An experiment was undertaken to determine whether filtering a detergent to remove insolubles would make any difference in the results of the spectrophotometric determination of phosphorus. Each sample was divided into two parts: one half was filtered, the other half was not, and the rest of the analysis was identical for both halves of the sample. The results from the six different detergents are: Sample Filtered, mg/L Unfiltered, mg/L A B D E F 37.1 26.4 26.2 33.2 24.3 34.7 35.2 26.0 25.7 32.8 24.7 33.1 Does filtering make any appreciable difference to the results?

An experiment was undertaken to determine whether filtering a detergent to remove insolubles would make any difference in the results of the spectrophotometric determination of phosphorus. Each sample was divided into two parts: one half was filtered, the other half was not, and the rest of the analysis was identical for both halves of the sample. The results from the six different detergents are: Sample Filtered, mg/L Unfiltered, mg/L A B D E F 37.1 26.4 26.2 33.2 24.3 34.7 35.2 26.0 25.7 32.8 24.7 33.1 Does filtering make any appreciable difference to the results?

Name: Please use alpha= 0.05. thak u An experiment was undertaken to determi
Uploaded: 2024-03-20T07:07:37.000Z
Channel: Bartleby
Description: Please use alpha= 0.05. thak u An experiment was undertaken to determine whether filtering a detergent to remove insolubles would make anydifference in the results of the spectrophotometric determination of phosphorus. Each sample was divided intotwo

