Answered: t-Test for Equality of Means t df Sig.…

t-Test for Equality of Means t df Sig. (Two- Mean Std. Error Tailed) Difference Difference Equal variances assumed -1.847 18 .081 -10.00 5.41 Equal variances not -1.847 assumed 17.9 .081 -10.00 5.41

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

A new screening test for Lyme disease is developed for use in the general population. The sensitivity and specificity of the new test are 60% and 70%, respectively. Five hundred people are screened at a clinic during the first year the new test is implemented. Assume the true prevalence of Lyme disease among clinic attendees is 10%. Calculate the predictive value of a positive test.
True or False? A randomized controlled trial evaluates the efficacy of hydroxychloroquine, as compared to placebo, as a prophylactic treatment to prevent COVID-19 infection in high-risk healthcare workers. The study provides data on a number of demographic characteristics and medical conditions at baseline. The mean age of participants randomized to receive hydroxychloroquine was 31 years and the mean age of participants randomized to receive placebo was 34 years, with p = 0.13. We can conclude that there is no statistically significant difference in mean ages of participants randomized to receive hydroxychloroquine as compared to placebo.
Data from the Department of Motor Vehicles indicate that 80% of all licensed drivers are older than age 25. In a sample of n = 50 people who recently received speeding tickets, 33 were older than age 25 and the other 17 were age 25 or younger. Is the age distribution for this sample significantly different from the distribution for the population of licensed drivers? Use alpha = .05. In a sample of n = 50 people who recently received parking tickets, 36 were older than age 25 and the other 14 were age 25 or younger. Is the age distribution for this sample significantly different from the distribution for the population of licensed drivers? Use alpha = .05.
A 2012 survey of 417 American adults indicates that 15% of cell phone owners do their browsing on their phone rather than a computer or other device. According to an online article, a report from a mobile research company indicates that 38% of Chinese mobile web users only access the internet through their cell phones. We wish to conduct a hypothesis test to determine if these data provide strong evidence that the proportion of Americans who only use their cell phones to access the internet is less than the Chinese proportion of 38%. (a) The Null Hypothesis, in mathematical symbols, is: H0: p = ______ (b) The Alternative Hypothesis, in mathematical symbols, is: HA : p = _______ In both the null and alternative hypotheses, the symbol ( p ) is the proportion of American adult cell phone owners who do their browsing on their phone. (c) The standard error based on the null hypothesis is... :________ (d) Our data indicates a proportion of Americans who use their phones to browse is…
Productivity is the key driver of wages and one of the most importantdeterminants of living standards. The British Chambers of Commercecommissioned research into understanding whether labour productivity in theautomotive manufacturing sector in England and Ireland were the same ordifferent. The researchers collected data on a random sample of 8 firms inEngland and 4 in Ireland and recorded productivity in units of value added (£)per hour. It is assumed that firm-level productivity has a normal distribution.The following data were collected:Ireland 47 56 43 68England 39 50 39 45 50 43 35 43(i) Set up appropriate null and alternative hypotheses and conduct a test ofthe hypotheses of equal mean productivity in Ireland and England at 5 percent significance level under the assumption of unknown but equalpopulation variances. Provide as much detail as possible on yourprocedures. Clearly show all your steps in testing and state your decision.Discuss the economic implications of your findings.…
Hutchinson-Gilford progeria syndrome is a rare genetic condition that produces rapid aging in children. In individuals with this syndrome, cardiovascular disease is a common cause of death in the teenage years. A clinical study examined the effect of treatment with the drug lonafarnib on a number of physiological outcomes. The researchers measured the pulse wave velocity (PWV) of 18 children diagnosed with progeria and recruited worldwide. The study reports that the mean PWV of 18 children diagnosed with progeria is 12.44 m/s, and the standard deviation is 3.638 m/s. Assuming that PWV is normally distributed, is there significant evidence that the mean PWV of children with progeria is abnormally high (i.e. greater than 6.6 m/s)? Let � (pronounced as "mu") be the true mean PWV of children with progeria. What are the two competing hypotheses? ["", "", "", ""] What is the test statistic? ["", "", "", ""] What is the p value? ["", "", "", ""] What is the rejection…
A study in a journal published by the American Academy of Pediatrics (as reported in the Miami Herald, Jan. 14, 1997) seems to suggest that preschoolers who drink more than 12 ounces of fruit juice a day tend to be heavier and shorter than preschoolers who do not. The study involved a random sample of 168 healthy youngsters of whom 59 drank on average more than 12 ounces of fruit juice per day. Each child was weighed and measured. The measurements were then converted to percentage of normal height and weight for a child of that age and gender. For example, a weight percentage of 1.1 indicates that the child is 10% heavier than average. A recorded 0.80 indicates the child is 20% below the average. An average weight is recorded as 1.0. Same with height. Column 1: Juice 1- indicates child DID drink > 12 oz 2- child DID NOT drink > 12 oz Column 2: Weight% weight converted to percent of…
Trans-Generational Effects of Diet Can experiences of parents affect future children? New studies16 suggest that they can: Early life experiences of parents appear to cause permanent changes in sperm and eggs. In one study, some male rats were fed a high-fat diet with 43% of calories from fat (a typical American diet), while others were fed a normal healthy rat diet. Not surprisingly, the rats fed the high-fat diet were far more likely than the normal-diet rats to develop metabolic syndrome (characterized by such things as excess weight, excess fat, insulin resistance, and glucose intolerance.) What surprised the scientists was that the daughters of these rats were also far more likely to develop metabolic syndrome than the daughters of rats fed healthy diets. None of the daughters and none of the mothers ate a high-fat diet and the fathers did not have any contact with the daughters. The high-fat diet of the fathers appeared to cause negative effects for their daughters. What are the…
A study was made of 413 children who were hospitalized as a result of motor vehicle crashes. Among 290 children who were not using seat belts, 60 were injured severely. Among 123 children using seat belts, 16 were injured severely (based on data from "Morbidity Among Pediatric Motor Vehicle Crash Victims: The Effectiveness of Seat Belts," by Osberg and Di Scala, American Journal of Public Health, Vol. 82, No. 3). For this problem we want to know, is there sufficient sample evidence to conclude, at the 0.05 significance level, that the proportion of severe injuries is higher for children not wearing seat belts? Let pi be the proportion of severe injuries among all children not wearing seatbelts and who were involved in crashes. Let p2 be the proportion of severe injuries among all children wearing seatbelts and who were involved in crashes. Which is the proper expression of Ho? Pi = P2 O Pi P2 Which is the proper expression of H1? O pi P2 Calculate p1 to 4 decimal places: Calculate p,…