Nine hundred (900) high school freshmen were randomly selected for a national survey. Among survey participants, the mean grade-point average (GPA) was 2.7, and the standard deviation was 0.4. What is the 95% confidence interval? [Hint: Given the large population, you can assume that the Gaussian distribution and related statistics apply.]

Nine hundred (900) high school freshmen were randomly selected for a national survey. Among survey participants, the mean grade-point average (GPA) was 2.7, and the standard deviation was 0.4. What is the 95% confidence interval? [Hint: Given the large population, you can assume that the Gaussian distribution and related statistics apply.]

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The 95% confidence interval for a one group, continuous outcome scenario is calculated. The mean is 4 with a 95% confidence interval of 2 to 6. These findings are interpreted in the following manner: "We are 95% confident that the true standard deviation is between 2 and 6." Is this a correct interpretation? Yes, it is correct No, it is not correct
The distribution of study times for first year students follows a Normal distribution with standard deviation σσ = 54 minutes. Suppose a sample of 487 students found that the mean study time for these students was x¯x¯= 173 minutes per week. Use this to find a 88.28% confidence interval to estimate the mean study time for all students. We are 88.28% confident that the mean study time for first year students is between minutes_____ and ____ minutes. What is the margin of error for your confidence interval?
Suppose the prices for the iphone 12 are normally distributed with an unknown population mean and a population standard deviation of 75$. A random sample of 50 stores is taken and gives a sample mean price of $850. What are the lower and upper bounds for a 83% confidence interval of the population mean price?
Body Mass Index: In a survey of adults with diabetes, the average body mass index (BMI) in a sample of 1928 women was 31.30 with a standard deviation of 0.3. The BMI in a sample of 1559 men was 30.50, with a standard deviation of 0.6. Part 1 of 2 (a) Construct a 99% confidence interval for the difference in the mean BMI between women and men with diabetes. Let H, denote the mean BMI for women with diabetes. Use the TI-84 calculator and round the answers to two decimal places. A 99% confidence interval for the difference in the mean BMI between women and men with diabetes is Part: 1 / 2 Part 2 of 2 (b) Does the confidence interval contradict the claim that the mean BMI is the same for both men and women with diabetes? The confidence interval (Choose one) this claim.
A market surveyor wishes to know how many energy drinks teenagers drink each week. They want to construct a 80% confidence interval with an error of no more than 0.07 . A consultant has informed them that a previous study found the mean to be 3.6 energy drinks per week and found the variance to be 1.44 . What is the minimum sample size required to create the specified confidence interval? Round your answer up to the next integer.
Next question If a sample proportion is 0.68, which of the following could be a 90% confidence interval for the population proportion? ..... Select all that apply. A. Lower bound: 0.59; Upper bound: 0.77 B. Lower bound: 0.66; Upper bound: 0.70 OC. Lower bound: 0.50; Upper bound: 0.77 D. Lower bound: 0.77; Upper bound: 0.95 E. Lower bound: 0.67; Upper bound: 0.71 F3 F4 F5 F7 F8 24 4. %23 2 3. 6. Left control option command
Please help with statistics question attached.
you conducted additional studies with these men and found the following: a. The RR for those who drank one drink per day was 1.50 (95% CI:1.32-1.67) in comparison to the abstainers. b. For those men who drank three or more drinks per day the RR compared to the abstainers was 4.20 (95% CI 2.68-5.85). Question: We can tell from the Confidence Intervals provided in #7 whether there are likely more people in the “one drink a day” group or the “3+ drinks per day” group. Which one likely has more people and how can we tell?
At a charter high school, the average GPA of a high school senior is known to be normally distributed. After a sample of 27 seniors is taken, the average GPA is found to be 2.85 and the sample variance is determined to be 0.16. Find a 95% confidence interval for the population mean GPA. a. 2.5615 to 2.8585 b. 2.6358 to 3.0642 c. 2.6917 to 3.0083 d. 2.5167 to 2.9033
Question 2: A random sample of 200 observations produced a sample proportion of 0.35. Determine the 98% confidence interval for the population proportion. rt Answer:
Hunter is writing a report on the backgrounds of American presidents. He finds that the mean age of the 45 presidents is 55 years with the standard deviation of 6.59 years. Because Hunter took a statistics course, he calculates a 95% confidence interval for the mean age of all men who have been president to be 55 ± 1.98. Comment on this result. Question 8 options: Hunter can be 95% confident that the mean age of all presidents is 55 years. 95% of all the ages of the presidents lie between 55 ± 1.98. Hunter should have taken a larger sample to reduce the margin of error. Hunter is 95% confident that the mean age of all presidents lies between 53.02 and 56.98 years. The confidence interval makes no sense since Hunter has the entire population of ages.
A 95% confidence interval implies that: A. We are 95% confident that the interval contains the true population mean B. The interval range contains 95% of the values in your dataset C. There is a 5% chance the mean will be found in the CI range