researchers-are-studying-blood-lead-levels-in-two-groups-children-living-near-a-

Question

Researchers are studying blood lead levels in two groups: children living near a highway with $n equals 35$ , $x ˉ equals 8.2 mu g slash dL$ , and $s equals 3.9 mu g slash dL$ , and children living in rural areas with $n equals 35$ , $x ˉ equals 1.1 mu g slash dL$ , and $s equals 3.3 mu g slash dL$ . Suppose an $F$ test was used at the $0.05$ significance level to test the claim that the variation in blood lead levels is greater for children living near the highway than for those in rural areas. Also, the rural group data consists of the following values (in $μ g/dL$ ) : $2$ , $2$ , $12$ , $15$ , $6$ , and $30$ other values that are all $0$ .
Does this sample appear to be from a normally distributed population? If not, how does this affect the conclusion from the $F$ test?

Does this sample appear to be from a normally distributed population? If not, how does this affect the conclusion from the $F$ test?

Accepted Answer

No, the rural group does not appear to be from a normally distributed population. Thus, the results of the $n equals 35$ test may not be valid.

Answer

Yes, the rural group appears to be from a normally distributed population. Thus, the results of the $n equals 35$ test are valid.

Answer

No, the rural group does not appear to be from a normally distributed population. However, because both groups have the same sample size, the $n equals 35$ test is robust and the conclusion remains valid.

Answer

Yes, the rural group appears to be from a normally distributed population. However, because both groups have sample standard deviations that are less than $n equals 35$ , the results of the $F$ test may not be valid.