Using Statistics to Gain InformationSTUDENT ACTIVITY ONE

Work collaboratively through the slideshow.

Random SamplingRepresentative Samples

Populations

Vocabulary to know….Population – the entire collection of people or things that you are interested in

Sample – a subset of some of the units in the population

Random Sample – a subset taken from a population in a random way. This would be a sample set up so that each member of the target population has an equally likely chance of occurring.

Representative Sample - This is a sample in which every member of the population has an equal chance of being included in the sample. Random sampling is the best way to produce a representative sample that will support valid inferences.

So…Dillard Drive Middle School is considering the following locations for a 7th grade Field Trip: science museum, state park or Ballet Company. The principal wants to survey a sample of students to find which location the 7th graders would prefer. Discuss whether the following are good surveys and why they are or why they are not.

•The principal surveys the members of the science club for the sample•The principal surveys every tenth student to walk into the middle school on a given morning.•The principal surveys a group of randomly selected 7th grade girls.

What is YOUR suggestion for a good survey to determine the location that 7th Grade

students would prefer?We think……

Discuss and answer whether the sample is representative of the population. What is the population? You decide!

You want to know what type of music students at your school like the best. You ask a group of your friends which music

they like. Population:

Is sample representative?

You want to know which type of food students at Apex High like best. You ask every20th student in the Apex

High yearbook.Population:

Is sample representative?

You want to know how many hours 6th graders in your school spend on the computer each day. You ask random

students as they leave for the busses and carpool.

Population: Is sample representative?

You want to know how many hours students in middle school exercise

each week. You send a survey out to every middle school athletic team in

Wake County. Population:

Is sample representative?

Suppose you are taking a poll of students in your grade to see whom they are going to select in the election for student council president. Describe one way

you could find a sample that is representative of the population.

Suppose you are taking a poll of students in your grade to see whom they are going to select in the election for student council president. Describe one way

you could find a sample that is representative of the population.

Enter your description here:

The owners of Bear Rock Café and Bloomsbury Bistro have been discussing the types of customers they serve. In their discussion they found that they should learn more about the types of customers that dine at their restaurants so they each decided to conduct a survey to find their customer’s ages and the price they would expect to pay for an entrée. Should they survey the first 15 women dressed in business attire? Is this sample representative of the population?

Should they survey every 5th customer at lunch? Is this sample representative of the population?

Describe a survey method that you think would give the restaurant owners a representative sample of the population.

The table below shows age data the owners of each restaurant gathered from a representative sample.

34 41 45 67 23 19 45 34 56 63

29 17 23 18 14 28 21 24Bloomsbury Bistro

Bear Rock Cafe

What questions might you ask about this data collection?

What is the mean age for each restaurant’s customers according to the data?

What does this mean tell you about the customers that each restaurant attracts?

The owners of these two restaurants are deciding how to advertise their restaurants. They want to advertise to the group of customers that they expect will want to dine with them. Give some recommendations to each owner about how and where they should advertise….