Suppose that you have two populations: - Population A: you do
not know the distribution, mean,...
Suppose that you have two populations: - Population A: you do
not know the distribution, mean, and the variance of the
population. - Population B: you do not know the distribution and
the mean of the population. But you know the variance of the
population. Now you want to build a %90 confidence level interval
for the mean of each population separately by sampling. What is the
difference between the methods you use for each population??
Suppose that we want to test the null hypothesis that the mean
of population 1 is...
Suppose that we want to test the null hypothesis that the mean
of population 1 is equal to the mean of population 2. We select a
random sample from population 1 and a random sample from population
2, and these two samples are independent. Circle the FALSE
statement.
A. We need to perform a two-sided test.
B. If we know the variance of each population, even if they are
different, we can use the Z test. That is, the test...
You are comparing two population means, say population A and
population B. By doing that, you...
You are comparing two population means, say population A and
population B. By doing that, you are calculating a 90% confidence
interval for the difference means for sample A and sample B. This
90% confidence interval yields μA -
μB = (-2.876, 5.398)
Based on this 90% confidence interval, a student concluded that
the mean of population A is more than the mean of population B.
True
False
Suppose you want to determine whether the average values for
populations 1 and 2 are different,...
Suppose you want to determine whether the average values for
populations 1 and 2 are different, and you
randomly gather the following data.
sample 1
2, 11, 7, 8, 2, 5, 9, 1, 9, 1, 5, 8, 11, 2, 5, 5, 6, 9
sample 2
10, 12, 8, 12, 9, 12, 9, 7, 9, 10, 11, 10, 11, 10, 7, 8, 10,
10
Test your conjecture, using a probability of committing a Type I
error of .01. Assume the population...
Suppose you have selected a random sample of ?=14 measurements
from a normal distribution. Compare the...
Suppose you have selected a random sample of ?=14 measurements
from a normal distribution. Compare the standard normal ? values
with the corresponding ? values if you were forming the following
confidence intervals.
(a) 90% confidence interval
z=
t=
(b) 95% confidence interval
z=
t=
(c) 98% confidence interval
?=
t=
2) A confidence interval for a population mean has length
20.
a) Determine the margin of error.
b) If the sample mean is 58.6, obtain the confidence
interval.
Confidence interval: ( ,...