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Hypothesis Testing

Test hypothesis, decision rule, value of test statistic

The mean income per person in the United States is $41,500, and the distribution of incomes follows a normal distribution. A random sample of 10 residents of Wilmington, Delaware, had a mean of $47,500 with a standard deviation of $10,600. At the .01 level of significance, is that enough evidence to conclude that residents of Wi

Hypothesis Testing of Population Proportion and Level of Significance

According to the National Institute for Occupational Safety and Health, job stress poses a major threat to the health of workers. A national survey of restaurant employees found that 75% said that job stress had a negative impact on their personal lives. A sample of 100 employees of a restaurant chain finds that 68 answer Yes

Test four colors of sticky boards in a field of oats to trap beetles

The presence of harmful insects in farm fields is detected by erecting boards covered with a sticky substance and then examining the insects trapped on the board. To investigate which colors are most attractive to cereal leaf beetles, researchers placed six boards of each of four colors in a field of oats. The data is listed bel


The Computer Anxiety Rating Scale (CARS) measures an individual's level of computer anxiety, on a scale from 20 ( no anxiety) to 100 (highest level of anxiety). Researchers at Miami University administered CARS to 172 business students. One of the objectives of the study was to determine whether there is a difference between th

Critical Value, Calculated Value, and P-Value

See the attached file. A national sales manager of an automobile supply chain claims that monthly sales of auto parts at on of the district office are an average of $5,285. The district manager believes the amount is too high. They authorize you to settle the dispute. You take a simple random sample (n=25) of the sales receip

Hypothesis testing : T test.

32. What probability value would be needed to complete the following probability distribution? x -5 -1 0 1 4 P(x) 0.13 0.25 0.12 0.30 25. An apartment building has the following apartments: 1 bedroom 2 bedroom 3 bedroom 1st floor 3 1 1 2nd floor 2 2 2 3rd floor 1 4 1 If an apartment is selected at random, what is

Levels of Measurement in Statistics

How do you classify statistical findings in order of power: nominal, ordinal, interval, and ratio? Give example by making up values. Use example of Rancidity values in Rice Bran. Thanks


31. A new weight-watching company, Weight Reducers International, advertises that those who join will lose, on the average, 10 pounds the first two weeks with a standard deviation of 2.8 pounds. A random sample of 50 people who joined the new weight reduction program revealed the mean loss to be 9 pounds. At the .05 level of

Statistics Problems: T-value, Z-value and Null Hypothesis

1. A random sample of size 81 is taken from a large population, measuring the time it takes to complete a driver's license examination. The sample mean was found to be 43 minutes, and the sample standard deviation 5.71 minutes. Construct a 95% confidence interval around the sample mean. Be sure to show whether you use the t- or

Statistics and probability of the crew on the Titanic

The table below summarizes the fate of the passengers and crew. A common rule of the sea is that when a ship is threatened with sinking, women and children are the first to be saved. Fate of passengers and crew on the Titanic: ____________________________________________________________ Men

Mean Driving Distance

Callaway Golf is one of the leading golf equipment manufacturers in the United States. The company's R&D department has created three new golf ball designs (GB1, GB2 and GB3) that result in reduced air drag and thereby increase driving distance. The company currently has three distinct brands of driver clubs: FX1, FX2 and FX3.

Golf Cental: Do golf club brands differ in mean distance

See data file attached. You are the research director at the golf magazine 'Golf Central'. Your magazine decides to test three different brands of 3-iron golf clubs and rate the three brands with regards to the distance. You randomly recruit 5 golfers to test each of the three brands of 3-iron clubs. Each golfer uses all thr

Data analysis for a financial services company: Mean revenue under marketed plan

The financial data file is attached but you need spss to open the file. Data analysis for a financial services company. There are three different Investment Plans that the company could offer to its customers . You are asked to find out if the expected revenue from marketing any one of these plans is different from the other

Statistics: Multiple regression model; difference between two means

Please choose the correct answers and write briefly why: For a given multiple regression model with three independent variables, the value of the adjusted multiple coefficient of determination is _________ less than R2. a. Always b. Sometimes c. Never d. Can be greater or less depending on the standard error

Hypothesis Testing of Proportions..

See attached file for proper format. Please solve the exercise below in Excel and show your work (and formulas) 1. At α =..05 and .10, test the hypothesis that the proportion of Consumer (CON) industry companies winter quarter profit growth is more than 2% greater than the proportion of Banking (BKG) companies winter

Hypothesis test comparing means: Does one town dine out more than another town?

Restaurateur Danny Valentine is evaluating two, sites, Raymondville and Rosenber, for his next restaurant. Denny suspects that Raymondville residents (population 1) dine out more often (number of times per month) than Rosenberg residents (population 2). Denny commissions a market survey to test his hypothesis. The market

Statistics: Means of independent populations

Please select the correct answer and explain briefly why: 1. In order to test the effectiveness of a drug called XZR designed to reduce cholesterol levels, 20 heart patients' cholesterol levels are measured before they are given the drug. The same 20 patients use XZR for two continuous months. After two months of continuous u

Writing null and research hypotheses

Please help me with this problem: Sixteen juvenile rats were treated with the drug Naloxone (pairs 1,3,7,8) or, as a placebo control, Saline (pairs 2,4,5,6) and then observed for their play and non-play behavior in an open field for 1.5 minutes. The goal of the research was to test the idea that the inhibition of endogenous o

Hypothesis Testing: Intrinsic by Gender & Extrinsic by Position

TEST #1 Intrinsic by gender Perform the following two-tailed hypothesis test, using a .05 significance level: - State the null and an alternate statement for the test - Use Microsoft Excel (Data Analysis Tools) to process your data and run the appropriate test. Copy and paste the results of the output to your report in Mic

Hypothesis Testing of Proportion..

Please solve the exercise below and show your work in Excel (and formulas). In an early study, researchers at an Ivy University found that 33% of the freshmen had received at least one A in their first semester. Administrators are concerned that grade inflation has caused this percentage to increase. In a more recent study, o

Test manager's claim at 5% and 1% significance level tests

Please solve the exercise below in Excel and show your work and formulas used. The average waiting time per customer at a fast food restaurant has been 7.5 minutes. The customer waiting time has a normal distribution. The manager claims that the use of a new cashier system will decrease the average customer waiting time in th

Statistical Modeling and Analysis: State the Hypotheses

See attached files. Statistical analysis and presentation of results from a complex data set about ladybirds. You are given a complex data set on the variation of ladybirds This data can be used to examine a range of possible hypotheses. Your task is to state produce a succinct report on this data. Your report

Research Design Statistical Procedures

Research Design. Assume that you are going to conduct an experimental study related to your research question. What statistical procedures would you need to use to accept or deny your hypotheses? Support your answer with references to statistical manuals. You will need to convince the professor that your choices are the best

Hypothesis testing for data of salaries of technology professionals

See attached file using SPSS software to open the .sav file to view data. The data in the table, obtained from Business Week's (June 22, 2006) technology section, represents typical salaries of technology professionals in 13 metropolitan areas for 2003 and 2005. Suppose you want to determine if the mean salary of technology