Evaluating Publication Rules for the 

County Agricultural Production 

Survey Using Simulation

Andrew J. Dau, Nathan B. Cruze, Joe L. Parsons, and Linda J. Young 

USDA/NASS

1
Disclaimer

• The findings and conclusions in this presentation are those of 

the author and should not be construed to represent any 

official USDA or U.S. Government determination or policy.

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County Agricultural Production Survey

• Annual Survey

– Small Grains

– Row Crops

• Publication of county level estimates of planted and harvested acreage –

yield and production

• 2019 and earlier publication rule:

– 30 reports 

OR

– 3+ reports AND >= 25% coverage.

3
Goals/Objectives

• Publish accurate estimates

• Publish as much as possible

4
Administrative Data

• USDA program

• Excellent Coverage

• For this simulation, treating as the population.

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Monte Carlo Simulation

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US Level Dataset County Level 

Data

n=5

1000x

n = 3

1000x

n=10

1000x

n=30

1000x

n=20

1000x
Simulation Design

• Probability Proportionate to Size (PPS)

• Weighted Yield (Ratio Production/Acres)

• Variance Estimated

• Coefficient of Variation Calculated

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Pennsylvania County Example

Coefficient of Variation (CV)

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Pennsylvania County Example

Yield

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Low CV &

Far From Truth

• What is a さlowざ CV?

– For this example, we will use 20%

• What is さfarざ froマ populatioミ paraマeter?

– For this example, we will use 5 bushels/acre

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Pennsylvania County Example

n=3 

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Pennsylvania County Example

difference, coverage, cv, and sample size

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Pennsylvania County Example

Old Publication Rule

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Expanding

• For visualization purposes

– 20 random counties

– 10 different states

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15

20 Counties

Difference, Coverage, CV, and Sample size
20 Counties

Old Publication Standard

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20 Counties

Old Publication Standard – Not Published

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20 Counties

old publication standard

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20 Counties

Old PuHliIatioミ “taミdard = さYesざ

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A new standard

• 30 reports 

OR

• 3 reports and 25% coverage 

OR

• 10 reports and 10% coverage ***new***

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21

20 Counties

New Publication Standard
Old vs New

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Old 

Publication 

Standard

New 

Publication 

Standard
Old vs New

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Old 

Publication 

Standard

New 

Publication 

Standard
New Publication Standard

Simulation estimates published under new standard, but not old

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Summary

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Pub Rule

Total 

Simulations

Number 

Published

Number 

Published With 

Greater than 5 

Bushels/Acre 

from Population

Good Pub Rate 

(% published 

within 5 

bushels/acre of 

Population)

Absolute 

Average 

Difference from 

Population 

bushels/acre

Old Rule 100,000 30,869 9,458 0.69 4.09

Proposed Rule 100,000 46,583 16,453 0.65 4.57

CV < 20% 100,000 98,268 50,313 0.49 12.02
Additional Factors

• County Agricultural Production Survey modeled indications

– Cruze et all (Statistical Science 2019 vol 34)

– Strength added to yield indication from National Commodity Crop 

Productivity Index (NCCPI) and location

• Additional References

– Bell and Barboza (2012) ICES proceedings

– Cruze et al (2018) JSM proceedings

– Cruze and Young (2019) JSM proceedings

– National Academies Report (2017)

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Conclusion

• One size fits all is difficult

• Simulation allows for a variety of different rules to be explored. 

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