I've been recording my times for the last 500 puzzles in each category to see if I'm improving or if I have reach a plateau. While that's probably of no interest to anyone else, some people might be interested to know what the average numbers for the record times are for the various puzzle sizes. So, here they are:

Mean: 30.38 s (standard deviation 1.47 s)

Mode: 30 s (what a shock!)

Median: 30 s (also a stunner)

Mean: 40.90 s (s.d. 7.81 s)

Mode: 35 s

Median: 38 s

Mean: 56.46 s (s.d. 10.01 s)

Mode: 50 s

Median: 52 s

Mean: 79.83 s (s.d. 13.19)

Mode: 70 s

Median: 74 s

Mean: 122.11 s (s.d. 23.36)

Mode: 98 s

Median: 116 s

Mean: 141.75 (s.d. 20.53)

Mode: 120 s

Median: 136.5

I thought it was interesting that the modes for the 4x7s, 4x5s, 4x4s, and 3x4s are the minimum times, but that it isn't true for the 3x5s (which seems to be 34 s minimum) or 4x6s (which seems to be 96 s). I also thought it intriguing that the standard deviation for 4x7s was smaller than for 4x6s.

If anyone is interested in other statistical information about this data set please feel free to ask. One caveat about the data, though, is that an unequal number of entries in each category are duplicated because I was assigned the same puzzle more than once. I don't think such duplicates account for more than 1% of any category, so the bias is likely to be insignificant, but still worth mentioning.

**Size 3x4**Mean: 30.38 s (standard deviation 1.47 s)

Mode: 30 s (what a shock!)

Median: 30 s (also a stunner)

**Size 3x5**Mean: 40.90 s (s.d. 7.81 s)

Mode: 35 s

Median: 38 s

**Size 4x4**Mean: 56.46 s (s.d. 10.01 s)

Mode: 50 s

Median: 52 s

**Size 4x5**Mean: 79.83 s (s.d. 13.19)

Mode: 70 s

Median: 74 s

**Size 4x6**Mean: 122.11 s (s.d. 23.36)

Mode: 98 s

Median: 116 s

**Size 4x7**Mean: 141.75 (s.d. 20.53)

Mode: 120 s

Median: 136.5

I thought it was interesting that the modes for the 4x7s, 4x5s, 4x4s, and 3x4s are the minimum times, but that it isn't true for the 3x5s (which seems to be 34 s minimum) or 4x6s (which seems to be 96 s). I also thought it intriguing that the standard deviation for 4x7s was smaller than for 4x6s.

If anyone is interested in other statistical information about this data set please feel free to ask. One caveat about the data, though, is that an unequal number of entries in each category are duplicated because I was assigned the same puzzle more than once. I don't think such duplicates account for more than 1% of any category, so the bias is likely to be insignificant, but still worth mentioning.

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