Ace the Certified Information Systems Auditor Exam 2025 – Audit Your Way to Success!

Using statistical sampling is preferable for an IS auditor when there is a need to objectively quantify the probability of error. Statistical sampling allows for the calculation of error rates and confidence intervals, providing a scientific approach to ensure that the sample results can be projected to the total population. This method includes the ability to estimate the likelihood of an error occurring, making it suitable for situations where accurate quantification of risk is essential.

The objective nature of statistical sampling contrasts with judgment sampling, where decisions are made based on the auditor's experience or intuition. This objectivity is particularly important in audits where regulatory compliance or high-stakes decisions are involved, as it helps auditors provide quantifiable evidence to support their conclusions.

In contrast, using statistical sampling does not necessarily correlate with the size of the teams audited, the amount of time available, or the auditor's personal experience. Small teams may not require statistical methods, while time constraints often lead to more convenient methods rather than those needing extensive statistical analysis. Additionally, prior experience of the auditor can enhance the selection process but doesn't inherently provide the objectivity that statistical sampling offers.