In 2016, a worldwide study of workplace fraud found that initial detections of fraud resulted from a tip (39.1%), an internal audit (16.5%), management review (13.4%), detection by accident (5.6%), account reconciliation (5.5%), surveillance/monitoring (1.9%), confession (1.3%), or some other means (16.7%). Use a Pareto chart to organize the data.

Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.