For a t distribution, If n be the sample size, then
degree of freedom, df = n - 1
Here n = 20, => df = 20-1 = 19
Table VII provides a t-distribution when the population standard deviation (sigma) is unknown. What is the...
When the population standard deviation is unknown | Question 10 1 pts If sampling distributions of sample means are examined for samples of size 1, 5, 10. 16 and 50. you will notice that as n increases in size, the shape of the sampling distribution appears more like that of the: O Even distribution O Population distribution O Uniform distribution D Normal distribution 1 pts DQuestion 11 It has long been reported that human body temperature follows a normal distribution...
QUESTION 5 Which statement concerning the t-distribution is false? O AT follows a standard normal distribution OB. The smaller the degrees of freedom the flatter the curve. OC. The t-distribution has a larger standard deviation than the Standard Normal Curve. OD. T-distributions have a mean of 0. o E. The total area under the density curve depends on the degrees of freedom. QUESTION 6 The t-procedures are robust when A. sample size is 12 and the sample data is not...
A normal distribution is approximated as a Student t distribution when the population standard deviation is unknown. Select one: True on O False
99 and standard deviation σ A population whose distribution is unknown has mean μ and a sample of size 26 is drawn from this population, then 1, a. The mean oJ a b. The standard error ot c. The distribution of A population whose distribution is unknown has mean μ = 99 and standard deviation σ = 7 and a sample of size 26 is drawn from this population, then 1, a. b. c. The mean of X= The standard...
A population has a mean mu= 72 and a standard deviation sigma= 6. Find the mean and standard deviation of a sampling distribution of sample means with sample size n= 36.
A population has a mean u=73 and a standard deviation sigma equals 24. Find the mean and standard deviation of a sampling distribution of sample means with sample size n=64. ux= ox=
10. A normal population with an unknown variance has a mean of 20. Is one likely to obtain a random sample of size 9 from this population with a mean of 24 and a standard deviation of 4.1? If not what conclusion would you draw. Here are some integrals you may find helpful, where h(t) is the probability distribution function for a t-distribution with 8 degrees of freedom h(t)dt = ht) dt = h(t) dt 0.919 0.653 0.983
Question 5 Calculate the two-sided 95% confidence interval for the population standard deviation (sigma) given that a sample of size n=10 yields a sample standard deviation of 12.29. Your answer: O 11.64 < sigma <33.17 8.45 < Sigma <22.44 10.63 < Sigma < 15.74 9.29 < Sigma <23.64 5.28 < sigma <29.78 1.08 < sigma <31.24 11.07 < sigma 16.03 12.20 < Sigma 19.97 14,71 < sigma < 10,43 11.30 < sigma < 13.61
We use the t distribution to construct a confidence interval for the population mean when the underlying population standard deviation is not known. Under the assumption that the population is normally distributed, find tα/2,df for the following scenarios. (You may find it useful to reference the t table. Round your answers to 3 decimal places.) tα/2,df a. A 90% confidence level and a sample of 25 observations. b. A 95% confidence level and a sample of 25 observations. c. A...
QUESTION 5 A sample of 225 elements from a population with a standard deviation of 75 is selected. The sample mean is 180. The 95% confidence interval for? is 105 to 225 175 to 185. 171.78 to 188.22. 170.2 to 189.8. QUESTION 6 "From a population that is normally distributed, a sample of 25 elements is selected and the standard deviation of the sample is computed. For the interval estimation of , the proper distribution to use is the normal...