Structure of a complexity index of a test physic problemin the Rasch model

In today's theory of IRT testing the solution to a test task is seen as a probabilistic event, depending on the
student's level of knowledge and the level of complexity of the assignment. It is noted that in the scientific
literature there is no common approach to determining the factors influencing the complexity of the problem. It
is suggested that the difficulty of the problem increases with the number of key elements, which are the data
elements used in solving the problem. On the basis of the statistical analysis of solutions of specially designed
test tasks it was concluded that there is a linear dependence of the complexity of the problem in the Rasсh
Номер задачи, j 1 2 3 4 5
m 7 9 5 6 7
bj (логиты) 0,44 4,81 -2,70 -1,02 0,44
model on the number of key elements of the solution. This result allows on the development stage of test
problems to realistically assess their complexity and to predict the result of testing.

Rasch model, complexity index of a problem, cognitive operations