A draft protection device for a balance and a balance equipped with the draft protection device, wherein the draft protection device includes front and rear panels, two side panels and a top panel, and four posts which are fixedly mounted on a top cover of the balance, and wherein the posts extend vertically. The core may be a foam material such as a polystyrene foam or a polyethylene foam. Accordingly, a request to initiate a chat cluster is received from a user. User reputation scores are determined based at least in part on the graph.