1. Why is sampling strategy important? Please provide one or two examples from your work or past experience? 2. What is the difference between the population of the study and the sampling frame? Provide an example to support your response. 3. Non-probability (purposive, quota) and probability (simply random, cluster) are t
2. We wish to compare the average sales in two shops, to see if the population mean of the first one is higher than the second one. One shop had 100 sales averaging $94, with a standard deviation of $40. The other had 64 sales averaging $86, with a standard deviation of $24. At an alpha level of 5%, can we conclude that the firs
1. We want to know if men and women perform differently on statistics test. The average of 15 mens scores was 76. The average of 10 womans scores was 83. The standard deviation in both cases is 10. a) what are the null and alternate hypothesis? b) What kind of test should be used? c) Is it a one tailed or two tailed test? Why
A trans-oceanic airline conducted a study to determine whether the average weight of baggage checked by a passenger differs significantly from 45 pounds. A random sample of 25 passenger baggages recorded a mean weight of 43.5 pounds with a standard deviation 6 pounds. Can the airline conclude that the mean weight of checked bagg
What is the difference between the null and alternative hypothesis statements in one tailed and two tailed tests? How can manufacturing companies use the standard normal distribution to determine quality control of their products?
What is the difference between the null and alternative hypothesis statements in one tailed and two tailed tests? How can manufacturing companies use the standard normal distribution to determine quality control of their products?
A trans-oceanic airline conducted a study to determine whether the average weight of baggage checked by a passenger differs significantly from 45 pounds. A random sample of 25 passenger baggages recorded a mean weight of 43.5 pounds with a standard deviation 6 pounds. Can the airline conclude that the mean weight of checked ba
1) If a test of a hypothesis has a Type 1 error probability (a) of 0.01, we mean: A) if the null hypothesis is true, we don't reject it 1% of 0.01 of the time(B) if the null hypothesis is true, we reject it 1% of the time (C) if the null hypothesis is false, we don't reject it 1% of the time (D) if the null hypothesis is false
In order to monitor the ecological health of the Florida Everglades, various measurements are recorded at different times. The bottom temperatures are recorded at the Garfield Bight station and a mean temperature of 30.4°C is obtained for the temperatures recorded on 61 different days. Assuming that σ = 1.7°C, test the cl
The United States Golf Association requires that golf balls have a diameter that is 1.68 inches. An engineer for the USGA wishes to determine whether Maxfli XS golf balls have a mean diameter which is different from the 1.68. A random sample of 12 Maxfli XS golf balls was chosen. The mean diameter of the sample was 1.6809 with a
According to the U.S. federal Highway Administration, the mean number of miles driven annually is µ=12,200. An insurance agent in Montana believes that the mean number of miles driven by the residents of his state is higher than the national average. A random sample of 35 drivers is taken from the list of registered drivers in
Attached is an excel sheet with all data required for a 5 step hypothesis test. Please use a nonparametric test. (if this needs to be changed to MEDIAN vs MEAN to meet the requirements, please do so. I am confused on the differences of the types of tests. Please help!! Hypothesis Statement: H0: There is no significant d
Please help with this problem showing work.
Compares the sample statistics with parameters expected for a normal distribution. Since the mean and standard deviation were fitted from the data, they tell us nothing. The median 4.808) is slightly less than the mean (4.844), but the skewness coefficient (0.14) is fairly close to the value (0.00 that would be expected in a sym
I'm having trouble understanding the following question can you please explain? 1) The owner of an Internet video supplier, Netflix, has conducted a study of habits of online customers. In particular she wants to estimate the average number of videos checked out each month. Before she can determine the sample size she will ne
A random sample of 51 observations was selected from a normally distributed population. The sample mean was = 88.6, and the sample variance was s2 = 38.2. Does the sample show sufficient reason to conclude that the population standard deviation is not equal to 8 at the 0.05 level of significance? Use the p-value method. A re
Most computer laptops use a rechargeable lithium-ion battery. However, with brighter computer displays and more powerful chips, batteries are not lasting any longer. to determine the avg. number of hrs of use that a college student gets on a laptop before the batteries fail, 51 students were randomly selected, and values of the
The null and alternate the hypotheses are: H0: µ1 = µ2 H1: µ1 ≠ µ2 A random sample of 10 observations from one population revealed a sample mean of 23 and a sample deviation of 4. A random sample of 8 observations from another population revealed a sample mean of 26 and a sample standard deviation of 5. At the
Given the following hypothesis: H0: µ =/>20 H1: µ<20 A random sample of five resulted in the following values: 18, 15, 12, 19, and 21. Using the .01 significance level, can we conclude the population mean is less than 20? a. State the decision rule. b. Compute the value of the test statistic. c. What is your
4. A neurologist wants to detect whether the mean response time for drug-injected rats differs from a control group not injected. The control group has the mean response time of 1.2 seconds. 100 rats are randomly chosen and injected with a unit dose of the drug. The average response time for the injected rats is 1.05 seconds wit
A study of cats and dogs found that 11 of 50 cats and 21 of 50 dogs slept more than 10 hours per day. At the .05 level of significance, is there sufficient evidence to conclude that a difference exists between the proportion of cats and the proportion of dogs that sleep more than 10 hours per day? A)No, there is not suffici
A dietician investigated whether apples washed in hot water or in cold water turned brown at different rates when exposed to air. She took 13 random apples and cut each in half. She washed one half of each apple in hot water and the other half in cold water, and then put both halves out in a tray. Her results (in hours until tu
Please refer to the attached Excel file.
A random sample of 10 observations from one population revealed a sample mean of 23 and a sample deviation of 4. A random sample of 8 observations from another population revealed a sample mean of 26 and a sample standard deviation of 5. At the .05 significance level, is there a difference between the population means?
Gibbs Baby Food Company wishes to compare the weight gain of infants using its brand versus its competitor's. A sample of 40 babies using the Gibbs products revealed a mean weight gain of 7.6 pounds in the first three months after birth. For the Gibbs brand the population standard deviation of the sample is 2.3 pounds. A sample
1.Explain how you decide what statement goes into the null hypothesis and what statement go into the alternative hypothesis. 2. What is a critical value? 3. What is Alpha and how is it related to the p-value?
Given the following hypothesis: H0: µ≥20 H1: µ<20 A random sample of five resulted in the following values: 18, 15, 12, 19, and 21. Using the .01 significance level, can we conclude the population mean is less than 20? a. State the decision rule. b. Compute the value of the test statistic. c. What is your d
Given the following hypothesis: H0: µ<10 H1: µ>10 For a random sample of 10 observations, the sample mean was 12 and the sample standard deviation 3. Using the .05 significance level: a. State the decision rule. b. Compute the value of the test statistic. c. What is your decision regarding the null hypothesis?
The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the average, to assemble a cart. The mean assembly time for a random sample of 24 carts, using the new method, was 40.6 minutes, and the standard deviation of the sample was 2.7 minutes. Using
The president of the American Insurance Institute wants to compare the yearly costs of auto insurance offered by two leading companies. He selects a sample of 15 families, some with only a single insured driver, others with several teenage drivers, and pays each family a stipend to contact the two companies and ask for a price q