1. What factor determines whether you should use a z-test or a t-test statistic
ID: 2948122 • Letter: 1
Question
1. What factor determines whether you should use a z-test or a t-test statistic for a hypothesis test? 11.2 A sarmple of n 16 individuals is selected from a population mean of ? 74, A treatment is administered to the individuals in the sample and, after treatment, the sample variance is found to be s -64 a. If the treatment has a 3-point effect and produces a sample mean of M- 77, is this sufficient to conclude that there is a significant treatment effect using a two-tailed test with a-05? b. If the treatment has a 6-point effect and produces a sample mean of M- 80, is this sufficient to conclude that there is a significant treatment effect using a two-tailed test with a 05? 1.3 A major corporation in the Northeast noted that last year its employees averaged H-5.8 absences during the winter season (December to February). In an attempt to reduce absences, the company offered free flu shots to all employees this year For a sample of n 100 people who took the shots, the average number of absences this winter was M = 3.6 with SS·. 396 Do these data indicate a significant decrease in the number of absences? Use a one-tailed test with a- 05 11.4 On a standardized spatial skills task, normative data reveal that people typically get ?-15 correct solutions. A psychologist tests n-7 individuals who have brain injuries in the right cerebral hemisphere. For the following data, determine whether or not right-hemisphere damage results in significantly reduced performance on the spatial skills task. Test with alpha (?) set at .05 with one tail The data are as follows: 12, 16, 9, 8, 10, 17, 10.Explanation / Answer
As there is 4 questions with different subparts so I can do only the first question
11.1
suppose hypothesis is
H0 : m0 = m1 vs. H1 : m0 != m1
then there may be two possiblity
1. population variance is known
2. population variance is unknown
For case 1 in testing of hypothesis we use Z -statistic
For case 2 in testing of hypothesis we use t - statistic . In this case we need to estimate population variance by sample variance.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.