What is the null distribution of the test statistic? How do we know if it is normal or not, and how do we calculate it?

Q: The data table contains waiting times of customers at a bank, where customers enter a single waiting…

A: State the hypotheses

Q: A researcher wants to determine if body weight is associated with the number foreign countries a…

A: ANOVA is used to test whether the mean of three or more groups are equal.Pearson's correlation is…

Q: Assume that adults were randomly selected for a poll. They were asked if they "favor or oppose using…

A: Solution:  Given information :  n = 490 favor + 395 opposed = 885 sample size  X = 490 favor…

Q: What is the standard deviation of these sample data?Y -2 1 3 2 -1 0 4 6

A:

Q: The final scores of games of a certain sport were compared against the final point spreads…

A: From the provided information, Sample size (n) = 225 Sample mean (x̅) = -1.1 Population standard…

Q: What information is provided by calculations of the “t” test statistic?

A:

Q: standardized scores and normal

A: Normal distributions have a specific curve, and I’ve already posted about that elsewhere; the…

Q: What is the benefit of modeling a random variable with a normal distribution

A: Here we have to give the reason for the benefit of modeling a random variable with a normal…

Q: Calculate the sample standard deviation of the data shown. Round to two 17 22 25 15 19 13 24 sample…

A:

Q: Stem-and-Leaf Display: Amount of Magnesium Leaf Unit = 0.1 N = a = 45 3 1 345 11 (13) b = 21 4…

A: write the data set........then find the maximum frequency......

Q: (c) Find the standardized test statistic z. Z= (Round to two decimal places as needed.) an example…

A: Given that  Sample size n =300 Sample proportion p^=72%=0.72

Q: Consider you recently took an exam in your history class and your exam has been returned to you. The…

A: Given: Consider you recently took an exam in your history class and your exam has been returned to…

Q: When is the population standard greater than the population variance?

A: Variance: The variation between each observation from its mean is known as variance. The greater the…

Q: Explain when a random variable might be modelled using a Normal distribution, and give an example of…

A: Mathematically, Whenever a random variable is formed by adding a number of other individual…

Q: data for two independent normal samples can be found in the table. We want to check if the…

A: The objective of this question is to determine if the population variances of two independent normal…

Q: Find the test statistic for the problem?

A: It is given that Sample size n = 450 Number of patients had a successful knee surgery operation, X =…

Q: When do we use a t-statistic instead of a z-statistic to help infer a mean?

A: Hypothesis tests are used to test population claims. It has two population statements, where one is…

Q: The Summary statistics for two samples of data are Sample 1: mean = 19 variance = 10 Sample 2: mean…

A: 1. Spread of the observations is based on the the variance. The sample 1 variance is 10. The sample…

Q: A certain drug is used to treat astihma. In a clinical trial of the drug, 17 of 266 trealed subjects…

A: Given.sample size n=266          and x=17Sample proportion p^=xnp^=17266=0.0639d)  Null…

Q: what test is used to determine whether two population means are different when the variance are…

A: The test that is used to determine if the two population means are different when the population…

Q: What is formula for the variance of the population?

A:

Q: what test is used to determine whether two population means are different when the variance are…

A: Solution :  when the variance are known and sample size is large then we use z test to determine…

Q: what is the difference between the distribution of a sample, distribution of the population, and the…

A: A sample is the subset of the population taken randomly to define the characteristics of the…

Q: What does it mean that the variance (computed by dividing by N) is a biased statistic?

A:

Q: aw a random sample from a normal distribution. Is the sample standard deviation an ate of the…

A: We have given that, We draw a random sample froma normal distribution. Is the sample standard…

Q: vrinkles after just 14 days of application. To test the claim, 10 women are randomly selected to…

A: The paired sample t-test , sometimes called the dependent sample t-test , is a statistical procedure…

Q: The following data show the probabilities for the number of cars sold in a given day at Alex's car…

A:

Q: What is the explanation for the normality test?

A: Here we explain normality test.