Question
In: Statistics and Probability
Independent random sampling from two normally distributed populations gives the results below. Construct a 95 %...
Independent random sampling from two normally distributed populations gives the results below. Construct a 95 % confidence interval estimate of the difference between the means of the two populations. η1 ¬= 82 (X_1 ) ̅ = 115 σ1 = 20 η2 = 83 (X_2 ) ̅ = 100 σ2 = 15
Solutions
Expert Solution
95% confidence interval for 
1 - 2 is
(
1 -
2) - Z *
sqrt [ 
1 / n2
+ 2 / n2
] < 1 - 2 <
(1 -
2) + Z *
sqrt [ 1 / n2
+ 2 / n2
]
(115-100) - 1.96 * sqrt [ 202 / 82 + 152 /
83) < 1 - 2 < (115-100)
+ 1.96 * sqrt [ 202 / 82 + 152 / 83)
9.601 < 1 - 2 <
20.399
95% CI is ( 9.601 , 20.399 )
orchestra answered 1 year agoRelated Solutions
Provided below are summary statistics for independent simple random samples from two normally-distributed populations. Conduct the...
Provided below are summary statistics for independent simple
random samples from two normally-distributed populations. Conduct
the required hypothesis test and obtain the specified confidence
interval.
xbar=12, s1=2.4, n1=20, xbar2=11, s2=7, n2=15
a) Right-tailed test, a=0.05. Find the test statistic. Find the
p-value
b) 90% confidence interval. Find the confidence interval
The following observations are from two independent random samples, drawn from normally distributed populations. Sample 1...
The following observations are from two independent random
samples, drawn from normally distributed populations.
Sample 1
[66.73, 66.8, 75.06, 58.09, 54.64, 52.83]
Sample 2
[66.71, 68.17, 66.22, 66.8, 68.81]
Test the null hypothesis H0:σ21=σ22 against the alternative
hypothesis HA:σ21≠σ22.
a) Using the larger sample variance in the numerator, calculate
the F test statistic.
Round your response to at least 3 decimal places.
b) The p-value falls within which one of the following
ranges:
p-value > 0.50
0.10 < p-value...
Assume that the two samples are independent simple random samples selected from normally distributed populations. Do...
Assume that the two samples are independent simple random
samples selected from normally distributed populations. Do not
assume that the population standard deviations are equal. Refer to
the accompanying data set. Use a 0.01 significance level to test
the claim that the sample of home voltages and the sample of
generator voltages are from populations with the same mean. If
there is a statistically significant difference, does that
difference have practical significance?
Day Home (volts) Generator
(volts)
1 123.7 ...
Assume that the two samples are independent simple random samples selected from normally distributed populations. Do...
Assume that the two samples are independent simple random
samples selected from normally distributed populations. Do not
assume that the population standard deviations are equal.
Refer to the accompanying data set. Use a 0.05 significance
level to test the claim that the sample of home voltages and the
sample of generator voltages are from populations with the same
mean. If there is a statistically significant difference, does
that difference have practical significance?
Day
Home( volts)
Generator( volts)
Day
Home (volts)...
Assume that two samples are independent simple random samples selected from normally distributed populations. Do not...
Assume that two samples are independent simple random samples
selected from normally distributed populations. Do not assume that
the population standard deviations are equal.
A paint manufacturer wished to compare the drying times of two
different types of paint. Independent simple random samples of 11
cans of type A and 14 cans of type B were selected and applied to
similar surfaces. The drying times, in hours, were recorded.
The summary statistics are below.
Type A:
x1 = 75.7
hours,...
Assume that the two samples are independent simple random samples selected from normally distributed populations. Do...
Assume that the two samples are independent simple random
samples selected from normally distributed populations. Do not
assume that the population standard deviations are equal.
Refer to the accompanying data set. Use a 0.01 significance
level to test the claim that women and men have the same mean
diastolic blood pressure.
(a) calculate the test statistic
t=
(b) find p-vlaue
p-value=
(c) Make a conclusion about the null hypothesis and a final
conclusion that addresses the original claim.
(Reject/no reject)...
Assume that the two samples are independent simple random samples selected from normally distributed populations. Do...
Assume that the two samples are independent simple random
samples selected from normally distributed populations. Do not
assume that the population standard deviations are equal. Refer to
the accompanying data set. Use a 0.01 significance level to test
the claim that women and men have the same mean diastolic blood
pressure.
Women Men
71.0 70.0
94.0 64.0
79.0 67.0
65.0 60.0
73.0 63.0
79.0 71.0
58.0 58.0
51.0 40.0
71.0 67.0
87.0 66.0
67.0 82.0
60.0 74.0
73.0 55.0
61.0 ...
Assume that two samples are independent simple random samples selected from normally distributed populations. Do not...
Assume that two samples are independent simple random samples
selected from normally distributed populations. Do not assume that
the population standard deviations are equal.
A paint manufacturer wished to compare the drying times of two
different types of paint. Independent simple random samples of 11
cans of type A and 14 cans of type B were selected and applied to
similar surfaces. The drying times, in hours, were recorded.
The summary statistics are below.
Type A:
x overbar 1 equals...
Two independent random samples were selected from two normally distributed populations with means and variances (μ1,σ21)...
Two independent random samples were selected from two normally
distributed populations with means and variances (μ1,σ21) and
(μ2,σ22). The sample sizes, means and variances are shown in the
following table.
Sample 1 n1 = 13 x̄1 = 18.2 s21 = 75.3
Sample 2 n2 = 14 x̄2 = 17.1 s2= 61.3
(a). Test H0 : σ12 = σ2against Ha : σ12 ̸= σ2. Use α = 0.05.
Clearly show the 4 steps.
(b). TestH0 :μ1 −μ2 =0againstHa :μ1 −μ2 >0....
The following information was obtained from two independent samples selected from two normally distributed populations with...
The following information was obtained from two independent
samples selected from two normally distributed populations with
unknown but equal standard deviations.
n1=33; x1¯=14.46;
s1=15.07.
n2=23; x2¯=−4.75;
s2=14.65.
Find a point estimate and a 97.5% confidence interval for
μ1−μ2.
For the following, round all answers to no fewer than 4 decimal
places.
The point estimate of μ1−μ2 is:
Answer
The lower limit of the confidence interval is:
Answer
The upper limit of the confidence interval is:
Answer
The margin of error...
ADVERTISEMENT
ADVERTISEMENT
Latest Questions
- A 7800 kg rocket blasts off vertically from the launch pad with a constant upward acceleration...
- For the short essay assignment you will compare Pablo Neruda’s “Ode to a Large Tuna in...
- Case Study As the marketplace for goods and services becomes increasingly global, businesses must understand and...
- Business risk is comprised of (a) price risk, (b) credit risk and (c) pure risk Defined...
- Evaluate Walmart's globalization strategy over the last two decades. Where did the retailer struggle? Where did...
- While technology is a great tool it should not be the absolute answer when it comes...
- Beginning with the Weizsäcker semi-empirical mass formula, show that the minimum in a mass parabola occurs...
ADVERTISEMENT