IAAO 101; FUNDAMENTALS OF PROPERTY
APPRAISAL AND ASSESSMENT
ADMINISTRATION Comprehensive
Certification Examination Study Guide
2026 WITH CORRECT ANSWERS AND IN-
DEPTH RATIONALES !
SECTION 1: MASS APPRAISAL PRINCIPLES AND CONCEPTS
1. What is the primary purpose of mass appraisal?
A) To appraise individual properties for mortgage lending
B) To value all properties within a jurisdiction fairly and uniformly for taxation
C) To determine insurance replacement costs
D) To establish listing prices for real estate agents
CORRECT ANSWER: B
Rationale: Mass appraisal is the process of valuing a universe of properties as of a given
date using standardized procedures and statistical testing to ensure fair and equitable
assessment for property taxation purposes.
2. Which of the following best defines "uniformity" in property assessment?
A) All properties being assessed at the same dollar amount
B) Properties with similar characteristics having similar assessed values
C) All properties being reassessed annually
D) Properties being assessed based on owner income
CORRECT ANSWER: B
,Rationale: Uniformity means that properties with similar physical and economic
characteristics are assessed at similar values, ensuring horizontal equity across the tax
base.
3. The coefficient of dispersion (COD) measures:
A) The average property value in a jurisdiction
B) The percentage change in property values from year to year
C) The average deviation of assessment ratios from the median
D) The total tax revenue collected
CORRECT ANSWER: C
Rationale: The COD is a statistical measure of assessment uniformity that calculates the
average absolute deviation of assessment ratios from the median, expressed as a
percentage.
4. What is the International Association of Assessing Officers (IAAO) standard for an
acceptable COD for residential properties?
A) Less than 5%
B) Less than 10%
C) Less than 15%
D) Less than 20%
CORRECT ANSWER: C
Rationale: IAAO standards recommend a COD of 15% or less for residential properties
and 20% or less for commercial/industrial properties to indicate acceptable assessment
uniformity.
5. The price-related differential (PRD) is used to measure:
A) Assessment regressivity or progressivity
B) Property value appreciation rates
C) Tax rate changes over time
,D) Building depreciation percentages
CORRECT ANSWER: A
Rationale: The PRD measures the relationship between assessment levels and property
values, indicating whether higher-valued properties are disproportionately under-
assessed (regressive) or over-assessed (progressive).
6. Which statistical measure indicates the central tendency of assessment ratios?
A) Standard deviation
B) Coefficient of dispersion
C) Median
D) Price-related differential
CORRECT ANSWER: C
Rationale: The median is the preferred measure of central tendency for assessment
ratios because it is less affected by extreme values than the mean.
7. What does a COD of 12% indicate about an assessment jurisdiction?
A) Poor uniformity requiring complete reassessment
B) Acceptable uniformity within IAAO standards
C) Unacceptable uniformity requiring immediate correction
D) Perfect uniformity with no deviations
CORRECT ANSWER: B
Rationale: A COD of 12% is within the IAAO standard of 15% or less for residential
properties, indicating good assessment uniformity.
8. Mass appraisal differs from single-property appraisal in that mass appraisal:
A) Is more accurate for individual properties
B) Uses standardized data and statistical models
, C) Requires less training for appraisers
D) Focuses only on residential properties
CORRECT ANSWER: B
Rationale: Mass appraisal uses standardized procedures, statistical models, and
computer-assisted techniques to value large numbers of properties consistently, while
single-property appraisal provides more detailed analysis for individual properties.
9. The primary standard for assessment ratio studies is:
A) ASTM E2018-15
B) USPAP Standard 6
C) ISO 9001
D) GAAP Standards
CORRECT ANSWER: B
Rationale: Uniform Standards of Professional Appraisal Practice (USPAP) Standard 6
specifically addresses mass appraisal and assessment ratio studies.
10. Which of the following is NOT a standard measure of assessment uniformity?
A) Coefficient of Dispersion (COD)
B) Coefficient of Variation (COV)
C) Price-Related Differential (PRD)
D) Gross Domestic Product (GDP)
CORRECT ANSWER: D
Rationale: GDP is an economic indicator of national output, not a measure of
assessment uniformity. COD, COV, and PRD are all statistical measures used in
assessment ratio studies.
