Student t distribution is used when the sample size is less than 30. True or false
Student t distribution is used when the sample size is less than 30. True or false
For the following, circle true or false and if false, explain why. A) The sampling distribution of sample means is normally distributed when the population has any distribution and the sample size is less than or equal to 30. TRUE or FALSE B) The sampling distribution of sample means is normally distributed when the population is normally distributed and the sample is any size. TRUE or FALSE
with increasing sample size, the t distribution tends to become flatter in shape. true or false
True or False? If the sample size is equal to 40 and the true proportion is equal to 0.25, then the z-distribution can be used instead of the binomial distribution for calculating probabilities. True or False? When sampling from a normal distribution where the mean= u and variance= o^2, then the sampling distribution for x will also have a mean= u and a variance= o^2
If a sample size is greater than 30, which of the following characteristics of the distribution of sample means is true? a.) Nothing can be assumed about the distribution of sample means. b.) The sample size needs to be increased by 10% so we can apply the Central Limit Theorem. c.) The distribution of sample means has a binomial distribution. d.) The distribution of sample means is approximately normal.
1. Select all true statements about sample mean and sample median. A) When the population distribution is skewed, sample mean is biased but sample median is an unbiased estimator of population mean. B) When the population distribution is symmetric, both mean and sample median are unbiased estimators of population mean. C) Sampling distribution of sample mean has a smaller standard error than sample median when population distribution is normal. D) Both mean and median are unbiased estimators of population mean...
For hypothesis test about a mean, you should use a sample size greater than 30 when A. the population distribution is not normal B. the p-value is less than α C. the population size is large D. the significance level is greater than 1
QUESTION 1 The higher the sample size the less the confidence level. True False QUESTION 2 The confidence interval does not depend of the standard deviation. True False
Answer the following True or False: Suppose a sample size of 87 was used to conduct a right tailed hypothesis test for a single population mean. The null hypothesis was H0: μμ = 45 and the sample mean was 50 and the p-value was 0.03. Then there is a 3% chance that 87 randomly selected individuals from a population with a mean of 45 and the same standard deviation would have a sample mean greater than 50. false true
If sample distribution is skewed to the right, what must be true about the sample size? Sample size must be small Sample size must be more than 30. It does not matter what the sample size is. Not enough information.
A normal distribution is approximated as a Student t distribution when the population standard deviation is unknown. Select one: True on O False