search for: other_variables

...wise. How do I assign a zero to a city when it does not have an observation for that year? For example. Suppose I have the following data set. The observation range over three years 1990-1992. But some cities did not report in some years. The original data looks like this: Cicoid year other_variables seclection-variable 1 1990 x x x x x x x 1 1 1991 xxxxxxxxxx 1 2 1991 xxxxxxxxxx 1 3 1990 xxxxxxxxxx 1 3 1991 xx...

Hi, We are building a rails application that''s sort of a CRM + room/course booking. Among other things, it provides a centralized database of all the people the company has been in contact with. We want to provide the possibility of sending customized email messages to groups of contacts, for example a newsletter to 500 people starting with "Hi [:name:]". The naive approach