# By Request: The Eyeball Test

After Phillies beat writer Bob Brookover wrote an article lampooning the idea that Sabermetrics have application to actual baseball, reader Scott suggested I repost something from last year that showed the unreliability of the human eye.

Click here to play “the eyeballing game”. You’ll be asked to perform some web-based geometric tasks testing the accuracy of your eyes. When you’re done, post your results in the comments below. My results from last year:

- Parallelogram: 2.8
- Midpoint: 2.2
- Bisect angle: 8.4
- Triangle center: 5.5
- Circle center: 4.0
- Right angle: 10.5
- Convergence: 4.1
**Average error**: 5.36

(I only did one run-through at the time.)

My results from just now:

- Parallelogram: 1.4, 3.6, 10.8
- Midpoint: 2.0, 5.1, 4.0
- Bisect angle: 1.0, 5.3, 1.6
- Triangle center: 46.2 (misclick), 5.2, 2.7
- Circle center: 1.0, 2.2, 2.2
- Right angle: 1.7, 19.0, 6.9
- Convergence: 7.0, 19.0, 14.4
**Average error**: 7.73

Conclusion: be very skeptical of what my eyes tell you. Be as skeptical of your own eyes.

## bje79

March 05, 2012 04:13 PM

Parallelogram 5.0 7.1 3.0

Midpoint 4.0 6.4 2.2

Bisect angle 3.1 0.5 1.4

Triangle center 7.4 7.2 1.6

Circle center 9.5 1.4 2.2

Right angle 1.8 1.9 11.8

Convergence 4.0 4.5 10.2

Average error: 4.58 (lower is better)

Time taken: 143.3

## Santos

March 05, 2012 04:15 PM

I must have done terrible. All I got was “This site is blocked by the Network Administrator”. Damn these eyes of mine.

## CITO

March 05, 2012 04:16 PM

Parallelogram 8.5 2.8 1.4

Midpoint 5.1 3.2 5.0

Bisect angle 12.3 2.5 0.2

Triangle center 4.5 2.0 7.8

Circle center 3.0 2.2 3.2

Right angle 1.1 3.5 0.4

Convergence 4.5 5.7 2.0

Average error: 3.85

Pretty proud of that 0.2 bisection.

## EricL @Eric_Lindros

March 05, 2012 04:18 PM

Parallelogram 2.0, 2.2, 2.2

Midpoint 2.2, 1.0, 2.0

Bisect angle 1.4, 4.3, 7.6

Triangle center 6.1, 4.5, 3.9

Circle center 6.3, 7.3, 2.0

Right angle 1.8, 3.7, 3.2

Convergence 2.2, 7.0, 6.3

Average error: 3.77, 119.9 sec

I’m less skeptical of my own eyes than I am of your eyes.

## Bill Baer @CrashburnAlley

March 05, 2012 04:20 PM

I’m incredibly near-sighted, so beating my score is like Shaq dunking on a small person.

## George Berry

March 05, 2012 04:21 PM

Parallelogram 6.3 10.3 24.0

Midpoint 12.7 6.1 15.1

Bisect angle 1.0 1.0 15.6

Triangle center 2.6 9.1 6.1

Circle center 4.5 10.4 7.0

Right angle 28.7 2.6 0.0

Convergence 7.2 8.0 13.5

Average error: 9.13 (lower is better)

Damn you, touchpad!

## Richard @yolacrary

March 05, 2012 04:22 PM

ha, awesome:

Parallelogram 1.0 13.6 7.6

Midpoint 4.0 3.0 1.0

Bisect angle 0.9 5.5 4.0

Triangle center 3.3 11.8 4.4

Circle center 12.2 2.2 6.7

Right angle 7.2 0.5 2.1

Convergence 1.4 2.2 12.0

## EricL @Eric_Lindros

March 05, 2012 04:22 PM

And like Shaq, you’re not aging well. You’re something like 40% worse this year than last. lol

## Bill Baer @CrashburnAlley

March 05, 2012 04:24 PM

and I got new specs like a month ago, too.

## Scott G @_Scott_G

March 05, 2012 04:35 PM

What a guy

## Dan

March 05, 2012 06:16 PM

I did pretty well. Hey, maybe I can be an over-rated BBWAA member too!

Parallelogram 9.2 1.4 7.8

Midpoint 2.2 5.1 2.2

Bisect angle 2.8 5.6 2.3

Triangle center 6.2 1.0 1.5

Circle center 4.5 6.0 6.0

Right angle 8.4 1.1 3.1

Convergence 2.2 12.0 2.0

Average error: 4.41 (lower is better)

Time taken: 131.2

## Jonny

March 05, 2012 06:31 PM

Parallelogram 2.2 3.2 6.4

Midpoint 9.4 1.0 1.0

Bisect angle 9.9 0.5 8.6

Triangle center 6.6 6.7 5.4

Circle center 4.5 1.0 5.4

Right angle 5.1 5.7 1.1

Convergence 6.4 6.7 2.2

Average error: 4.71 (lower is better)

Time taken: 253.2

Bah! And I was barely even trying… ;>)

## Giving_Chase

March 05, 2012 07:45 PM

Miss-clicked a couple times, but…

Parallelogram 12.2 18.8 1.0

Midpoint 3.0 2.2 4.0

Bisect angle 0.1 7.3 10.1

Triangle center 5.3 27.7 2.9

Circle center 2.8 10.3 2.8

Right angle 3.8 5.3 2.6

Convergence 16.1 14.4 4.5

I like that 0.1.

