Elmhurst is located in northeast Illinois. Elmhurst is between the Dupage, Cook county. Elmhurst has 10.25 square miles of land area and 0.06 square miles of water area. As of 2010, the total Elmhurst population is 44,121, which has grown 3.18% since 2000. The population growth rate is about the same as the state average rate of 3.31% and is much lower than the national average rate of 9.71%. Elmhurst median household income is $94,424 in 2008-2012 and has grown by 35.29% since 2000. The income growth rate is much higher than the state average rate of 22.03% and is higher than the national average rate of 26.32%. Elmhurst median house value is $377,200 in 2008-2012 and has grown by 78.68% since 2000.
The independent t-test assumes the variances of the two groups you are measuring to be equal. If your variances are unequal, this can affect the Type I error rate.
The variance of a random variable X {\displaystyle X} is the expected value of the squared deviation from the mean of X {\displaystyle X} , Î¼ = E â¡ [ X ] {\displaystyle \mu =\operatorname {E} [X]} : This definition encompasses random variables that are generated by processes that are discrete, continuous, neither, or mixed.