Statistical vs. practical signficance Consider the following statement and discuss its implications. 'It is possible for a statistically significant result to be of no particular practical significance, depending on the context of the analysis.' a. Use a concrete example to illustrate your point(s). b. Explain the di
A telephone company estimates that 30% of its customers are interested in high-speed Internet Service. To test this estimate, a random sample of 100 customers were selected and the results showed that 25 were interested in high-speed Internet Service. Can it be concluded that the percentage of customers interested in high-speed
A psychologist believes that if classical music is played during a test, test scores will increase. In the past, the mean test score was 60. A random sample of 49 individuals wrote the test while classical music was in the background. The sample results showed a mean test score of 62 and a standard deviation of 6.3. Using a 5% l
A study conducted last year indicated that adults spent an average of 14 hours on household chores during the weekend. A research group wishes to determine if the average hours spent o household chores during the weekend this year is different from the 14 hours of last year. Consequently, the research group selects a random samp
Pollsters just report the results of hypothesis tests that show statistical significance but not those in which there was insufficient evidence. Therefore, I would like the pollster to provide both the good and bad results. This is because, as students of Statistics, we should remember that if there is insufficient evidence to r
1. The average U.S. family includes 3.13 persons. To determine whether families in her city tend to be smaller in size compared to those across the United States, a city council member selects a simple random sample of 25 families. She finds the average number of persons in a family to be 2.78, with a standard deviation of 0.89.
Why is it important that a sample be random and representative when conducting hypothesis testing?
The Video Game Satisfaction Rating Case Please help with the following problem. Recall that "very satisfied" customers give the XYZ-Box video game system a rating that is at least 42. Suppose that the manufacturer of the XYZ- Box wishes to use the random sample of 65 satisfaction ratings to provide evidence supporting the
For each problem below, answer the following 1. State the Ho 2. State the H1 3. Find the critical value 4. Determine the test statistic. Explain 5. State the decision rule 6. Show the decision rule graphically 7. Determine the computed value of the test statistic 8. Determine the p-value 9. What is your decis
A research firm wants to compare the miles per gallon of unleaded regular, mid-grade, and super grades of gasoline. They drive the same car under approximately similar driving conditions and changing out the type of gasoline used. At the .05 significance level, is there a difference in gas mileage for the different types of gas?
Please see attached document. 1) The statement that determines if the null hypothesis is rejected or not is called the A. critical value B. alternate hypothesis C. test statistic D. decision rule 2) What are the critical z-values for a two-tailed hypothesis test if the significant level = 0.01
Chapter 10 1. Rutter Nursery Company packages its pine bark mulch in 50-pounds bags. From a long history, the production department reports that the distribution of the bag weights follows the normal distribution and the standard deviation of this process is 3 pounds per bag. At the end of each day, Jeff Rutter, the production
1. What is the difference between a binomial distribution and a normal distribution? Provide an example that illustrates the difference. 2. What are the five steps of hypothesis testing... list each? 3. Provide one example of probability sampling. 4. Provide one example of non-probability sampling.
See attached file. Hypothesis Testing Examine the given statement, then express the null hypothesis H0 and alternative hypothesis H1 in symbolic form. Be sure to use the correct symbol (μ , p ,σ) for the indicated parameter. 1. The majority of college students own a vehicle. 2. Th
See attached files. SPSS Exercise Questions If you know how to operate SPSS, the assignment is fairly simple. The instructions are long, because I have included the scenarios as well. All datasets will be automatically entered into the SPSS by access the link below. I just need the measures ran and a synopsis to show cl
Please see attached file for data. Question: A sportswear manufacturer wishes to investigate the relationship between the level of advertising, coupon value and sales. The manufacturer advertises several times a month and includes a manufacturer coupon (in dollars) with each advertisement. The value of the coupon remains the
See attached files. Assume all data/output is normal. 4. The manager of the customer service department at Buy.com was concerned about the performance of their call center employees. He found that average call times were higher than industry average. The manager decides to invest in a program to train his call center emplo
MLB 1 A study was conducted to determine if persons in surburan district I have a different mean income from those in district II. A random sample of 50 homeowners was taken in district I. Although 50 homeowners were to be interviewed in district II also, one person refused to provide the information requested. So only 49 ob
Please state the hypothesis (statistically) and explain the type (the name) of test I need to run. Please do not do anything else on this one. 1) An organic food retailer sells three types of natural yogurt: plain, low fat and fat-free. The retailer wishes to expand the shelf space allocated to yogurt and decides to allocate
Consumption of Saturated Fat: A nutritionist claims that the proportion of females who consume too much saturated fat is lower than the proportion of males who consume too much saturated fat. In interviews with 513 randomly selected females, she determines that 300 consume too much saturated fat. In interviews with 564 randomly
2. In August 2003, 56% of employed adults in the United States reported that basic mathematical skills were critical or very important to their job. The supervisor of the job placement office at a 4-year college thinks this percentage has increased due to increased use of technology in the workplace. He takes a random sample of
1. National data show that, on average, college freshman spend 7.5 hours a week going to parties. President DeRosa doesn't believe that these figures apply at his school; he thinks freshman at his school party less. He takes a simple random sample of 50 freshmen and interviews them. He asks you to analyze his sample data. You de
Suppose the federal government gives a substantial tax break to automakers producing midsized cars that get a mean mileage exceeding 31 MPG. A sample of 49 mileages has a mean x-bar of 31.350 and a standard deviation of s=0.799. Let u be the midsize car's mean mileage. Assume alpha=0.01 a) The following questions, represen
1.A sample of 64 college students are asked their weekly (at school) expenses during the fall term. The enquire resulted in a mean of $55 with a standard deviation of $12. Construct a 95% confidence interval for the mean expense for all the students in the school. a. Value from the table ____________ b. The confidence i
How to determine the difference between men and women regarding ACT scores and college GPA Show my findings Describe what they mean ACT Score College GPA Gender 28 1.72 M 25 3.51 M 21 2.45 F 19 2.85 F 22 2.84 M 15 3.46 F 26 1.97 F 20 3.47 F 23 3.47 M 22 4 M 16 2.94 F 21 1.9 F 23 3.25 M 17 3.23 F 25 3.51 M 19
See attached file. Using Data set 'G', choose the dependent variable (the response variable to be 'explained') and the independent variable (the predictor or explanatory variable) as you judge appropriate. Use a spreadsheet or a statistical package (e.g., MegaStat or MINITAB) to obtain the bivariate regression and required gr
See attached file. Hypothesis - Null & Alternative, p-value for F-test (ANOVA) - How to determine significance difference in means 1) An investor wants to know if a difference exists, at a significance level of 0.05, between home prices in three subdivisions. Independent samples of homes from each of the three subdivis
The Rocky Mountain district sales manager of Rath Publishing, Inc., a college textbook publishing company, claims that the sales representatives make an average of 36 sales calls per week on professors. Several reps say that this estimate is too low. To investigate, a random sample of 32 sales representatives reveals that the me
1) If the correlation coefficient r is equal to 0.57, find the coefficient of determination. a) 0.68 b) 0.75 c) 0.45 d) 0.32 2) The prediction interval around y' for a specific x is a) A confidence interval for the true mean value of the y values that correspond to that x b) The value of y used to calculate the slo
According to news reports, Las Vegas betting parlors increased the number of proposition (prop) bets available to gamblers for this year's Super Bowl (Example: Which team will be the first to suspend a starting player for a team rules violation?). It is believed that the mean number of prop bets per typical gambler is normally