Median real estate property taxes paid for housing units with mortgages in 2013: $590 (1.2%). Median real estate property taxes paid for housing units with no mortgage in 2013: $637 (1.5%). Nearest city with pop. 50,000+: Bismarck, ND (78.6 miles, pop. 55,532). Nearest city with pop. 200,000+: Minneapolis, MN (305.7 miles, pop. 382,618).
The third type of variable is a controlled variable. This variable is constant in an experiment. Experiments are repeated a number of times to interpret how a change in the independent variable affects each trial result.
In this function, y is the dependent variable and x is the independent variable. Variable used in an experiment or modelling can be divided into three types:  dependent variable ,  independent variable , or other. The dependent variable represents the output or effect, or is tested to see if it is the effect. The independent variable represents the input or cause, or is tested to see if it is the cause. Other variables may also be observed for various reasons.