Time series analysis is a regression model in which the independent variable is time. In time series analysis, the value of the next time period is frequently dependent on the value of the time period before that. Hence, the error terms are usually correlated or dependent on the prior period; i.e., they are characterized by autocorrelation serial correlation).

Reference: IIA Business Knowledge for Internal Auditing, IT General Controls section.

* Understanding Data Analysis in Internal Auditing
* Data analytics enhances audit testing by identifying patterns, anomalies, and high-risk transactions within large datasets.
* Advanced analytics tools (e.g., AI, machine learning, continuous auditing) help auditors pinpoint areas of fraud, compliance violations, or operational inefficiencies.
* Why Option B is Correct?
* Data analysis improves risk assessment by allowing auditors to focus on high-risk areas, such as fraudulent transactions or control weaknesses.
* IIA Standard 1220 - Due Professional Care requires auditors to use technology to improve audit effectiveness, including identifying risks.
* IIA GTAG (Global Technology Audit Guide) 16 - Data Analytics supports using analytics to enhance risk-based auditing.
* Why Other Options Are Incorrect?
* Option A (Improves effectiveness of spot check testing techniques):
* Data analysis enables continuous and full-population testing, rather than just improving spot checks.
* Option C (Reduces the overall scope of the audit engagement):
* Analytics refines audit focus but does not necessarily reduce the scope; it may expand testing capabilities.
* Option D (Increases the auditor's objectivity):
* Objectivity is an ethical requirement rather than a direct effect of data analysis.
* Data analytics enhances internal audit testing by providing deeper insights into high-risk areas.
* IIA Standard 1220 and GTAG 16 emphasize data analytics in risk-based auditing.
Final Justification:IIA References:
* IPPF Standard 1220 - Due Professional Care
* IIA GTAG 16 - Data Analytics in Auditing
* COSO Framework - Data-Driven Risk Management

A major risk when upgrading an IT network after a ransomware incident is that new access controls, monitoring rules, security procedures, or user restrictions may be perceived as burdensome by employees. If users believe the new processes slow work or are overly restrictive, they may bypass controls, resist implementation, or fail to comply consistently. Option A relates to project governance, but the scenario focuses on operational and user impact of the network change. Option B is not a risk created by the change itself. Option D describes service-quality consequences but is less directly tied to the policy and control changes introduced after ransomware. Internal audit should review change management, user communication, training, access redesign, and control adoption. Therefore, Option C is correct.