Who were the two major native american groups in the new york state region? what type of houses did they live in

The two major Native American groups in the New York State region were the Mohawk and the Seneca tribes - both part of the Iroquois. They lived in longhouses.

An informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.