Mod 7 Audit Sampling Key Concepts Flashcards
If your testing but not projecting…
That’s not sampling
Sampling (3 part definition)
1 taking part of the population
2 doing some audit tests
3 then projecting the results
A sample represents the population…
When it is drawn randomly
Sampling risk
Risk that sample does not represent the population
Nonsampling risk
Risk of human error
Risk of assessing control risk too low
Overreliance on internal controls
by raising detection risk and performing less substantive tests
For the Risk of assessing control risk too low, what is sacrificed?
Effectiveness
Risk of assessing control risk too low doesn’t mean…
2) but…
Doesn’t mean financial statements are misstated
2) but there’s a high risk that they are
Risk of assessing control risk to high…
Under reliance (on internal controls)
Perform more work than needed
What does the Risk of assessing control risk to high sacrifice?
Efficiency
Efficiency
Quickly
Effectiveness
Reach the right conclusion
Incorrect acceptance
Auditor incorrectly concludes $ amount is fairly stated
Incorrect acceptance sacrificed…
Effectiveness
Incorrect rejection
Auditor incorrectly concludes $ amount is not fairly stated
Incorrect rejection sacrificed…
Efficiency
Sacrificing effectiveness can effect…
Outcome of your opinion on financial statements
What are 2 other terms with the same meaning as “error”
1 exception
2 deviation
Error, exception, deviation mean that…
2) example 2
Something is not coming out the way it should
2) shipping documents are not billed or are billed for incorrect
Amount
Attribute sampling
Looking at control procedures
To see whether it’s operating effectively or it’s not
Nonstatistical sampling involves more…
Judgement
Tolerable rate
Error rate in population auditor’s willing to live with
Tolerable rate involves…
Judgement
The term “rate” is…
Always used in testing a control procedure (not a $ amount)
Example of a rate
Shipping documents that aren’t billed properly
If 3 aren’t billed properly from a sample of 100, the rate is 3 %
Expected population error rate
What error rate the auditor thinks exists based on past experience
Risk of assessing control risk too low is part of…
Attribute sampling
Relation of tolerable rate to sample size
2) what does this mean?
Inverse
2) If you can tolerate higher error rate in population, sample size
Can be smaller
Relation of expected population error rate to sample size
2) what does this mean?
Direct
2) if you think there is a higher error rate in the population, you need
A bigger sample size
Relation of risk of assessing control risk too low to sample size
2) what does this mean?
Inverse
2) if you’re going to assess control risk too low, to assess it higher
You can get away with a smaller sample size
If you want to go from a confidence interval of 90% to 95%, you need…
A bigger sample size
Compliment confidence interval, how is it calculated if confidence interval is 95%?
If confidence interval = 95%
The compliment confidence interval = 5% = (1 - 95%)
What is the equation for tolerable error rate?
Sample error rate + allowance for sample risk < or = tolerable error rate
Example of sample error rate
Tested 100 documents and found 5 not billed
So sample error rate = 5%
Allowance for sampling risk is determined…
As a judgement of the auditor
If sample error rate + allowance for sampling risk is greater than the tolerable error rate
Controls are not operating effectively
If sample error rate + allowance for sampling risk is less than or equal to the tolerable error rate then…
Controls are operating effectively
6 steps of sample planning
1 determine objective of test 2 define your population 3 determine the sample size 4 select the sampling technique 5 perform sampling plan 6 evaluate results/document
1 determine objective of test 2 define your population 3 determine the sample size 4 select the sampling technique Are all part of...
Planning in the sample plan
Sample plan:
1) determine objective of test example
Want to see if shipments have been billed
Sample plan:
Define your population and deviation example
Population = shipping documents
Deviation = shipments not billed
Sample plan:
Determine the sample size
Use statistical or nonstatistical sampling
Sample plan:
Select the sampling technique example 2
1 random number generator
2 every nth item
Randomly
Every item in population has an equal chance to get into the sample
Systematic sampling
Every nth item
Systematic sampling (every nth item) is random because…
It’s a random start
Discovery sampling, main objective
Ex.
Wants to virtually assure sample finds errors in population
Ex. Want to find phony employees on the payroll
Variables sampling involves…
$ amounts
Higher confidence level
Higher level of assurance that sample represents the population
Relation of confidence interval to sample size
What does this mean?
Direct
2) to obtain a higher level of assurance that the sample represents
the population, you need a bigger sample size
Precision
+ or - range
Ex. 100 + or - 3, 3 is the precision
Relation of precision to sample size
What does this mean?
Direct
2) if you want to be more precise you need a larger sample size
Relation of variability in the population to sample size
Direct
Relation of tolerable misstatement to sample size
What does this mean?
Inverse
2) if you can tolerate higher tolerable misstatement, your sample
Size can be smaller
Projected misstatement:
Logical unit less than sampling interval, equation
Projected misstatement =
Percentage of account misstated x sampling interval
Projected misstatement:
Percentage of account misstated AKA “taint” calculation
% of account misstated = misstatement/book value
Projected misstatement:
Logical unit greater than sampling interval
Actual amount of misstatement is considered to be projected misstatement
Classical variables sampling uses…
Normal distribution theory (standard deviations) to evaluate
Selected characteristics of the population
Variations of classical variables sampling:
Mean per unit method, Estimated Total Audited Value Calculation (ETAV)
ETAV = population size x average audited value
ETAV
Estimated total audited value
Variations of classical variables sampling:
Mean per unit method, projected misstatement calculation
Projected misstatement =
Population BV - estimated total audited value (ETAV)
Variations of classical variables sampling:
Difference Estimation Method, calculate average difference in sample
2) calculate projected misstatement
Average difference (in sample) = avg. BV - avg. audited value (AV)
2) projected misstatement = population size x avg. difference (sample)
Variations of classical variables sampling:
Difference Estimation Method, calculate Estimated total audited value (ETAV), assuming an overstatement has occurred.
ETAV = Population BV - projected misstatement (overstatement)
Variations of classical variables sampling:
Ratio Estimation Method, calculate estimated total audited value (ETAV)
ETAV = (Sample Avg. AV/Sample Avg. BV) x Population BV
Example of population BV
Total book value of accounts in population
Variations of classical variables sampling:
Ratio Estimation Method, calculate Projected Misstatement
Projected Misstatement =
Population BV - estimated total audited value (ETAV)
advantages of Probability proportional to size (PPS) sampling:
Generally…
Easier to use
advantages of Probability proportional to size (PPS) sampling:
Size of sample…
Not based on variation of audited amounts
advantages of Probability proportional to size (PPS) sampling:
Automatically…
Results in stratified sample
advantages of Probability proportional to size (PPS) sampling:
Individually…
Significant items are automatically identified
advantages of Probability proportional to size (PPS) sampling:
Usually results in a…
Smaller sample size if no misstatements are expected
advantages of Probability proportional to size (PPS) sampling:
Can be easily designed and…
Sample selection can begin before the complete population
Is available
advantages of classical variables sampling:
May result in a smaller sample size if…
There are many differences between audited and book values
advantages of classical variables sampling:
Easier to expand…
Sample size if that becomes necessary
advantages of classical variables sampling:
Selection of zero balances…
Does not require special sample design considerations
Inclusion of negative balances does…
Not require special sample design considerations