Documentation
Scope of
Database
The database contains a collection of demand
elasticities-expenditure, income, own price, and cross
price-for a range of commodities and food products for over 100
countries.
Two ERS reports-International Evidence on Food Consumption
Patterns and International
Evidence on Food Consumption Patterns: An Update Using 2005
International Comparison Program Data-and their accompanying
data set, International Food
Consumption Patterns, account for almost all of the countries
in the database but not many of the elasticities. Most of the
elasticities are from studies on the United States and China.
Elasticities for fruits, vegetables, meats, grains, oilseeds,
and some processed foods are in the database. The greatest number
of demand studies are for vegetables, fruits, and grocery products
such as coffee and ketchup. Like the country coverage, the extent
of the commodity coverage is from International Food
Consumption Patterns, which estimates price and income
elasticities for eight food groups: bread and cereals, meat, fish,
dairy products, fats and oils, fruit and vegetables, beverages and
tobacco, and other food products.
Literature Sources
Most of the demand elasticities in the database are from
academic and government research conducted in the United States on
consumer demand, as published in working papers, dissertations, and
peer-reviewed journals and as presented at professional conferences
in the United States. To ensure proper citation of these sources,
bibliographic information is provided for each elasticity presented
in the Demand Elasticities from Literature Results. Information
includes the author(s), full journal citation, title of the source
table, and publication date.
See Citation List for a complete list of studies
in the database. Citations are listed alphabetically by the last
name of the lead author.
Search
Results
Users can query the
literature in the database for own- and cross-price, income, and
expenditure elasticities for specific commodities and
countries.
After a query has been submitted, a results table will be
displayed. In addition to elasticity estimates, supporting
details-such as the author, publication date, time period covered
by the research, model used, functional form, and model
properties-are also presented. Some of the results (columns with
titles in blue) can be sorted and ranked (see How To Use
the Database for details). Information on the model used, its
functional form, and its properties are provided to give users some
context for the reported elasticities.
Model Used
The most common demand models in the literature review are
Double-Log, Translog, the Rotterdam Model, Linear Expenditure
System (LES), and Almost Ideal Demand System (AIDS). See Commodity Elasticity
Models in the Glossary for a short explanation.
Model Functional Form
Consumer demand models generally have the following functional
forms: Hicksian or Compensated; Marshallian, Ordinary, or
Uncompensated; Conditional; or Unconditional. The functional forms
model consumer behavior to determine the quantity of goods
consumers are willing or able to purchase (the dependent variable)
given changes in prices or consumer incomes (the independent
variables). See Demand
Functions in the Glossary for a short explanation.
Model Properties
For each study in database, the demand properties reported in
the results table are homogeneity, additivity, symmetry, and
negativity when satisfied by that particular demand study. Demand
models exhibit specific theoretical properties based on the
assumptions used to derive the functions. For example, Marshallian
demand properties include additivity and homogeneity, while
Hicksian demand properties include additivity, homogeneity,
negativity, and symmetry. See Demand Properties in the Glossary for a short
explanation.
Statistical Information
Below the large results table is a smaller table containing
summary statistical information-minimum, maximum, mean, and
standard deviation-for the elasticities in the results table. For
example, a summary would look like this:
Reporting
Errors
If you find an error in the database, please notify the contacts
below. Please specify the exact location and item in the database
that needs to be corrected.
Download the Data
To download all of the demand elasticities in database, click on
the link below below.
- Demand
Elasticities from Literature. Each row in the
file contains an individual elasticity and its related study
information: citation, country, type of data, data period, citation
table number and name, model properties, major and minor
commodities, elasticity type, and significance level. File
format and size:
5.3 MB.
(Last updated, February 2006)