Is it possible due to a short for a thermostat to change its setting? There are two people living in a small duplex and I noticed the all of the outlets are wired "upside down" and some of the light switches don't work properly. The thermostat has jumped up to 80 and down as low as 50 with no one physically changing it. It is not in a place that it can be easily "bumped" etc.

Please clarify what you mean by outlets being wired "upside down" - do you mean that hot and neutral leads are reversed? Or do you mean that the outlet is wired correctly but actually mounted upside down? If the latter it's not an isssue, and in fact in many applications outlets are purposefully installed that way. If the former, I'd have to wonder if the furnace is properly wired. Did this behavior just start happening recently? Also, when you say that the thernostat has "jumped" do you mean the setting changes on its own? If so, if this is a programmable thermostat perhaps the programming has been changed?