Forensic Systems Engineering

17Forensic Sampling of Internal Controls

CHAPTER MENU

1. 17.1 Populations
2. 17.1.1 Sample Population
3. 17.1.2 Homogeneity
4. 17.1.3 Population Size
5. 17.1.4 One Hundred Percent Inspection
6. 17.2 Sampling Plan
7. 17.2.1 Objectives
8. 17.2.2 Statistical and Nonstatistical Sampling
9. 17.2.3 Fixed Size and Stop‐or‐Go
10. 17.2.4 Sample Selection and Size
11. 17.3 Attribute Sampling
12. 17.3.1 Internal Control Sampling
13. 17.3.2 Deviation Rates
14. 17.3.2.1 Acceptable Deviation Rate
15. 17.3.2.2 System Deviation Rate
16. 17.3.3 Sampling Risks
17. 17.3.3.1 Control Risk
18. 17.3.3.2 Alpha and Beta Risks
19. 17.3.4 Confidence Level
20. 17.3.5 Evaluation
21. 17.4 Forensic System Caveats
22. References

In litigation concerning a performer’s operations, the forensic systems analyst will turn to discovery to gather evidence of the effectiveness of operational processes. The evidence will be an historical record of references, records of activities, reports, and of various associated data including emails. This information is bounded in time by the epoch in litigation. With respect to the forensics of operational systems, that evidence is relevant that refers to or is related to the conformity of internal controls to recognized good business practices and to contract requirements.

Some formal means of extraction and inspection of the evidence may be required if the analysis is to have integrity. The formal means will follow established legal procedures of discovery, but not all the data may be examined. The data may be sampled, which is a well‐defined discipline ...