Population vs Sample/Biased vs Unbiased

​Statistics- the study of data

Population- an enite group of people or objects in which we want information about

Example: The students at RCHS

Sample- part or group of the population in which we collect information from

Example: The students on the RCHS track team.

A sample that is not representative of the larger population and usually favors certain parts of the population

​Biased

-Representative of the larger population

-Selected at random

-Larger enought to provide accurate data

Unbiased

Valid Samples are unbiased

Poll

A mayor wanted to see if the people in his town thought that he was doing a good job. (Identify the population)

• The mayor’s family

• The people who didn’t vote for the mayor

• 216 voters

• The residents of the town

Poll

A mayor wanted to see if the people in his town thought that he was doing a good job. (Identify a valid sample)

• The mayor’s family

• The people who didn’t vote for the mayor

• 216 voters

• The residents of the town

Poll

A musician wanted to see what people who downloaded his last album thought about the songs. (Identify the population)

• Every person who downloaded the album

• 225 girls who downloaded the album

• A selection of 2456 people who downloaded the album

• A selection of people who didn’t download the album

Poll

A musician wanted to see what people who downloaded his last album thought about the songs. (Identify a valid sample)

• Every person who downloaded the album

• 225 girls who downloaded the album

• A selection of 2456 people who downloaded the album

• A selection of people who didn’t download the album

Poll

A gaming website wanted to find out which console its visitors owned.

(Identify the population)

• Visitors over 16

• All of the website visitors

• Visitors with an ‘e’ in their username

• Visitors to the PS4 section

Poll

A gaming website wanted to find out which console its visitors owned.

(Identify a valid sample)

• Visitors over 16

• All of the website visitors

• Visitors with an ‘e’ in their username

• Visitors to the PS4 section

Multiple Choice

Determine whether each sample is biased or unbiased.

Casey surveyed the members of his soccer team to ask them what their favorite sport is.

• Biased

• Unbiased

Multiple Choice

Determine whether each sample is biased or unbiased.

An airline is conducting a survey to determine whether people prefer to check their luggage or carry it on. They ask every 10th person that walks into an airport.

• Biased

• Unbiased

Multiple Choice

Determine whether each sample is biased or unbiased.

Imani would like to approximate the number of students in her school with part-time jobs. She surveys the 28 students in her math class.

• Biased

• Unbiased

Multiple Choice

Determine whether each sample is biased or unbiased.

A school district would like to know what type of communication (email, text, or phone) parents prefer. They survey the parents of the 7th grade students enrolled in the district.

• Biased

• Unbiased