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 sample of men and women who had passed their driver's test either the first time or the second time were surveyed, with the following results: Results of the driving testGender First time Second timeMen 126 211Women 135 178a) Do these data suggest that there is a relationship between gender and the passing of their driver’s test from which the present sample was drawn? Let alpha=.05
Suppose a researcher is interested inthe effectiveness in a new childhood exercise program implemented in a SRS of schools across a particular county. In order to test the hypothesis that the new program decreases BMI (Kg/m2), the researcher takes a SRS of children from schools where the program is employed and a SRS from schools that do not employ the program and compares the results. Assume the following table represents the SRSs of students and their BMIs. Student intervention group BMI (kg/m2) Student control group BMI (kg/m2) A 18.6 A 21.6 B 18.2 B 18.9 C 19.5 C 19.4 D 18.9 D 22.6 E 24.1 F 23.6 A) Assuming that all the necessary conditions are met (normality, independence, etc.) carry out the appropriate statistical test to determine if the new exercise program is effective. Use an alpha level of 0.05. Do not assume equal variances.B) Construct a 95% confidence interval about your estimate for the average difference in BMI between the groups.
A psychologist at a private mental hospital was asked to determine whether there was a clear difference in the length of stay for patients with different categories of diagnosis. Looking at the last four patients in each of the three major categories, the results (in terms of weeks of stay) were as follows: Diagnosis Category Affective Disorders Cognitive Disorders Drug-Related Conditions 7 12 8 6 8 10 5 9 12 6 11 10 Using alpha = 0.05, is there a significant difference in length of stay among diagnosis categories? Show all five steps of hypothesis testing. For additional practice, compute the means and standard deviations for each group. What is the purpose of a post hoc test? What does it tell us? Explain why we do not need a post hoc test if there are only two groups in our study. Conduct Tukey's HSD post hoc test to determine where there is a difference in the three groups.
A psychologist at a private mental hospital was asked to determine whether there was a clear difference in the length of stay for patients with different categories of diagnosis. Looking at the last four patients in each of the three major categories, the results (in terms of weeks of stay) were as follows: Diagnosis Category Affective Disorders Cognitive Disorders Drug-Related Conditions 7 12 8 6 8 10 5 9 12 6 11 10 Using alpha = 0.05, is there a significant difference in length of stay among diagnosis categories? Show all five steps of hypothesis testing and compute the means and standard deviations for each group.
A study was performed on 200 elementary school students to investigate whether regular Vitamin A supplementation was effective in preventing colds during the month of March. 100 were randomized to receive daily Vitamin A supplements during the month of March, and 100 students were randomized to a placebo group (and did not receive Vitamin A) during the same month. The number of students getting at least one cold in March was computed in the two groups, and the results are given in the following 2 X 2 table. Using a 5% level of significance determine whether there is an association between Vitamin A supplementation and prevention of Common Cold ColdNo Cold Vitamin A1585100 Placebo2575100 40160200
31% of all pygmy softshell tortoises have stripes on their shells. A herpetologist in Cititon collects a sample of 28 pygmy softshell tortoises and finds that 8 of them have stripes on their shells. Is there enough evidence to conclude, at a significance of alpha = 0.05, that the proportion of pygmy softshell tortoises in Cititon with stripes on their shells is less than 31%? What is the claim? What is the null hypothesis? What is the alternative hypothesis? What is the test statistic? What is/are the critical value(s)? Do we reject the null hypothesis? What conclusion do we draw? What is the P-value for the problem above?
A test of body reaction to the Malaysian citizens who have taken their vaccine was conducted. Selected citizens who got side effect are categorised according to their blood type and the type of vaccine received. From a sample of 250 citizens, 150 of them were administered with Sinovac while the rest received AstraZeneca. Table 4 shows the number of citizens who had side effect after being vaccinated. Type of vaccine Blood type A B AB O Sinovac 50 M 50 20 AstraZeneca 30 20 20 N Does different blood type among people who had side effect relate to the type of vaccinereceived at A=0.025?
2. A psychologist at a private mental hospital was asked to determine whether there was a clear difference in the length of stay for patients with different categories of diagnosis. Looking at the last four patients in each of the three major categories, the results (in terms of weeks of stay) were as follows: Diagnosis Category Affective Disorders Cognitive Disorders Drug-Related Conditions 7 12 8 6 8 10 5 9 12 6 11 10 Using alpha = 0.05, is there a…
In immune.xlsx, some individuals received a treatment of carotenoids (CAROT) and some received no treatment (NO). Carotenoids belong to a class of molecules called isoprenoids, many of them are antioxidants and some of them are vitamins such as vitamin A and its precursor beta-carotene, which is found in carrots. Because of the antioxidant properties of carotenoids the purpose of the study was to check if they have any effect on immunity. The column PHA gives quantitative measuremenst of cell-mediated immunity and the column SRBC gives quantitative measurements of humoral immunity. This is clearly a two-sample (non-paired) design. Therefore, you need to perform a Mann-Whitney-U test to check for differences. Bear in minds that rank assignments in Excel can be quite tricky and, therefore, if you need to do a Mann-Whitney rank assignment it is probably best to do this by hand. 1) What is the rank sum of the PHA data of the individuals, which received carotenoids and what is the…
In immune.xlsx, some individuals received a treatment of carotenoids (CAROT) and some received no treatment (NO). Carotenoids belong to a class of molecules called isoprenoids, many of them are antioxidants and some of them are vitamins such as vitamin A and its precursor beta-carotene, which is found in carrots. Because of the antioxidant properties of carotenoids the purpose of the study was to check if they have any effect on immunity. The column PHA gives quantitative measuremenst of cell-mediated immunity and the column SRBC gives quantitative measurements of humoral immunity. This is clearly a two-sample (non-paired) design. Therefore, you need to perform a Mann-Whitney-U test to check for differences. Bear in minds that rank assignments in Excel can be quite tricky and, therefore, if you need to do a Mann-Whitney rank assignment it is probably best to do this by hand. 1) What is the rank sum of the SRBC data of the individuals, which received carotenoids and rank sum of…
An automotive engineer is investigating two different types of metering devices for an electronic fuel injection system to determine whether they differ in their fuel mileage performance. The system is installed on 10 different cars, and a test is run with each metering device on each car. The data is provided below: Metering Device Car 1 2 1 17.6 16.8 2 19.4 20.0 3 18.2 17.6 4 17.1 16.4 5 15.3 16.0 6 15.9 15.9 7 16.3 16.5 8 18.0 18.4 9 17.3 16.4 10 19.1 20.1 Is there a significant difference between the means of the two metering devices? Use . Interpret the result in the context of the problem. An article in the journal Hazardous Waste and Hazardous Materials (Vol. 6, 1989) reported the results of an analysis of the weight of calcium in standard cement and cement doped with lead. Reduced levels of calcium would indicate that the hydration mechanism in the cement is blocked…
The manufacturer of a gasoline additive claims that the use of this additive increases’gasoline mileage. A random sample of 6 cars was selected, and these cars were drivenfor one week without the gasoline additive and then for one week with the additive.The following table gives the mileage (in miles per gallon) for these cars with andwithout the additive: car 1 2 3 4 5 6 mileage without additive 24.6 28.3 18.9 23.7 15.4 29.5 mileage with additive 26.3 31.7 18.2 25.3 18.3 30.9 Assuming mileage are normally distributed, can you conclude that the use of thegasoline additive increases mileage at the 2.5% significance level?