9. Assume that a simple random sample has been selected from a normally distributedpopulation and test the given claim.0.05In a study of the effects of prenatal cocaine use on infants, the following sample data wereobtained for weights at birth: n = 190, x=2750 g, s = 645 g. Use a 0.01 significance level totest the claim that weights of babies born to cocaine users have a mean that is less that themean of 3103 g for babies born to mothers who do not use cocaine. Based on the results,does it appear that birth weights are affected by cocaine use?

Claim: The mean weights of babies born to cocaine users have a mean that is less than the mean of…

Answered: 9. Assume that a simple random sample…

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

Suppose IQ scores were obtained for 20 randomly selected sets of siblings. The 20 pairs of measurements yield x=101.22, y=102.45, r=0.916, P-value=0.000, and y=−8.44+1.1x, where x represents the IQ score of the older child. Find the best predicted value of y given that the older child has an IQ of 99? Use a significance level of 0.05.
A kilo restaurant implemented a change in the composition and presentation of its dishes. We want to assess whether the average weight of meals served is greater after the changes, compared to the previous average, which was 640. For this purpose, the weights of dishes from a random sample of 10 customers were taken. The average weight of dishes in the sample was 656 and the variance 144. Use a statistical test for the evaluation. Adopt a significance level of 10%. a. What is the value of the test statistic? b. What range of values is the p-value in? c. At the 10% significance level, can you reject the null hypothesis?
Suppose a study reported that the average persin watched 3.37 hours of television per day. a random sample of 15 people gave the number of hours of television watched per day shown below. at the 1% significance level, do the data provide sufficent evidence to conclude that the amount of television watched per day last year by the average person is greater than the value reported in the study? what is the test statistic value for this problem? a.0.28 b.-38 c.none of the above d. 0.58 e.-4.295 f..04 g. 1.94 . the proper conclusion for this problem is? a. reject the null hypothesis we have sufficent evidence to prove the average number of hours people watch tv is more than 3.37 hours. b. Do not reject the null hypothesis we have sufficient evidence to prove the average number of hours of TV watched is greater than 3.37 hours c. Reject the null hypothesis and claim the average number of hours people watch TV is less than 3.37 because the P value is near zero d. Do not reject the null…
A kilo restaurant implemented a change in the composition and presentation of its dishes. We want to assess whether the average weight of meals served is greater after the changes, compared to the previous average, which was 640. For this purpose, the weights of dishes from a random sample of 10 customers were taken. The average weight of dishes in the sample was 656 and the variance 144. Use a statistical test for the evaluation. Adopt a significance level of 10%. a. What is the distribution of the test statistic? b. What kind of alternative hypothesis? c. What is the test's critical value (the value that defines the critical region), on the scale of the test statistic? (If the test is bilateral, enter only one of the values.)
Consider a sample data with x=25 and s=2. Compute a chebyshev’s interval for which at least 89% of the data will lie?
Two brands of batteries are tested, and their voltages are compared. The summary statistics follow. For sample 1, the sample size is 27; the population standard deviation is 0.3 volts and the mean is 9.2 volts. For sample 2, the sample size is 30; the population standard deviation is 0.1 volts and the mean is 8.8 volts. Is the mean of sample 1 smaller than the mean of sample 2? Using a significance level of 0.05. a) Identify the claim and state the hypotheses. b) What is the test statistics? Find the critical values (s). c) Make the decision to reject or not reject the null hypothesis and explain why. d) Graph your decision and include all the values. That is, the mean, the standard deviation, the critical value(s), the rejection region. e) Set up the formula with the correct numbers for the 95% confidence interval of the mean number of jobs.
15) The Carolina Tobacco Company advertises that its best selling cigarette contain at most 40 mg of nicotine, but Consumer Advocate magazine conducts tests of 10 randomly selected cigarettes and find that x−=43.3 mg and s=3.8mg. Other evidence suggests that the distribution of nicotine content is a normal distribution. With a significance level of ∝ =0.01 in testing the company’s claim that the mean nicotine content is at most 40mg.
A researcher would like to evaluate the effectiveness of a pain-relief patch designed for lower back pain. Prior to testing the patch, each of n = 8 patients rates the current level of back pain on a scale from 1 to 10. After wearing the patch for 90 minutes, a second pain rating is recorded. The data are as follows: Include in your responses: A. Compute the mean and variance for the sample of difference scores. B. Provide the Null and alternative hypotheses C. Calculate SSD
. 3. A researcher is interested in knowing if preterm infants with late metabolic acidosis and preterm infants without the condition differ with respect to urine levels of a certain chemical. The mean levels, standard deviations, and sample sizes from the two samples are given below. Assuming that the populations have equal variances: a. Fill in the missing pieces of the Stata output. ttesti 38 8.5 3.5 32 6.85 2.6 X y Two-sample t test with A variances combined diff Obs Ho: diff=0 38 32 Sample With condition 70 diff mean(x) n 38 Without condition 32 Ha: diff |t|) = F [95% Conf. Intervall 7.349579 5.9126 6.98079 .1552544 t = degrees of freedom = 9.650421 7.7874 8.510638 3.144746 E b. What is the conclusion of your test? c. Use this output to construct a 99% confidence interval for the difference between the two means. 68 Ha: diff0 Pr(Tt) = 0.0155
Choose the appropriate statistical test. When computing, be sure to round each answer as indicated. A dentist wonders if depression affects ratings of tooth pain. In the general population, using a scale of 1-10 with higher values indicating more pain, the average pain rating for patients with toothaches is 6.8. A sample of 30 patients that show high levels of depression have an average pain rating of 7.1 (variance 0.8). What should the dentist determine? 1. Calculate the estimated standard error. (round to 3 decimals). [st.error] 2. What is thet-obtained? (round to 3 decimals). 3. What is the t-cv? (exact value) 4. What is your conclusion? Only type "Reject" or Retain"
Suppose IQ scores were obtained for 20 randomly selected sets of couples. The 20 pairs of measurements yield x= 100.1, y = 98.3, r=0.961, P-value = 0.000, and y = - 18.02 + 1.16x, where x represents the IQ score of the wife. Find the best predicted value of y given that the wife has an IQ of 100? Use a significance level of 0.05. Click the icon to view the critical values of the Pearson correlation coefficient r. The best predicted value of y is (Round to two decimal places as needed.)
2. A travel agent claims that the mean price of a round trip flight from San Francisco to Hawaii is less than $510. A simple random sample of 60 round trip flights from San Francisco to Hawaii has a mean price of $502. Assume the population standard deviation is $110. At a significance level of 5%, is there enough statistical evidence to support the travel agent's claim? Requirements: 1. 2. 3. Step 1: State the hypothesis: Họ: Ha: Tail Step 2: Draw your distribution and find critical number(s) Step 3: Compute the test statistics Step 4: Make a Decision: Step 5: Summarize the result: (Restate the level of significance and discuss the claim)

Recommended textbooks for you

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

Elementary Statistics: Picturing the World (7th E…

Statistics

ISBN:

9780134683416

Author:

Ron Larson, Betsy Farber

Publisher:

PEARSON

The Basic Practice of Statistics

Statistics

ISBN:

9781319042578

Author:

David S. Moore, William I. Notz, Michael A. Fligner

Publisher:

W. H. Freeman

Introduction to the Practice of Statistics

Statistics

ISBN:

9781319013387

Author:

David S. Moore, George P. McCabe, Bruce A. Craig

Publisher:

W. H. Freeman

SEE MORE TEXTBOOKS