Using z-scores to compare different populations The International Average Salary Income Database provides a comparison of average salaries for various professions. The data are gathered from publications and reports obtained directly from government agencies (such as the US Bureau of Labor Statistics) or from the International Labour Organization.
Suppose an industrial/organizational psychologist is interested in the relationships between job satisfaction, job performance, and job compensation. She has data from five different countries on the average monthly salaries paid to computer programmers. She begins her analysis by converting all of the salary data into US dollars:
Country
Average Monthly Salary(US dollars)
Standard Deviation(US dollars)
Original Currency
the Czech Republic $1,059 $158.80 koruna
Latvia $790 $118.60 lat
Korea $2,245 $673.60 won
Romania $646 $96.80 leu
the United States $4,141 $1,242.20 dollar
To appreciate the differences among the countries, she calculates the z-scores for a computer programmer making $1,500 per month. Use the dropdown menus to complete the following table.
Country
z-score for $1,500 Salary
the Czech Republic
Latvia
Korea
Romania
the United States
Suppose a computer programmer in each of the five countries listed is offered a salary of $1,500 per month. Using the z-scores and assuming that the computer programmer prefers a salary that has a higher relative value, the computer programmer from will likely be the most pleased with the offer, because a salary of $1,500 per month for this country corresponds to the