We need data of the 8 samples before and after treatment. Otherwise r square cannot be computed..
So providing the answer for the part sample variance 72
Capter question 17 Aa Aa A random sample of n 8 scores is obtained from a...
A random sample of n - 16 scores is selecdted from a normal population with a mean of p - 50. After atreatment is administered to the individuals in the sample, the sample mean is found to be M -54 If the population standard deviation is σ-8, is the sample mean sufficient to conclude that the treatment has a significant effect? Use a two-tailed test with α-.05. (Hint: Recall that the critical value for a two-tailed test with α-.05 is...
Aa Aa Tips 4. Factors that influence a hypothesis test Suppose you conduct a hypothesis test about a population mean when the standard deviation is unknown by calculating at statistic and determining whether to reject the null hypothesis. Assume that your statistic is a positive value and that you will reject the null hypothesis when t is very large. For each of the potential changes to the components of your study design or the results listed below, determine the change...
To test the effectiveness of a treatment, a sample of n = 36 people is selected from a normal population with mean of μ = 60. After the treatment is administered to the individuals in the sample, the sample mean is found to be M = 55. (a) If the population standard deviation is σ = 13, can you conclude that the treatment has a significant effect? Use a two-tailed test with α = 0.05. (Round your answers to two...
Focusing on the last part 41. Gravetter/Wallnau/Forzano, Essentials-Chapter 8-End-of-chaptor question 15 Aa Aa A high school teacher has designed a new course intended to help students prepare for the mathematics section of the SAT. A sample of n -20 students is rearuited to take the course and, at the end of the year, each student takes the SAT. The average score for this sample is M 562. For the general population, scores on the SAT are standardized to form a...
A sample of n = 6 individuals is selected from a population with µ = 25. After a treatment is administered to the individuals, the sample mean is found to be M = 27. A. If the sample variance is s = 4, then conduct a hypothesis test to evaluate the significance of the treatment effect and calculate r2 to measure the size of the treatment effect. Use a two-tailed test with α = .05. B. If the sample variance...
A random sample of n = 12 individuals is selected from a population with µ = 70, and a treatment is administered to each individual in the sample. After treatment, the sample mean is found to be M = 74.5 with SS = 297. Use the Distributions tool to help answer the questions that follow. t Distribution Degrees of Freedom = 21 -3.0-2.0-1.00.01.02.03.0x.5000.50000.000 QUESTION: How much difference is there between the mean for the treated sample and the mean for...
To evaluate the effect of a treatment, a sample of n = 6 is obtained from a population with a mean of μ 80, and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M- 72. Select a Distribution Distributions 02 If the sample variance is s2 54, are the data sufficient to conclude that the treatment has a significant effect using a two-tailed test with α-.05? Complete the following...
To evaluate the effect of a treatment, a sample of n-8 is obtained from a population with a mean of ?-50, and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M 55. a) If the sample variance is s-32, use a two-tailed test with ?-0.05 to determine whether the treatment effect is significant and compute Cohen's d b) If the sample variance is s- 72, repeat the test and...
11. Effect size and Cohen's d Aa Aa Suppose a researcher is trying to understand whether people who purchase fast-food hamburgers would be willing to pay more if the hamburger comes with a free cookie. Prior research suggests the mean amount customers say they are willing to pay for a hamburger is -4.14 and ơ-1.40 The researcher plans to conduct a study very similar to the prior research by selecting a sample of customers and asking them how much they...
A random sample is obtained from a population with a mean of μ = 100, and a treatment is administered to the sample. After treatment, the sample mean is found to be M = 104 and the sample variance is s2 = 400. (a) Assuming the sample contained n = 16 individuals, measure the size of the treatment effect by computing the estimated d and r2. (Use 3 decimal places.) d = r2 = (b) Assuming the sample contained n...