About Custom Regions
I-JEDI is customizable and can be used to model potential economic impacts within regions for which there is not default data. In order to facilitate this a base set of input-output data has been compiled and uploaded for a number of countries, available from the drop-down menu below.
This core set of data can be used to estimate earnings, value added (GDP), and gross output. It consists of two vectors and two matrices:
- Value added per unit of output vector
- Earnings per unit of output vector
- Type one total requirements matrix
- Type two (includes household expenditures) total requirements matrix
Because of data availability I-JEDI does not include earnings per job for these additional countries, which is necessary to estimate employment impacts. If you do have this information you can estimate job impacts. If the country you are interested in is available from the above menu, select it, download the compiled data, and insert it into the custom region tab in the Excel-based I-JEDI model that matches your industry aggregation scheme. Alternatively, NREL may be able to incorporate this information into i-jedi.org. If you prefer this please e-mail firstname.lastname@example.org to evaluate options.
I-JEDI can be used for countries beyond those in the dropdown menu above. If you have the input-output data vectors and matrices listed above and (optionally) earnings per job you can insert this into the appropriate custom region tab of the Excel-based model. You can also e-mail email@example.com to evaluate options for uploading it to the online model.
Completing Custom Region Data Files
Custom Region files can be filled out and used in the Excel-based version of I-JEDI [link]. There are two ways of doing this. One is if the base input-output data is available from i-jedi.org, the other is if you obtained it from a different source.
Input-Output data available from i-jedi.org
If input-output data is available from i-jedi.org it can be downloaded and inserted into the Excel-based model. Data downloaded from i-jedi.org is in the same format as the Excel model and can simply be copied and pasted into the Excel model.
The dollar year of the data downloaded from i-jedi.org does not matter since the only vector that is dependent on the dollar year is the earnings per job vector.
The Excel-based version of I-JEDI does have a spot to enter average earnings per job. If you do have this data you can paste this into the model and subsequently be able to estimate job impacts. You will need to enter the dollar year of your earnings data.
Input-Output data not available from i-jedi.org
Input-output, or social accounting, data is widely available from a number of different sources so it is possible that you would like to use data not available from i-jedi.org. In this case you will need to process your own data. More information about how to do this is available in the I-JEDI user guide, including the linear algebra.
You will need to format your data the same what that the Custom Region worksheets in the Excel model are formatted. Choose the industry list that best aligns with your data set. You can aggregate industries within social accounting matrices by adding rows and columns. Custom Region 2 provides the highest level of aggregation and thus the greatest compatibility with other datasets.
Algebra to generate custom region data
Typically the data available is in the format of a social accounting matrix (SAM), which shows the levels of interactions between industries, households, investors, governments, and the rest of the world. Let this matrix be represented as Z. Let output be n·1 vector x. Variables with a ^ represent a square n·n matrix of zeroes with the indicated vector on the diagonal.
Value added as a portion of output (V) and earnings as a proportion of output (E) can be represented as:
Where G represents value added levels and L represents earnings levels.
Generation of the type 1 and type 2 total requirements matrices requires estimation of the direct requirements matrix (A). The type 1 total requirements matrix solely includes industries while the type 2 matrix includes industries as well as household expenditures and earnings. The Z matrix and resulting A matrix, then, will be differently sized. The Z and A matrices used to generate type 2 total requirements are n·n while the type 2 matrices are (n+1)·(n+1).
The A matrices can be estimated using:
The type 1 and type 2 total requirements matrices are (I-A)-1.
Default cost and local content data
While I-JEDI can be used to estimate impacts from countries other than its core set, I-JEDI does not contain default cost or local content data for these countries. This information will need to be entered in order to produce economic impact estimates.
This information is often available from developers, utilities, trade publications, individuals who are familiar with various technologies within your region of interest, or other publications that monitor energy costs and trends.