IOkertojen

IOkertojen is a term used in economic analysis to refer to the matrix of input–output coefficients that link the outputs of different sectors to the inputs they require. In Finnish-language discussions, IOkertojen describe how much input from each sector is needed to produce one unit of output in another sector, forming the core of the Leontief input–output framework.

Mathematically, the IOkertojen are organized as a matrix A with elements a_ij, where a_ij represents the amount of input from sector i required per unit of output in sector j. The relationships in an economy are expressed as x = Ax + f, where x is the vector of gross outputs by sector and f is the vector of final demand. The total input requirements implied by final demand are given by the Leontief inverse (I − A)^{-1} f, which shows the full production impact across all sectors, including indirect effects.

Calculation and interpretation: each column j of A shows the direct inputs from all sectors needed for one unit of output in sector j. The entries convey how technology and interindustry linkages drive production, while the inverse matrix captures multipliers that translate final demand changes into total output changes across the economy. IOkertojen thus enable scenario analysis, policy assessment, and supply-chain planning by quantifying direct and indirect production requirements.

Limitations and context: the IOkertojen approach assumes linear, fixed technology with constant coefficients, ignores price changes, and is sensitive to data quality and timing. It is most informative for mid-term, structural analysis rather than short-term dynamics.

See also: Leontief input–output model, input–output analysis, economic multipliers.