9 A, #2: A magazine reported the results of a survey in which readers were asked to send in their responses to several questions regarding anger. Consider the reported results to the question: How long do you usually stay angry?

1. What type of sampling technique was used for this survey?
2. What type of biases may be present in the responses?
3. Is \(22 \%\) a reasonable estimate of the proportion of all Americans who hold a grudge indefinitely? Explain.

9 D, #4: A social researcher in Florida wants to determine the average number of children per family in the state.

1. What is the population of interest?
2. What variable will be measured?
3. What level of measurement is the variable of interest?
4. Discuss the steps that would be necessary for each of the following sampling methods:

1. Simple random sampling
2. Cluster sampling
3. Stratified sampling

e. What sampling method do you believe would be most cost effective?

9 D, #5: A stock analyst wants to estimate the average yearly earnings of stocks on the New York Stock Exchange.

1. What is the population of interest?
2. Discuss the steps necessary to apply each of the following sampling methods:

1. Simple random sampling
2. Cluster sampling
3. Stratified sampling

10 A, #2: Find \({{z}_{\alpha /2}}\) for levels of \(\alpha \)

1. \(\alpha =0.04\)
2. \(\alpha =0.02\)
3. \(\alpha =0.08\)

10 B, #6 : Construct an \(80 \%\) confidence interval for the mean of a normal population assuming that the values listed below comprise a random sample taken from the population. The population standard deviation is unknown.

10 C, #2 : A computer software company would like to estimate how long it will take a beginner to become proficient at creating a graph using their new spreadsheet package. Past experience has indicated that the time required for a beginner to become proficient with a particular function of the new software product has an approximately a normal distribution with a standard deviation of 15 minutes. Find the sample size necessary to estimate the average time required for a beginner to become proficient at creating a graph with the new spreadsheet package to within 5 minutes with \(95 \%\) confidence.

10 E, #2: Researchers working in a remote area of Africa feel that \(40 \%\) of the families in the area are without adequate drinking water either through contamination or unavailability. What sample size will be necessary to estimate the percent without adequate water to within \(5 \%\) with \(95 \%\) confidence?

11 AQ, #2: For the following situations, identify the appropriate \(H_{0}\) and \(H_{a}\) and state what the consequences would be for Type I and Type II errors.

1. A company which manufactures one-half inch bolts selects a random sample of bolts to determine if the diameter of the bolts differs significantly from the required one-half inch.
2. A company which manufactures safety flares randomly selects 100 flares to determine if the flares last at least three hours on average.
3. A consumer group believes that a new sports coupe gets significantly less miles to the gallon than advertised on the sales sticker. To confirm this belief, they randomly select several of the new coupes and measure the miles per gallon.

Price: $18.82

Solution: The downloadable solution consists of 7 pages, 1182 words and 2 charts.
Deliverable: Word Document