Which of the following statements is true?
The t-distribution with 1 degree of freedom is equivalent to the standard normal distribution. |
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When division by a factor of n-1 is used, the sample variance s2 is an unbiased estimator of the population variance σ2. |
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If a hypothesis test is conducted at the 5% significance level, then a p-value of 0.087 would lead the researcher to reject H0. |
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A 99% z-based confidence interval of the population mean μ based on a sample will be narrower than a 95% z-based confidence interval of the population mean μ based on the same sample. |
Following statement is correct
A 99% z-based confidence interval of the population mean μ based on a sample will be narrower than a 95% z-based confidence interval of the population mean μ based on the same sample.
Confidence interval formula is given as follows
Width of confidence interval will be larger if Z score will be larger. Z score is directly proportional to confidence level. Hence last statement is correct.
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Which of the following statements is true? The t-distribution with 1 degree of freedom is equivalent...
1. (40) Suppose that X1, X2, Xn forms an independent and identically distributed sample from a normal distribution with mean μ and variance σ2, both unknown: 2nơ2 (a) Derive the sample variance, S2, for this random sample. (b) Derive the maximum likelihood estimator (MLE) of μ and σ2 denoted μ and σ2, respectively. (c) Find the MLE of μ3 (d) Derive the method of moment estimator of μ and σ2, denoted μΜΟΜΕ and σ2MOME, respectively (e) Show that μ and...
6. Consider the following sample: Xi = -2, X2 = 12. X7-1.5, Xs -0.5, a. Estimate the population mean, μ, using an analogical estimator. b. Estimate the population variance. ơ2, using a biased and an unbiased estimator. c. Assuming that the random sample is drawn from a normal population with known variance, σ2-4, construct a 95% confidence interval for the population mean. d. Assuming that the random sample is drawn from a normal population with unknown variance, σ2, construct a...
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Suppose that Y1 , Y2 ,..., Yn denote a random sample of size n from a normal population with mean μ and variance 2 . Problem # 2: Suppose that Y , Y,,...,Y, denote a random sample of size n from a normal population with mean u and variance o . Then it can be shown that (n-1)S2 p_has a chi-square distribution with (n-1) degrees of freedom. o2 a. Show that S2 is an unbiased estimator of o. b....
If a null hypothesis is rejected at a significance level of 1%, then we should say that it was rejected at 1%. Reporting that the null was also rejected at the 5% level of significance is unnecessary and unwise. True False The p-value equals alpha, the level of significance of the hypothesis test. True False THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: Let X1, X2, X3, and X4 be a random sample of observations from a population with...
12. As the number of degrees ot trdom ort d n s the the t distribution andd the standard nomal dist becomes larger b becomes smalter stays the same huctuates. d. 13. In interval esionation, thet distribution is applicatle ondy when a. the population has a mean of tess than 30 b. the sample standard deviation is used to estimate the population standard deviation the variance of the population is known d. the mean of the population is unknown. C....