# Research question formation

I am in the process of starting a research paper (for those in the IB Board, this is the Extended Essay) and I had previously formed my research question like this:

To what extent will factor x impact the economic growth and development of country y.

But then I thought I should narrow it down more so I made it:

To what extent will factor x impact the economic growth and development of city y.

I want to know if it's valid to talk about the economic growth and development of a city instead of a country. I have this confusion because I have never read the analysis of the economic growth and development of a city.

I mean development on a city basis is usually considered, but will looking at these macro concepts (growth and development) be viable for an economics research paper?

If yes, when I talk about growth, do I talk about the increase in AD/GDP or the increase in government revenue for city y etc?

However, it is not possible to give more specific answer without knowing what $$x$$ is. There is no guarantee that something that determines growth of an economy as a whole will be also important determinant at municipal level and vice versa.