Survey Concepts and Terminology

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Survey Concepts and Terminology
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NASS provides timely, accurate, useful statistics
in service to U.S. agriculture.

• Staff
• 1. NASDA about 3,500
• 2. NASS about 1,300 (includes both state and
  federal workers)

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Concepts and terminology used when discussing
surveys are

• Farm operator.
• Census.
• Sampling.
• List Frame.
• Area Frame.
• Multiple Frame.

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Farm operator Person responsible for
day-to-day decisions on land where annual sales
of agricultural products were or could be at
least 1,000.
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Census of Agriculture

• Every 5 years.
• Livestock inventories, acreage and production,
  economics, demographics.
• Mandatory participation by law.

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Sampling

• Surveys use sampling because
• Quicker.
• Cost efficient.

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Sample or All?

• What is your opinion?
• If your State has 50 known growers of a specialty
  crop, should a sample be drawn or should all be
  contacted?

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Sample or All?

• If your State has 50 known growers of a
  specialty crop should a sample be drawn or should
  all be contacted?
• Generally, if there are only 50 growers of a
  commodity then all should be contacted a census
  of the growers.

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Sampling Types

• There are two types of samples
• Probability
• Nonprobability

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Sampling Types - Probability

• The two types of samples
• Probability each farm operation represents
  others that are similar in size.
• Nonprobability arbitrarily add or delete
  respondents.

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Sampling Types - Nonprobability

• The two types of samples
• Probability each farm operation represents
  others that are similar in size.
• Nonprobability arbitrarily add or delete
  respondents.

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List Frame

• List Frame A list of names with captured survey
  data (for future sampling).

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Area Frame

• Area Frame Land segments representing your
  States land uses.

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Multiple Frame

• Multiple Frame List Area Frame
• Cost efficient.
• Area Frame compensates for incomplete List Frame

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Review

• Please answer the following question
• By definition, a farmer has to produce what value
  of agricultural goods each year?

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Review - Answer

• By definition, a farmer has to produce 1,000 of
  agricultural products each year. Sales do not
  have to actually occur.

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Review

• How often is the Census of Agriculture conducted?

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Review - Answer

• The Census of Agriculture is conducted every five
  years.

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Review

• What are two advantages of sampling respondents
  (instead of contacting everyone)?

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Review - Answer

• The two advantages of sampling respondents are
  that sampling is quicker and there is a cost
  savings.

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Review

• Why is the List Frame never completely accurate
  (farm operator names current)?

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Review - Answer

• The List Frame is never completely accurate
  because farm operators are constantly going out
  of business and entering farming.

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Summary

• Concepts and terminology you should now
  understand are
• Farm Operator.
• Census.
• Sampling.
• List Frame.
• Area Frame.
• Multiple Frames.