These tests are flawed because the absolute value of the money we're dealing with is too much of a variable between subjects. $1500 is not much for subject A to

These tests are flawed because the absolute value of the money we're dealing with is too much of a variable between subjects. $1500 is not much for subject A to lose or gain but it is for subject B. A test should account for that if we want results to be comparable across subjects.