What challenge does "big data" bring to HR? Responses Concerns over the privacy of candidate data because HR systems are hacked often. Concerns over the privacy of candidate data because HR systems are hacked often. Increased pressure for HR to use metrics and in-depth analysis for decision making and to justify return on investment for key expenditures. Increased pressure for HR to use metrics and in-depth analysis for decision making and to justify return on investment for key expenditures. Less of a paper trail for employees, frequently documents are digital. Less of a paper trail for employees, frequently documents are digital. Concerns over productivity and communication