Here is how the paper is defining it for it's purposes: "demographic diversity (e.g. age, nationality), cognitive diversity (e.g., personality traits, educatio

Here is how the paper is defining it for it's purposes: "demographic diversity (e.g. age, nationality), cognitive diversity (e.g., personality traits, education level) and job-related diversity (e.g., function, tenure), with a focus on the first two dimensions."