Table 1.

Formulation notations.

Input parameters
E	The set of candidates, i ∈ 1, …|E|
J	The set of open positions (jobs), j ∈ 1, …|J|
qij	Equals 1 if candidate i is qualified for position j, 0 otherwise
Pij	Probability for candidate i to succeed in position j
Nj	Number of open jobs in position j
Vj	Value of a successful recruitment to position j
T	Set of candidate class types, t ∈ 1, …|T|
bit	Equals 1 if candidate i belongs to class t, 0 otherwise
PRjt	Required proportion of workers of class t in position j
B	A parameter that balances accuracy and demand objectives

Indices
i	Candidate
j	Position
t	Class types of candidates

Decision variables
Xij	Recruitment of candidate i to position j
Yj	The difference between required and recruited employees for position j
Ymax	Maximum allowed difference between required and recruited employees
Zjt	Number of candidates of type t recruited to position j