Perceptle Count practice

Count looks like the easy opener and then punishes a guess. The client places between 45 and 85 dots, with at least 16 units between them, inside a 700 by 400 region, and shows them for 2,000 ms. You type an integer. The error is |guess − actual| / actual, not the raw number of dots. σ is 0.20 on a normal day and 0.32 on Friday, when the same dots drift for 2,600 ms.

On #97 I typed 1 as a calibration, and the HUD said “off by 48 dots,” so the puzzle was 49. One dot of error on 49 is 2.04% and scores about 99. Five dots score about 88. I do better when I chunk by fives and only then look at the leftovers, instead of counting left to right until the flash ends.

Trainer

The dots below are generated here. They are not the official layout, and the caption on any still image says the same thing.

• Group in fives or tens. A field of about 50 is five groups of ten, not fifty individual looks.
• Friday dots move. Track clusters, not a frozen count you started on the left.
• The number keys can cover the next button on a phone. Submit, then scroll if the next test does not appear.
• Relative error means a miss of two dots hurts more on a 45-dot puzzle than on an 85-dot one.