Question

In: Statistics and Probability

The safety director of a large steel mill took samples at random from company records of...

The safety director of a large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place.

Number of Number of
Time Accidents Time Accidents
8 up to 9 a.m. 10 1 up to 2 p.m. 9
9 up to 10 a.m. 19 2 up to 3 p.m. 20
10 up to 11 a.m. 9 3 up to 4 p.m. 6
11 up to 12 p.m. 8 4 up to 5 p.m. 7

Click here for the Excel Data File

Using the goodness-of-fit test and the 0.01 level of significance, determine whether the accidents are evenly distributed throughout the day.

H0: The accidents are evenly distributed throughout the day.   
H1: The accidents are not evenly distributed throughout the day.

State the decision rule, using the 0.01 significance level. (Round your answer to 3 decimal places.)

Compute the value of chi-square. (Round your answer to 3 decimal places.)

What is your decision regarding H0?

Solutions

Expert Solution

H0: The accidents are evenly distributed throughout the day.   
H1: The accidents are not evenly distributed throughout the day.

observed frequencey, O expected proportion expected frequency,E (O-E)²/E
10 0.125 11.00 0.091
19 0.125 11.00 5.818
9 0.125 11.00 0.364
8 0.125 11.00 0.818
9 0.125 11.00 0.364
20 0.125 11.00 7.364
6 0.125 11 2.273
7 0.125 11 1.455

chi square test statistic,X² = Σ(O-E)²/E =   18.545              
                  
level of significance, α=   0.01              
Degree of freedom=k-1=   8   -   1   =   7
                  
P value =   0.0097   [ excel function: =chisq.dist.rt(test-stat,df) ]  
       
Decision: P value < α, Reject Ho                  

............

THANKS

revert back for doubt

please upvote


Related Solutions

The safety director of a large steel mill took samples at random from company records of...
The safety director of a large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place. Number of Number of Time Accidents Time Accidents 8 up to 9 a.m. 10 1 up to 2 p.m. 8 9 up to 10 a.m. 7 2 up to 3 p.m. 8 10 up to 11 a.m. 8 3 up to 4 p.m. 6 11 up to 12 p.m. 22...
A study took random samples from ocean beaches. A total of 40 samples of size 250...
A study took random samples from ocean beaches. A total of 40 samples of size 250 mL were taken, and the mean number of plastic microparticles of sediment was 18.3 with a standard deviation of 8.2. Test for evidence that the mean number of microparticles is different from acceptable levels 15. What are the null and alternative hypotheses for this test?       Calculate the hypothesis test standard error. Calculate the t test statistic. Show all work. Draw/label/shade a curve. Be sure...
The medical director of a large company looks at the medical records of 72 executives between...
The medical director of a large company looks at the medical records of 72 executives between the ages of 35 and 44 years. He finds that the mean systolic blood pressure in this sample is x̅ = 126.1 and the standard deviation is s = 15.2. Assuming the sample is a random sample of all executives in the company, find a 95% confidence interval for µ, the unknown mean blood pressure of all executives in the company.
The weekly output of a steel mill is a uniformly distributed random variable that lies between...
The weekly output of a steel mill is a uniformly distributed random variable that lies between 110 and 175 metirc tons. 1. Compute the probability that the steel mill will produce more than 150 metric tons next week. 2. Determine the probability that the steel mill will produce between 120 and 160 metric tons next week.
Miner extracts iron from the earth. A steel mill converts the iron to steel beams for...
Miner extracts iron from the earth. A steel mill converts the iron to steel beams for use in construction. A construction company uses the steel beams to make a building. Assume that the total product of these firms represents the only components of the building and that they will have no other uses. Complete the following table: can you please provide detail work? Company Product Total Sales Value Added Acme Mining iron ore $100,000 ? Fuller Mill steel beams $175,000...
The management of the Mini Mill Steel Company estimated the following elasticities for a special type...
The management of the Mini Mill Steel Company estimated the following elasticities for a special type of steel: EP 2, 1, and E where x refers to steel XY and Y to aluminum. Next year, the firm would like to increase the price of the steel it sells by 6 percent. The management forecasted that income will rise by 4 percent next year and that the price of aluminum will fall by 2 percent. (a) If the sales this year...
Researchers equipped random samples of 46 male and 58 female students from a large university with...
Researchers equipped random samples of 46 male and 58 female students from a large university with a small device that secretly records sound for a random 30 seconds during each 12.5-minute period over two days. Then they counted the number of words spoken by each subject during each recording period and, from this, estimated how many words per day each subject speaks. The female estimates had a mean of 16,177 words per day with a standard deviation of 7520 words...
two hundred auditors each took their own simple random sample of fifteen values from a large...
two hundred auditors each took their own simple random sample of fifteen values from a large data set of account balances, and each constructed a 90% confidence interval for the mean balance of the entire data set. About how many of the auditors had the true mean for the entire set in their personal confidence interval?
The manager of the dairy section of a large supermarket took a random sample of 250...
The manager of the dairy section of a large supermarket took a random sample of 250 egg cartons and found that 40 cartons had at least one broken egg. (a) Let p be the proportion of egg cartons with at least one broken egg out of the population of all egg cartons stocked by this store. Find a point estimate for p. (b) Find a 90% confidence interval for p. How many egg cartons would the manager need to examine...
2. The manager of the dairy section of a large supermarket took a random sample of...
2. The manager of the dairy section of a large supermarket took a random sample of 250 egg cartons and found that 40 cartons had at least one broken egg. a) Find a 95% confidence interval for p, the proportion of egg cartons that have at least one broken egg. b) Express your confidence interval in words. c) What is the margin of error? d) What sample size would be needed for a margin of error of 3%?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT