Exam 1: What Is Statistics

In a sample of 350 students selected from a large college of business,25% are found to be marketing majors.The 25% is a statistic.

The significance level of a statistical inference measures:

A resort employs 3,500 managers and staff.To ascertain their employees' opinions of a proposed health insurance plan,350 employees are surveyed at random.The proportion of the 350 employees who favor the health insurance plan represents a parameter in this scenario.

A company has developed a new power cell and wants to estimate its average lifetime.A random sample of 650 power cells is tested and the average lifetime of this sample is found to be 315 hours.The 315 hours is the value of a:

A descriptive measure of a population is called a parameter.

The confidence level is the proportion of times that an estimating procedure will be wrong in the long run.

A descriptive measure that is computed from a population is called a:

You take a random sample to estimate a population mean and your results have a confidence level of 80%.That means the process you used will give you correct results 80% of the time.

Briefly describe the difference between a population and a sample and give an example of each.

The Human Resources Director of a large hospital wants to determine the percentage of all employees who favor a newly proposed benefits package.He selects 300 employees at random and finds that 85% approve the newly proposed package.The percentage of all employees of this company who favor the newly proposed package is a(n)____________________.

Which of the following represents a population,as opposed to a sample?

A descriptive measure of a sample is called a parameter.

The significance level measures the proportion of the time an inference about a population will be correct in the long run.

The Human Resources Director at Illinois State University wishes to develop an employee pension package.To get an idea of what components of a pension package are most important,he selects 525 employees at random and asks them for their opinions.The group of all employees at ISU is known as the ____________________.

The Human Resources Director at Florida Atlantic University wishes to develop an employee benefits package.To get an idea of what components of a benefits package are most important,he selects 350 employees at random and asks them for their opinions.Numerically summarizing the preferences of these 350 employees is an example of doing ____________________ statistics.

The Surgeon General wanted to study malpractice litigation in Chicago.A sample of 32,000 medical records was selected from all 3.5 million patients who were discharged during the year 2011.Using the information from the sample to make conclusions about malpractice litigation in Chicago is an example of doing ____________________ statistics.

A descriptive measure that is computed from a sample is called a:

A random sample of 100 students is taken at LearnAll University and it's found that their average GPA is 3.1.If this information is used to help estimate the average GPA for all students at LearnAll University,which branch of statistics was applied?

The owner of a large manufacturing company wishes to develop a new employee health benefits package.He selects 500 employees at random and asks them about their preferences regarding their current health benefits package.The 500 employees selected is a(n)____________________.