1. Bias & Sample Types Unit Four: Inferences, MCC7.SP 1 What is bias and how can it be avoided? What are the different types of samples?

2. Language of the Standards A local radio station is trying to determine the most popular song this week. They have 5,000 listeners throughout the area. The station decides to send a postcard to 1,000 listeners and asks them to respond. Identify the following: Population = Sample = Question = Data = Did they take a census or a survey? -

3. Language of the Standards Leslie plays tennis and she wants to know how many people in her town also play tennis. How can she find the number of tennis players in her town? On Saturday, she can go to a tennis court and count how many play there. She can call every hundredth person in the phone book. She can post a survey on the internet. On Saturday, she can stand outside the grocery store and ask each person entering the store.

4. Language of the Standards Bias: an unfair preference for or dislike of something Jose, Chandler and Ambria are running for class president. The newspaper is conducting a survey to predict who will win the election. What question should the newspaper ask to predict who will win? Are you going to vote for Ambria? Are you going to vote for Jose despite his questionable character? Are you going to vote for Chandler who was the football quarterback or someone else? Which choice are you going to make for class president?

5. Is there Bias in each scenario? The first 5 people leaving a movie theater at a sneak preview were asked how they liked the movie. An eighth-grade student council member polls classmates about a new school mascot. A television reporter asks people on downtown streets if they support a new city subway system. Eighth-grade students with a 4.0 GPA or higher were polled to determine how long middle school students study each day. People attending a baseball game were asked if they support the construction of a new stadium in the city. A record store manager asks customers who make a purchase how many hours of music they listen to each day.

6. Language of the Standards Convenience Sample: Using the most available people to get quick results. Random Sample: Each person has an equal chance of being chosen. Voluntary Response: People chose to participate. -

7. What type of sample is it? Ms. Searcy has 36 students in her English class. The students are seated in 6 rows. The students in each row are assigned a different number 1 through 6. Ms. Searcy rolls a 6-sided number cube to select a row. She rolls it again to select one of the students in that row. The selected student is given a survey about Ms. Searcy's English class. Mr. Jensen gives a stack of surveys about the school lunch to the students in his 5th period class. Professor Samson leaves a stack of surveys on a table and invites each student to fill one out as they leave class. The survey asks about their satisfaction with the class. Only 22 out of the 28 students complete the survey? -

8. Is it a Random Sample The first 50 nurses at a nursing convention write their names on slips of paper and place them in a drawing box. After the box is shaken, 20 names are pulled from the box and each person chosen completes a survey about their transportation to the convention.