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From |
"Sven P. Jost" <svenpjost@googlemail.com> |

To |
statalist@hsphsun2.harvard.edu |

Subject |
st: Constructing a variable: sum of a var over all j's (if j does not equal i) |

Date |
Fri, 6 Nov 2009 10:04:24 +0100 |

Hello everybody, I am currently experiencing a problem with the construction of a variable. Please consider the following: There are multiple cars in a city i. Further consider that the number of cars in city i depends on a weighted measure as given on the right hand side below (whereas i does not equal j)): Cars in city i = ... + SUM of [ (Cars in city j / Cars in all cities) x car dealers in city j ] over all j's. Please note that there is a variable car_loc indicating that a car is registered in a specific city. We are now interested in constructed the variable on the right hand side which, as far as I can tell, consists of three parts : (i) the sum of all cars in cities j (ii) the sum of cars in all cities (iii) and the sum of gas stations in cities j. Thank you for all your help in advance. Regards, Sven * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/

**Follow-Ups**:**st: AW: Constructing a variable: sum of a var over all j's (if j does not equal i)***From:*"Martin Weiss" <martin.weiss1@gmx.de>

**st: AW: Constructing a variable: sum of a var over all j's (if j does not equal i)***From:*"Martin Weiss" <martin.weiss1@gmx.de>

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