Examples - Decomposing a Formula

In ORANIG, the formula for calculating the value of household purchases of commodity c from source s (domestic or imported) valued at purchasers’ prices is

(All,c,COM)(All,s,SRC) V3PUR(c,s) =

V3BAS(c,s) + V3TAX(c,s) + SUM(m,MAR, V3MAR(c,s,m) ) ;

You can ask AnalyseGE to decompose the right-hand side of this. [To do so, first click somewhere in this formula. Then right click and choose menu item Decompose RHS of this Formula - toggle first.]

When you decompose the RHS of a Formula, you get an intelligent decomposition - that is, a decomposition which respects brackets and SUMs.

The decomposition will show, in the ViewHAR form, a coefficient TempCoeff with 3 arguments. The first argument ranges over the "toggle" set whose elements are V3BAS, V3TAX and e1_V3MAR. The second and third arguments range over the sets COM and SRC. For each c in COM and s in SRC,

· the values of TempCoeff("V3BAS",c,s) show the values of V3BAS(c,s),

· the values of TempCoeff("V3TAX",c,s) show the values of V3TAX(c,s), and

· the values of TempCoeff("e1_V3MAR",c,s) show the values of SUM(m,MAR,C3MAR(c,s,m)).

This enables you to see very easily how much these three parts of data contribute to the V3PUR(c,s) values. [For example, you can easily show appropriate shares in the ViewHAR form.]

The general idea of "toggles" is introduced elsewhere. You can choose to put the toggle set first or last (which affects how the results appear in ViewHAR). AnalyseGE makes up toggle names (for example, "V3BAS", "V3TAX" and "e1_V3MAR" above) based on the names of the Coefficients in the different expressions.

Exactly What Are You Seeing?

As with all decompositions, if you are at all unsure exactly what values you are seeing in each toggle, you can look at the Exxx header on the ViewHAR form or in the Evaluate memo on the AnalyseGE form.

URL of this topic: www.copsmodels.com/webhelp/analysege/hc_decompform.htm

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