## Pete

March 05, 2012 09:15 PM

Parallelogram 2.0 1.0 3.6

Midpoint 3.2 5.1 1.4

Bisect angle 0.0 5.4 3.7

Triangle center 4.4 8.4 4.7

Circle center 5.8 3.6 2.2

Right angle 0.1 3.4 17.8

Convergence 14.3 5.0 12.2

Average error: 5.11 (lower is better)

Time taken: 220.4

Started strong with a 0.0 and a 0.1 in the first round, then regression!

## Max

March 06, 2012 09:42 AM

Parallelogram 10.8 2.2 8.0

Midpoint 1.0 5.0 1.0

Bisect angle 1.9 2.0 2.7

Triangle center 13.0 5.0 3.8

Circle center 5.0 10.0 9.1

Right angle 3.9 4.5 1.1

Convergence 2.2 5.4 4.2

Average error: 4.85 (lower is better)

Time taken: 199.6

## Ryan

March 06, 2012 09:51 AM

I did pretty well the second time that I took it…

Your inaccuracy by category:

Parallelogram 3.8 5.0 1.4

Midpoint 1.8 1.9 1.0

Bisect angle 4.9 3.0 0.7

Triangle center 2.7 2.6 0.3

Circle center 2.8 2.2 4.1

Right angle 3.4 0.2 0.3

Convergence 3.2 4.8 2.8

Average error: 2.52 (lower is better)

Time taken: 167.4

Perhaps there’s something to say about your eye getting better with practice.

## Ty

March 06, 2012 09:54 AM

Parallelogram 2.8 4.5 0.0

Midpoint 3.0 0.0 1.0

Bisect angle 6.7 3.7 0.0

Triangle center 2.4 4.2 5.5

Circle center 1.4 7.3 3.2

Right angle 0.5 0.1 5.5

Convergence 5.8 4.1 4.5

Average error: 3.15 (lower is better)

Time taken: 212.6

## Jeff T

March 06, 2012 10:55 AM

Your inaccuracy by category:

Parallelogram 25.9 28.0 85.0

Midpoint 7.8 1.6 10.6

Bisect angle 8.1 13.6 4.7

Triangle center 12.2 16.5 6.3

Circle center 5.2 7.6 8.7

Right angle 8.8 22.4 10.5

Convergence 6.1 6.7 16.6

Average error: 14.90

## Rob SJ

March 06, 2012 02:26 PM

I started to think I was getting better – a total of 0.1 on two consecutive categories. Then a 31.6. My mind doesn’t grasp the Triangle center thing very well.

Your inaccuracy by category:

Parallelogram 3.2 2.2 4.5

Midpoint 2.2 4.2 0.0

Bisect angle 0.6 3.5 1.0

Triangle center 2.3 14.8 31.6

Circle center 4.1 5.1 6.4

Right angle 7.2 0.2 6.5

Convergence 11.2 6.3 8.0

Average error: 5.96 (lower is better)

Time taken: 190.7

## Rob SJ

March 06, 2012 02:59 PM

took it again, final result 5.97. 0.01 worse.

## Radu

March 06, 2012 09:51 PM

Took the test one time only…

Parallelogram 4.0 1.0 8.0

Midpoint 6.7 2.0 4.1

Bisect angle 0.9 0.1 0.7

Triangle center 3.3 1.0 2.0

Circle center 4.1 2.2 1.4

Right angle 2.3 4.5 3.2

Convergence 9.1 3.0 3.2

Average error: 3.18 (lower is better)

Time taken: 178.9

## Bob

March 07, 2012 02:08 AM

Parallelogram 5.0 2.2 4.0

Midpoint 6.1 4.1 4.5

Bisect angle 5.4 3.0 0.1

Triangle center 7.7 5.9 6.2

Circle center 3.2 2.8 4.5

Right angle 8.2 2.1 4.5

Convergence 6.1 14.0 17.0

Average error: 5.55 (lower is better)

Time taken: 199.6

I actually thought Convergence was one of the harder tests.

## Professor59

March 08, 2012 04:53 PM

7.05 avg error

110 seconds

52 yr old w trifocals and I only took it once.

## Chris

March 09, 2012 11:21 AM

Parallelogram 1.0 3.2 4.1

Midpoint 2.2 1.0 1.0

Bisect angle 2.0 0.7 2.0

Triangle center 1.7 3.7 2.1

Circle center 1.4 5.4 4.2

Right angle 1.7 2.0 3.5

Convergence 2.0 1.4 1.0

Average error: 2.25 (lower is better)

Time taken: 369.6