Economics- Probability and stats
Economics- Probability and stats 1. Find the value of the 75th percentile of the following array:...
Probability 5. The discrete random variable Z has the following probability distribution 2 0.2 4 P(Z) 0.1 0.25 0.05 0.3 Which of the following is FALSE? A) P(Z < 2) 0.55 B) P(Z 2 4)- 0.45 C) P(Z 4)=0.9 D) P(Z3)-0.05 6. A random sample of 100 first-year students was selected to determine the average GPA they achieved at a university. A 95% confidence interval for the average GPA of the first-year students was 5.2 < H < 6.8 based...
1. Suppose that you are testing the following hypotheses: ?0: ? = 10 and ?1: ? > 10. If the null hypothesis is rejected at the 1% level of significance, what statement can you make about the confidence interval on the mean? a.) The lower bound of a 95% one-sided confidence interval on the mean exceeds 10 b.) 9 ≤ ? ≤ 13 c.) No statement can be made d.) The lower bound of a 95% one-sided confidence interval on...
Suppose that you are testing the following hypotheses: Ho: = 10 and 11: > 10. If the null hypothesis is rejected at the 1% level of significance, what statement can you make about the confidence interval on the mean? a) The lower bound of a 95% one-sided confidence interval on the mean exceeds 10. b) 9 sus 13 c) No statement can be made. d) The lower bound of a 95% one-sided confidence interval on the mean exceeds zero. If...
Bonus (5 points) Suppose that you are testing the following hypotheses: Ho: 4 = 10 and H :> 10. If the null hypothesis is rejected at the 1% level of significance, what statement can you make about the confidence interval on the mean? a) The lower bound of a 95% one-sided confidence interval on the mean exceeds 10. b) 9 <u< 13 c) No statement can be made. d) The lower bound of a 95% one-sided confidence interval on the...
Probability FOR THE NEXT FOUR QUESTIONS (QUESTIONS 8-11) USE THE FOLLOWING INFORMATION The CEO of a cosmetic company claims that 75% of her current customers are satisfied with the products they buy. To test her claim, a research group surveyed 350 customers, using simple random sampling. The results revealed that 280 customers said that they are very satisfied with the products. 8. The null hypothesis test is ) μ=0.75 B) p=0.75. C) p 0.75 D)p>0.75 9. The variance of the...
In order to compare the means of two populations, independent random samples of 400 observations are selected from each population, with the results found in the table to the right. Complete parts a through e below. Sample 1 overbar x = 5,305 s1= 154 Sample 2 overbar x = 5,266 s2 = 199 a. Use a 95% confidence interval to estimate the difference between the population means (mu 1 - mu 2). Interpret the confidence interval. The confidence interval is...
For a one-tailed hypothesis test (upper tail) the p-value is computed to be 0.034. If the test is being conducted at 95% confidence, the null hypothesis Select one: a. is rejected. b. is not rejected. c. could be rejected or not rejected depending on the value of the mean of the sample. d. could be rejected or not rejected depending on the sample size.
From a sample of 37 stolen watches, you find that the mean cash value is $950. The standard deviation for your sample is $90. Test the null hypothesis that your sample came from a population whose mean cash value (Mu) is $1,000 against the alternative hypothesis that Mu is different than $1,000. Use alpha = .05. a. Formally state the alternative and the null hypothesis for this test b. What is the critical value(s) for this test? c. Compute and...
1 . A sample of 20 cans of tomato juice showed a standard deviation of 0.4 ounces. A 95% confidence interval estimate of the variance for the population is . 0.2313 to 0.8533 b. 0.2224 to 0.7924 c. 0.3042 to 0.5843 d. 0.0925 to 0.3413 2. Last year, the standard deviation of the ages of the students at UA was 1.8 years. Recently, a sample of 31 students had a standard deviation of 2.1 years. We are interested in testing...
For each problem, select the correct response. (a) What is the P-value of a test of the null hypothesis? A. The probability the null hypothesis is false B. The probability, assuming the null hypothesis is false, that the test statistic will take a value at least as extreme as that actually observed C. The probability the null hypothesis is true D. The probability, assuming the null hypothesis is true, that the test statistic will take a value at least as...