I'm curious about the difference between the calculator and phone layouts.
I expect that the bias to the winning phone design came because of the bias in phone numbers - that is, because rotary dial phones would dial lower numbers more quickly, lower numbers were more sought after, and were allocated to higher population areas. This was both for personal convenience, and because it tied up the phone lines for less time with the dialing pulses.
I expect that this asymmetry also introduced a bias toward the 1-on-top dialing pattern that won, though I don't see analysis to that effect. (The original paper simply stated "that the arrangement frequently found in ten-key adding machines...was not the best [in its group]...the same geometric configuration with a different numbering scheme [one on top] was superior in keying performance... However the performance differences between the two were small".
Of course, the two arrangements primarily differ in which keys are obscured by your hand, and the proximity of the 0 key, which shouldn't be commonly used, so maybe this is just post-hoc reasoning...
I expect that the bias to the winning phone design came because of the bias in phone numbers - that is, because rotary dial phones would dial lower numbers more quickly, lower numbers were more sought after, and were allocated to higher population areas. This was both for personal convenience, and because it tied up the phone lines for less time with the dialing pulses.
I expect that this asymmetry also introduced a bias toward the 1-on-top dialing pattern that won, though I don't see analysis to that effect. (The original paper simply stated "that the arrangement frequently found in ten-key adding machines...was not the best [in its group]...the same geometric configuration with a different numbering scheme [one on top] was superior in keying performance... However the performance differences between the two were small".
Of course, the two arrangements primarily differ in which keys are obscured by your hand, and the proximity of the 0 key, which shouldn't be commonly used, so maybe this is just post-hoc reasoning...