Symmetric Input-Output Tables
Definition
Symmetric Input-Output Tables are a quantitative means of presenting a detailed analysis of the process of production and the use of goods and services (products) and the income generated in that production.
Symmetric input-output tables are derived from the data in supply and use tables and other additional sources to form the theoretical basis for subsequent analyses.
These tables contain symmetric (product by product or industry by industry) tables, the Leontief Inverse Matrix and other diagnostic analyses such as output multipliers. These tables show separately the consumption of domestically produced and imported goods and services, providing a theoretical framework for further structural analysis of the economy, including the composition as well as the effect of changes in final demand on the economy. The symmetrical industry-by-industry IO tables show inter-industry transactions. They show all purchases an industry makes from all other industries.
Derivation
Symmetrical IO tables are analytically derived from the industry by product supply and use tables, which are part of the national accounts statistics.
Using various assumptions about technology, symmetric Input-Output tables can be derived from Supply and Use tables in basic prices. Symmetric tables can be constructed on product-by-product type or an industry-by-industry basis.
An industry-by-industry IOT essentially maps the purchases and sales of each industry sector to and from all other industry sectors. A product-by-product IOT maps in monetary terms how which products are used to produce a specific product.
Alternatively, product-by-product IO tables are compiled and provided.
The product-by-product tables show flows of final and intermediate goods and services defined according to product outputs.
Issues and Challenges
- The name Symmetric is a misnomer in mathematical sense. These tables are not symmetric (equal to their transpose). The proper name is "square" (they have equal number of rows and columns)
