The available information are listed in Table 25. Table 25 Available information – Variable Value Intercept 0.70 North Price coefficient of demand function North -1.2 Price North (pounds kg) 0.10 Intercept South 11.50 Income coefficient South 0.01 Income South (000 pounds) 1.2 Demand function North Linear Demand function South Semilogarithmic Engel In this example there are two new elements. The former is how to use of logarithms in equation entry and the latter is the command DISPLAY. As illustrated in Table 7 at Par. 3.4.4, the notation for the logarithm is LOG(.) with dot in brackets the symbol of the parameter in Equation definition. As far as the comma Display is concerned, it specifies the type of output generated by the GAMS program. For this reason it is written after the SOLVE command. It is used to show the values of parameters and variables. The SYNTAX in the case we want to see two parameters and tow variables is: DISPLAY <parameter name>, <parameter name>, <variable name>.L, <variable name>.L; As noticed, for variables a specific notation must be added to the name; it is .L. The statement ends with a semicolon. The model is written in the following form. *GAMS model for different functional forms PARAMETERS A Intercept North B Price coefficient of demand function North P Price North
The available information are listed in Table 25. Table 25 – Available information Variable Value Intercept North 0.70 Price coefficient of demand function North -1.2 Price North (pounds kg) 0.10 Intercept South 11.50 Income coefficient South 0.01 Income South (000 pounds) 1.2 Demand function North Linear Demand function South Semilogarithmic Engel In this example there are two new elements. The former is how to use of logarithms in equation entry and the latter is the command DISPLAY. As illustrated in Table 7 at Par. 3.4.4, the notation for the logarithm is LOG(.) with dot in brackets the symbol of the parameter in Equation definition. As far as the comma Display is concerned, it specifies the type of output generated by the GAMS program. For this reason it is written after the SOLVE command. It is used to show the values of parameters and variables. The SYNTAX in the case we want to see two parameters and tow variables is: DISPLAY <parameter name>, <parameter name>, <variable name>.L, <variable name>.L; As noticed, for variables a specific notation must be added to the name; it is .L. The statement ends with a semicolon. The model is written in the following form. *GAMS model for different functional forms PARAMETERS A Intercept North B Price coefficient of demand function North P Price North
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