model group over the week of 28 September 2026.

Model revision 2

Generated 5 October 2026 at 9:07 am (Sydney time)

Region	MAE¹	Bias²	Average predicted price	Average actual price	Price spike windows³
NSW1	28.13	-6.41	$73.10	$79.50	0
QLD1	24.98	11.25	$67.34	$56.09	0
SA1	44.40	-13.32	$53.43	$66.75	1
VIC1	33.61	-13.07	$38.41	$51.48	0

¹Mean Absolute Error (MAE) is the average absolute difference between forecast and actual prices.

²Bias is the average difference between forecast and actual prices.

³To maintain an informative scale, we charted price spikes separately to other prices. We plotted the 6 hours before and after the RRP exceeded $500 as separate, region-specific charts. These price spikes are capped at $500 in the full region prediction charts.

NSW1

Region	MAE	Bias	Average predicted price	Average actual price	Price spike windows
NSW1	28.13	-6.41	$73.10	$79.50	0

QLD1

Region	MAE	Bias	Average predicted price	Average actual price	Price spike windows
QLD1	24.98	11.25	$67.34	$56.09	0

SA1

Region	MAE	Bias	Average predicted price	Average actual price	Price spike windows
SA1	44.40	-13.32	$53.43	$66.75	1

Change in Forecasted Prices over the Price Spike in SA1 between 2026-09-30 12:30:00 and 2026-10-01 03:00:00

Change in Forecasted Prices over the Prediction Interval in SA1 using Week-Ahead Model - MAX_AVAIL (Without Price Spikes)

VIC1

Region	MAE	Bias	Average predicted price	Average actual price	Price spike windows
VIC1	33.61	-13.07	$38.41	$51.48	0