Paird t test. Option B is correct.
The sample of 400 would give a margin of error smaller than 5. Option A is correct.
Two sample t tesg for difference in means. Option C is correct
A random sample of university students were asked whether they participate in varsity athletics and how...
2. Suppose that a random sample of 41 state college students is asked to measure the length of their right foot in centimeters. A 90% confidence interval for the mean foot length for students at this university turns out to be (21.709, 25.091). If we now calculated a 95% confidence interval, would the new confidence interval be wider than or narrower than or the same as the original? b. Suppose two researchers want to estimate the proportion of American college...
A random sample of students were asked whether they were satisfied with their school's lunch menu. The resulting confidence interval for the proportion of students who are satisfied is (0.33,0.51). What is the margin of error?
8. A random sample of 25 college males was obtained and each was asked to report their actual height and what they wished as their ideal height. A 95% confidence interval for μd= average difference between their ideal and actual heights was 0.8" to 2.2". Based on this interval, which one of the null hypotheses below (versus a two-sided alternative)can be rejected? A. H0: μd= 0.5 B. H0: μd= 1.0 C. H0: μd= 1.5 D. H0: μd= 2.0 9. The...
In the survey of a random sample of students at a university, two questions were, “How many hours per week do you usually study?” and “Have you smoked marijuana in the past six months?” An analysis of the results produced the following SPSS output: A research question of interest is whether students who have smoked marijuana (group Y) in the past 6 months differ in study hours on average per week than those who have not (group N). Using...
Dependent Sample T-Test Researchers were interested in studying whether the type of food eaten influences appearance perception. Participants were shown 2 pictures of a woman eating either fast food (i.e., a burger with fries) or healthier food (i.e., a salad). The participants were then asked to rate the woman’s level of attractiveness on a scale of 1 (very unattractive) to 7 (very attractive). Given the above information, answer the questions below (assume a level of significance of .05). State the...
In a random sample of 275 students at a university, 225 stated that they were nonsmokers. Based on this sample, compute a 92 % confidence interval for the population proportion of all students at the university who are smokers. What is the Best point estimate, Margin of Error and Include the written statement.
13. In which of the following cases would an independent two sample t test be inappropriate? a. Comparing weight loss in excitable and calm people on a similar diet. b. Comparing IQ of men and women. -c. Comparing changes of attitudes of students from their Freshmen to their Senior year. d. Comparing vitamin C retained in broccoli when cooked by steaming or boiling. 14. Null and alternative hypotheses are statements about - a population parameters c. sample statistics b. sample...
Independent random samples were selected from two quantitative populations, with sample sizes, means, and standard deviations given below. n = n2 = 90, x1 = 125.3, %2 = 123.8, s, = 5.7, s, = 6.9 Construct a 95% confidence interval for the difference in the population means ( M M ) (Round your answers to two decimal places.) Find a point estimate for the difference in the population means, Calculate the margin of error. (Round your answer to two decimal...
A random sample of community college students was asked the number of hours they sleep on a typical week-night during a given academic term. The sample data are as follows: 8 6 4 5 3 7 S 4 3 4 4 5 6 8 7 7 7 3 3 4 What is the 90% confidence interval estimate for the true mean amount of sleep time per night spent by community college students during a academic term? a) The data give...
1. A random sample of size n is drawn from a population that is normally distributed with a standard deviation of 8. The sample mean is found to be 50. 1.a) Construct a 98% confidence interval (CI) for the population mean uif the sample size is 16. The critical value used is The (margin of) error for the 98% confidence interval (C.I.) is The resulting Cl is 1.b) Construct a 95% confidence interval for the population mean u if the...