Ear Training Statistics:

Here are some interesting statistics from the Ear Trainer database.
These change in real time, as more people take the test.

I've recorded 870456 clicks so far.

Overall Distribution of Played Notes and Answers:

Answers: (blue = number of clicks)

Played
Notes:

Analysis:

The correct answer is the most common answer for each interval.

The minor 6th, and minor 7th are the most difficult intervals.

Overall, the wrong answers tended to be close to the right answers in pitch.

Minor 3rds are often mistaken for major 6ths, which is interesting because they are inversions of each other.

Played Note and Answer Combination vs. Average Time Taken:

Answers: (blue = longer time taken)

Played
Notes:

Time taken to answer:

Time taken: (seconds) (blue = number of clicks)

Played
Notes:

Time taken to answer vs. Accuracy:

Time Taken: (seconds) (blue = accuracy)

Played
Notes:

Overall Accuracy:

Minor 2nd	67.56%
Major 2nd	57.85%
Minor 3rd	47.00%
Major 3rd	57.74%
Perfect 4th	53.28%
Tritone	45.76%
Perfect 5th	56.13%
Minor 6th	39.61%
Major 6th	47.09%
Minor 7th	41.61%
Major 7th	52.72%
Octave	67.35%

Time Taken (left), Accuracy (right)

0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
5.8
6.0
6.2
6.4
6.6
6.8
7.0
7.2
7.4
7.6
7.8
8.0
8.2
8.4
8.6
8.8
9.0
9.2
9.4
9.6
9.8
10.0

0.4	10.48%
0.6	9.92%
0.8	15.27%
1.0	32.52%
1.2	50.59%
1.4	58.84%
1.6	61.71%
1.8	60.00%
2.0	57.59%
2.2	43.56%
2.4	41.52%
2.6	40.13%
2.8	54.40%
3.0	74.91%
3.2	78.49%
3.4	75.55%
3.6	71.50%
3.8	66.22%
4.0	61.51%
4.2	56.70%
4.4	53.50%
4.6	51.71%
4.8	49.50%
5.0	48.10%
5.2	47.58%
5.4	46.90%
5.6	45.55%
5.8	45.32%
6.0	44.43%
6.2	44.74%
6.4	43.57%
6.6	44.21%
6.8	43.13%
7.0	43.23%
7.2	42.36%
7.4	42.65%
7.6	42.99%
7.8	42.50%
8.0	42.13%
8.2	42.74%
8.4	40.80%
8.6	40.73%
8.8	41.53%
9.0	41.13%
9.2	40.80%
9.4	39.19%
9.6	40.57%
9.8	40.47%
10.0	40.13%

Overall distribution:

This is how correct, or far off listeners were in identifying notes. Negative means they answered too low, zero means they answered correctly, and positive means they answered too high.

-12
-11
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
10
11
12

Number of Intervals enabled vs. Accuracy:

1
2
3
4
5
6
7
8
9
10
11
12