using the t distribution to conduct a test is better than using a z test as the z test requires the researcher to know the population variances. true or false
using the t distribution to conduct a test is better than using a z test as...
Circle the right answer and if it is false, correct it. (a) Z test requires that you know the standard deviation of the sample. TRUE or FALSE (b) If we are using a t-test and we reject the null hypothesis, we can be sure that the population means are different. TRUE or FALSE (c) α is the level of Type II error that we can expect. (5pts) TRUE or FALSE (d) A F-distribution is skewed to the right. TRUE or...
Which of the following is a key difference between the t test and the z-test? a. The t test requires the knowledge of the true population mean. b. The t test uses the sample variance in place of the population variance. c. The t test computes the standard error using the population standard deviation. d. All of these are differences between t and z.
1. In order to test the treatment A is better than B, we conduct an experiment and obtain the following table Success Failure Trt A 4 Trt B 2 6 (a) Compute p-value of the Fisher's exact test (b) Compute p-value of approximated test based on CLT (i.e., z-test (c) Which one do you think appropriate? Justify your answer (*) Do NOT use chisq.test() function in R.
Suppose we want to conduct a hypothesis test relating to the mean of a certain population where the population variance is unknown. To conduct the test, we collect data from a random sample of 27 members of the population. a. Explain why we should use a t-test instead of a z-test in this situation. What is the distribution of the t-statistic in this case? (Recall that the t-statistic is defined as ? = ?̅−? ?/√? ) b. Find the following...
You can use both the t-statistic and the Z-statistic to test hypotheses about the mean of a population. The test that uses the t-statistic is typically referred to as a t test, while the test that uses the z-statistic is commonly called a z test. IO Which of the following statements are true of the t-statistic and the t distribution? Check all that apply. The formula for the t-statistic is t = (x - 1) / s/vn. When the population...
11 a) True or False: The t distribution has a greater standard deviation than the standard normal z distribution. Can you explain or prove why this is True? I have a hunch it has something to do with the sample sizes vs the population but I'm really not sure & I really like to be able to explain why things are true or false for questions like this. Thanks!
If you are using SPSS to conduct a two independent samples t-test, examining the impact of your independent variable of "smoking status" (smoker vs. non-smoker) on your dependent variable of "number of cavities reported in a 3 year period", the variable of "smoking status" would be your identified "Grouping Variable" in the Independent Samples T-Test pop up box. Is this true or false?
Question 8 2 pts When calculating a t-test statistic in a hypothesis test, it is based on information obtained only from the population. True False Question 9 2 pts A continuous normal distribution has the same probability at each individual value of X. True False Question 10 2 pts Confidence intervals and hypothesis testing are examples of how a researcher performs inferential statistics. True False
Which of the following statements is true? The t-distribution with 1 degree of freedom is equivalent to the standard normal distribution. When division by a factor of n-1 is used, the sample variance s2 is an unbiased estimator of the population variance σ2. 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. A 99% z-based confidence interval of the population mean μ based on a sample...
The hypothesis test for the proportions is calculated using a z test statistic since proportions are based on a binomial distribution. True or False