Surprisal as an information measure was first defined by Myron Tribus in his 1961 book Thermostatics and Thermodynamics, so that it is equal in bits to the base-2 log of 1 over the probability, with the result that e.g. the number of choices equals 2 to the number of bits.

## Comments by thermochap

thermochap commented on the word surprisal

Surprisal as an information measure was first defined by Myron Tribus in his 1961 book Thermostatics and Thermodynamics, so that it is equal in bits to the base-2 log of 1 over the probability, with the result that e.g. the number of choices equals 2 to the number of bits.

September 28, 2015

thermochap commented on the word proper velocity

The proper velocity of an object is the map-frame distance traveled per unit proper-time on the clocks of the traveling object.

September 28, 2015

thermochap commented on the word proper time

Proper time is the frame-invariant time elapsed along the space-time trajectory of a clock traveling from one event to another.

September 28, 2015