How do you predict the winner of an election before the election takes place?

In this lesson you will learn how to collect data about a population by identifying a sample of the population.

Let’s Review How many texts do middle school students send in one day? Statistical questions are used to gather data about a population.

Core Lesson That could take a long time…

Core Lesson By surveying a sample of the group, you can make a generalization about the entire group.

The population is the entire group being studied. A sample is part of the population being surveyed.

For example: Predict the winner of the upcoming presidential election Adults walking to work American votersPopulation Sample

Another example: Tracking migration pattern of birds Tagged birds A bird speciesPopulation Sample

In this lesson you have learned how to collect data about a population by identifying a sample of the population.

Guided Practice Identify the population and sample in the following survey: To gauge students’ preference for a new school mascot, the Student Council President surveys her soccer team. Population Sample

Extension Activities Answer the following questions. 1.You are buying ice cream for a party at your school, in which 700 students will attend. How would you use sampling to make a generalization about students’ preferred ice cream flavors? 2.Why not survey all 700 students? 3.Describe the sample you would survey, and explain why you chose that sample.

Investigate the texting habits of middle school students in the United States by conducting a survey in class today. 1.Write the survey question, survey the students in your class, and record the data. 2.Calculate the average number of texts sent. 3.Use the data from your sample to make a generalization about the population. Make sure to identify the population and sample. Extension Activities

Describe a sample of each of the following populations. 1) Stop lights in the United States 2) American politicians 3) Professional athletes 4) Hospital employees Extension Activities

Quick Quiz Identify the population and the sample: 1. A telephone survey is given to 2,000 randomly selected families in order to predict the average amount of money American families spend on groceries each week. 2. To determine the number of students who carry backpacks in school, Tina collects data on the first 100 students who enter the building.

Let’s Review How many texts do middle school students send in one day? Mean Median Mode Range Interquartile Range Mean Absolute Deviation Statistical measures are then used to analyze that data.