11. In mass appraisal, "stratification" refers to:
APPRAISAL AND ASSESSMENT
ADMINISTRATION Comprehensive
Certification Examination Study Guide
2026 WITH CORRECT ANSWERS AND IN-
DEPTH RATIONALES !
SECTION 1: MASS APPRAISAL PRINCIPLES AND CONCEPTS
1. What is the primary purpose of mass appraisal?
A) To appraise individual properties for mortgage lending
B) To value all properties within a jurisdiction fairly and uniformly for taxation
C) To determine insurance replacement costs
D) To establish listing prices for real estate agents
CORRECT ANSWER: B
Rationale: Mass appraisal is the process of valuing a universe of properties as of a given
date using standardized procedures and statistical testing to ensure fair and equitable
assessment for property taxation purposes.
2. Which of the following best defines "uniformity" in property assessment?
A) All properties being assessed at the same dollar amount
B) Properties with similar characteristics having similar assessed values
C) All properties being reassessed annually
D) Properties being assessed based on owner income
CORRECT ANSWER: B
,Rationale: Uniformity means that properties with similar physical and economic
characteristics are assessed at similar values, ensuring horizontal equity across the tax
base.
3. The coefficient of dispersion (COD) measures:
A) The average property value in a jurisdiction
B) The percentage change in property values from year to year
C) The average deviation of assessment ratios from the median
D) The total tax revenue collected
CORRECT ANSWER: C
Rationale: The COD is a statistical measure of assessment uniformity that calculates the
average absolute deviation of assessment ratios from the median, expressed as a
percentage.
4. What is the International Association of Assessing Officers (IAAO) standard for an
acceptable COD for residential properties?
A) Less than 5%
B) Less than 10%
C) Less than 15%
D) Less than 20%
CORRECT ANSWER: C
Rationale: IAAO standards recommend a COD of 15% or less for residential properties
and 20% or less for commercial/industrial properties to indicate acceptable assessment
uniformity.
5. The price-related differential (PRD) is used to measure:
A) Assessment regressivity or progressivity
B) Property value appreciation rates
C) Tax rate changes over time
,D) Building depreciation percentages
CORRECT ANSWER: A
Rationale: The PRD measures the relationship between assessment levels and property
values, indicating whether higher-valued properties are disproportionately under-
assessed (regressive) or over-assessed (progressive).
6. Which statistical measure indicates the central tendency of assessment ratios?
A) Standard deviation
B) Coefficient of dispersion
C) Median
D) Price-related differential
CORRECT ANSWER: C
Rationale: The median is the preferred measure of central tendency for assessment
ratios because it is less affected by extreme values than the mean.
7. What does a COD of 12% indicate about an assessment jurisdiction?
A) Poor uniformity requiring complete reassessment
B) Acceptable uniformity within IAAO standards
C) Unacceptable uniformity requiring immediate correction
D) Perfect uniformity with no deviations
CORRECT ANSWER: B
Rationale: A COD of 12% is within the IAAO standard of 15% or less for residential
properties, indicating good assessment uniformity.
8. Mass appraisal differs from single-property appraisal in that mass appraisal:
A) Is more accurate for individual properties
B) Uses standardized data and statistical models
, C) Requires less training for appraisers
D) Focuses only on residential properties
CORRECT ANSWER: B
Rationale: Mass appraisal uses standardized procedures, statistical models, and
computer-assisted techniques to value large numbers of properties consistently, while
single-property appraisal provides more detailed analysis for individual properties.
9. The primary standard for assessment ratio studies is:
A) ASTM E2018-15
B) USPAP Standard 6
C) ISO 9001
D) GAAP Standards
CORRECT ANSWER: B
Rationale: Uniform Standards of Professional Appraisal Practice (USPAP) Standard 6
specifically addresses mass appraisal and assessment ratio studies.
10. Which of the following is NOT a standard measure of assessment uniformity?
A) Coefficient of Dispersion (COD)
B) Coefficient of Variation (COV)
C) Price-Related Differential (PRD)
D) Gross Domestic Product (GDP)
CORRECT ANSWER: D
Rationale: GDP is an economic indicator of national output, not a measure of
assessment uniformity. COD, COV, and PRD are all statistical measures used in
assessment ratio studies.
11. In mass appraisal, "stratification" refers to:
