1. Do Now
For your senior project, you are studying first generation college graduates. You are interested in knowing what percent of KIPP students will be the first person in their family to attend college. In order to conduct your study, you will ask 50 KDCA students if their parents or grandparents attended college.
Identify the individuals and variables of interest.
Identify the population and the sample.
Is this an experiment, observational study, or sample survey?

2. Sampling Methods
Unit 1: Univariate Data

3. Objectives
Identify method of reliable sampling and others ways to reduce bias and variability
Demonstrate mastery on Illuminate Quiz 

4. Sampling
Sample should be representative of the population in order to make inferences.
This means the sample must be as randomly chosen as possible.
A sample is biased if the sample is not representative of the population.
Framework for why sampling methods are essential and how they relate to randomization.

5. Sampling Methods for a Representative Sample
Process
Example
Simple Random Sample (SRS)
Chosen in a way that every individual in the population has an equal chance to be selected for the sample
Ex: Put the names of students in a box, mix the names, and draw 50.
Students mix M+Ms together and randomly select 5

6. Sampling Methods for a Representative Sample
Students organize M+Ms by color and randomly select 1 from each group.

7. Sampling Methods for a Representative Sample
Divide MMs into 3 random groups and select one group as sample

8. Sampling Methods for a Representative Sample
Line up MMs and select every 3rd as sample

9. Sampling Methods for a Representative Sample
Process
Example
Simple Random Sample (SRS)
Chosen in such a way that every individual in the population has an equal chance to be selected for the sample
Ex: Using technology to create a random table of digits, pick 50 KDCA students by ID number.
Stratified Random Sample
Divide the population into strata of individuals that are alike and take an SRS from each strata.
Ex: Divide students by grade and take an SRS from each grade.
Cluster Sample
Divide the population into clusters that are representative of the overall population and sample every individual in a few clusters
Ex: Choosing 5 reading interventions from KDCA and sampling every student.
Systematic Sample
Sample every nth individual in a population
Ex: Sample every 5th person who walks in the door to school.

10. Methods that create Biased Samples

11. Sample Quiz Question

12. Did we accomplish our objective?
Connection to college or career

13. Illuminate Quiz 

14. Before reading discussion (activate prior knowledge)

15. Homework and Independent Practice
Read and respond to Gallup Poll Questions
Khan Academy: Types of Statistical Studies