Beckmann;s interaction model has each resident touching base in face-to-face activity with every other resident, per unit time, at the other's residence. We re-work his resulting "interaction city" with each resident "operating with" a Cobb-Douglas utility function. We then turn to a more...

We consider a competitive extraction industry comprising many small firms, each with a slightly different quality of mineral holdings. With "rapidly" declining quality of holding per firm we observe rent declining over an interval. We then take up the familiar planning model and isolate the tax...