What are the processes of gentrification and filtering ? (in a geographical urban context)?

Question

What are the processes of gentrification and filtering ? (in a geographical urban context)?

Answer 1

Gentrification is the process by which urban renewal of a portion (of a city) is carried out by driving out middle and lower middle classes by offering such high price for their land that they wouldn't dream of. It implies change of gentry of and to higher levels. Filtering is, but not always, the reverse of it.