Exam 1: What Is Statistics

You ask five of your classmates about their height. On the basis of this information, you state that the average height of the students in the sample is 170 cm. Which of the following is this an example of?

A businessman who is running for a vacant city council seat with 2000 registered voters conducts a survey. In the survey, 200 of the 300 registered voters interviewed say they plan to vote for him. A.What proportion of the respondents plans to vote for this businessman? B.What is the population of interest? C.What is the sample? D.Is your answer in part A above a parameter or a statistic?

Descriptive statistics deals with methods of:

Which of the following statements is true?

Statistical inference is the process of making an estimate, prediction or decision about a population, based on sample data.

Consider the population of all pencil manufacturers in the world. Describe any four examples of possible samples that could be taken from this population.

A local cable TV system using a sample of 500 subscribers finds that 40% of these subscribers watch a premium channel at least once per day. This is an example of statistical inference as opposed to descriptive statistics.

Which of the following is the goal of descriptive statistics? A.To summarise data. B.To display aspects of the collected data. C.To summarise data and display aspects of the collected data. D.To estimate characteristics of the population.

A summary measure that is computed from a sample to describe a characteristic of the population is called a statistic.

Which of the following best describes the data that is collected in a statistical study for only a portion or subset of all elements of interest?

A manufacturer of televisions claims that fewer than 3% of their products are defective. When 100 televisions were drawn from a large production run, 10% were found to be defective. A.What is the population of interest? B.What is the sample? C.What is the parameter? D.What is the statistic? E.Does the value of 3% refer to the parameter or the statistic? F.Is the value of 10% a parameter or a statistic? G.Explain briefly how the statistic can be used to make inferences about the parameter to test the claim.

A summary measure that is computed from a sample to describe a characteristic of the population is called:

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

Define each of the following statistical terms: A.Descriptive statistics. B.Statistical inference. C.Population. D.Sample. E.Parameter.F.Statistic.

A politician who is running for the House of Representatives in the Australian Federal parliament with 70,000 registered voters in her electorate commissions a survey. In the survey, 52% of the 300 registered voters interviewed say they plan to vote for her. The sample is the:

Identify each of the following studies as using either descriptive statistics or inferential statistics. A.Calculating the relative frequency of Holden Commodore SV6 cars passing by your house between 7pm and 8pm this evening. B.Estimating the proportion of households in Melbourne that have at least two dependents, from a random sample of 100 Melbournian households. C.Measuring the fuel efficiency of five brand new Holden Commodore SV6 cars in order to find out whether the average fuel consumption of this make and model is better than 10L/100km. D.Calculating the proportion of female students in a business statistics class. E.Estimating the average age of students at La Trobe University from a sample of 200 randomly selected students.

A summary measure that is computed from a population is called a population parameter.