Determine the type of sampling used (simple random, stratified, systematic, cluster, or convenience). а. А soccer coach selects six players from a group of boys aged eight to ten, seven players from a group of boys aged 11 to 12, and three players from a group of boys aged 13 to 14 to form a recreational soccer team. b. A pollster interviews all human resource personnel in five different high tech companies. С. А high school educational researcher interviews 50 high school female teachers and 50 high school male teachers.

A company has been rating television programs for more than 60 years. It uses several sampling​ procedures, but its main one is to track the viewing patterns of​ 20,000 households. These contain more than​ 45,000 people and are chosen to form a cross-section of the overall population. The households represent various​ locations, ethnic​ groups, and income brackets. The data gathered from the sample of​ 20,000 households are used to draw inferences about the population of all households in the United States. Complete parts​ (a) and​ (b) below. What strata are used in the​ sample? Choose the correct answer below.     A. The various​ locations, ethnic​ groups, and income brackets that are represented   B. The various sampling procedures and viewing patterns   C. The number of households and people that are chosen   D. The television ratings Why is it important to have a stratified sample for these​ ratings? Choose the correct answer below.     A. Stratified…

The computer science department is making a new recruitment poster for computer science majors and would like to include information about the average salary of a software developer on the Treasure Coast. To estimate the average salary of a software developer, someone from the department collected a random sample of 10 local software developers. Their salaries are listed below. Assume that the salaries of all software developers on the Treasure Coast are normally distributed. 81,174 82,435 82,598 81,131 82,791 82,241 81,292 82,051 81,041 82,808 Determine the point estimate, ¯xx¯ and the sample standard deviation, ss. Round the solutions to four decimal places, if necessary.¯x=x¯=s=s=Using a 99.9% confidence level, determine the margin of error, EE, and a confidence interval for the average salary of a software developer on the Treasure Coast. Report the confidence interval using interval notation. Round solutions to two decimal places, if necessary.The margin of error is…

Determine whether the sampling method described below appears to be sound or is flawed. In a survey of 337 subjects, each was asked about the importance of the appearance of a job applicant. The survey subjects were human resource professionals who randomly selected by pollsters from a reputable market research firm. It is flawed because it is from a small sample. It appears to be sound because it is a census. It is flawed because it is a voluntary response sample. It appears to be sound because the data are not biased in any way.