You'd get more specific info if you give more specific info. Is this the thingy youre asking about http://www.sparkfun.com/datasheets/Sensors/Flex/SoftPot-Datasheet.pdf
Can you give us a schematic? What do you n=mean by "floating value"? Got code?
A pot with voltage on one end and grounded on the other gives a voltage at the wiper linearly proportional to the wiper position, so long as there is no current or load..
If you add a fixed resistor from wiper to either end, then yes, the wiper voltage is no longer a linear function of position.