How to connect a bend sensor?
Its not exactly clear on which part number that is.  I'm guessing its something similiar to this:



This looks like a variable resistor.  That would mean, you apply voltage and read the drop across the sensor.  If your device has similar performance to the one in the attached chart, you might add a resistor (10K) in series.  Wire one end to +5v, the other end to ground, then measure the voltage in the middle (single wire to an analog input on the arduino)  

So my answer to your specific question is I don't think it makes any difference which side is which (anode/cathode behavior of that resistor shouldn't make any difference...)  But I would not wire it the way you are thinking.  

Have you checked the specification sheet for your specific device? (Hint: where did you get the part?  Manufacturer's name?  Manufacturers part number?)

Do you really need a voltage divider?  Its not always clear to me on pull up / pull down voltage sense on analog inputs. If I have +5v on one end and ground on the other I know exactly what is going on, I don't have to make assumptions about the inner workings of my input/output card...