It is my understanding that in statistics one has 4 basic data types: nominal, ordinal, ratio, and interval.
I see cases where people refer to "count data" (which is a random variable whose range is the set of whole numbers, such as the number of accidents in a week or the number of passengers on a plane), which brings me to my question: is "count data" is really data. It seems to me that it is a statistic computed from nominal data for two reasons. First, it doesn't seem to fall into one of the four data type categories. Secondly, it is obtained not from a measurement or recording of single events but rather from an arithmetic operation (i.e. addition). So for example, the number of passengers in a plane is a statistic whch would be computed from the nominal data associated with each seat in the plane ("1" = occupied, "0" = unoccupied).