Question

Neuroinvasive West Nile virus refers to a severe disease that affects a person’s nervous system. It is spread by the Culex species of mosquito. In the United States in 2010 there were 629 reported cases of neuroinvasive West Nile virus out of a total of 1021 reported cases, and there were 486 neuroinvasive reported cases out of a total of 712 cases reported in 2011. Can we conclude that the 2011 proportion of neuroinvasive West Nile virus cases is significantly more than the 2010 proportion of neuroinvasive West Nile virus cases? If you conduct hypothesis testing, you have to consider:

Group of answer choices

a test of two proportions

a test of two independent means

a test of a single mean

a test of a single proportion.

Answer 1

For the yer 2010

n1 = 1021, x1 = 629, = 629/1021 = 0.6161

For the yer 2011

n2 = 712, x2 = 486, = 486/712 = 0.6826

We will use- A TEST OF TWO PROPORTION

Null Hypothesis, H0: =

Alternate Hypothesis, HA :   <

Test stattistics=

   = = 0.6434

Test statistic= = - 2.84

Critical value, Z (0.05) = -1.6449

Since the test statistic lie in the critical region , we reject the null hypothesis

So, there are sufficient evidence that the claim is correct.