MA.912.DP.5.2

Explain how random sampling produces data that is representative of a population.
General Information
Subject Area: Mathematics (B.E.S.T.)
Grade: 912
Strand: Data Analysis and Probability
Status: State Board Approved

Benchmark Instructional Guide

Connecting Benchmarks/Horizontal Alignment

 

Terms from the K-12 Glossary

  • Data 
  • Population (in data analysis) 
  • Random sampling 
  • Statistical question

Vertical Alignment

Previous Benchmarks

Next Benchmarks

Purpose and Instructional Strategies

In grades 6 and 7, students examined formulating statistical questions to formulate data and used proportional relationships to make predictions about a population. In Mathematics for College Statistics, students explore how they can extend this idea to random sampling in order to produce data that is representative of the population. 
  • Instruction references MA.912.DP.5.1 to reinforce that often times a population is too large to collect data from each individual; a sample is selected as a subset of the population. In order to produce a sample that has similar demographics to the population, a random sample should be selected. 
  • Instruction explains how convenience samples and voluntary response samples lead to biased samples that most likely do not represent the entire population. 
    • For example, if a college professor talks to the first 50 students entering the on campus library on a Monday morning, this would be a biased convenience sample that would not share the characteristics of all students in the population. Students who only take evening classes or who only take online classes are most likely not represented by this sample. 
  • Students should understand that by randomly selecting a sample from the entire population everyone/everything in the population has an equal chance of being selected. This lack of bias allows for a variety of people/objects to be selected so that various characteristics are present in the sample. Therefore, the makeup of the sample is similar to that of the population, and we can say the sample is representative. 
  • Instruction includes using technology and/or applets to randomly select a sample from a population to see how the sample has similar characteristics when compared to the population. 
  • Avoid measurement bias by having an appropriate statistical question. When asking a question to collect data that is representative of the population, the question should be clear, concise and free of any language that may bias the response of any participants.

Common Misconceptions or Errors

  • Students may have initially misconceptions regarding how a random sample does not lead to a biased sample. They may incorrectly assume that randomly selecting from the population will inadvertently leave out certain groups. Using simulations and applets can help with this misconception.

Instructional Tasks

Instructional Task 1 (MTR.4.1, MTR.7.1
  • A manager for an office supply store has a large shipment of 2,000 calculators being delivered today. If more than 2% of the calculators are defective, he will not accept the shipment and will have to send them all back. Due to time constraints he cannot test all 2,000 calculators to make sure enough of them work; he can only test 100. The manager decides that he will take a sample of 100 calculators and test them to estimate the percentage in the shipment that are defective. 
    • Part A. Why would checking the first 100 calculators most likely not produce data that is representative of the population? Explain. 
    • Part B. What would be the best way to get sample that produces data that is representative of the population? Elaborate on how the manager could get this type of sample. 
    • Part C. Suppose the manager takes a sample using the method that you wrote about in Part B, and he finds that 6 out of 100 calculators are defective and do not work. What should the manager do? Can he feel confident even though he has only sampled 100 calculators? Explain your reasoning

Instructional Items

Instructional Item 1 
  • A teacher wants a representative sample of students at her school to get feedback on this year’s homecoming theme. Which sample would most likely produce data that is representative of the population? 
    • a. She should poll the 30 students in her homeroom class.
    • b. She should survey 100 students waiting for the buses after school. 
    • c. She should randomly sample 50 students from the entire population of the school. 
    • d. She should talk to each student who eats lunch on campus this upcoming Friday.

*The strategies, tasks and items included in the B1G-M are examples and should not be considered comprehensive.

Related Courses

This benchmark is part of these courses.
1210300: Probability and Statistics Honors (Specifically in versions: 2014 - 2015, 2015 - 2019, 2019 - 2022, 2022 - 2024, 2024 and beyond (current))
1210305: Mathematics for College Statistics (Specifically in versions: 2022 - 2024, 2024 and beyond (current))
1209315: Mathematics for ACT and SAT (Specifically in versions: 2022 - 2024, 2024 and beyond (current))

Related Access Points

Alternate version of this benchmark for students with significant cognitive disabilities.

Related Resources

Vetted resources educators can use to teach the concepts and skills in this benchmark.

Lesson Plans

Show Me the Money:

Students will create a statistical question and collect and analyze data using relative frequency tables. They will present their argument in hopes of earning a cash prize for their philanthropy. An iterative process of critique and refinement will take place. A student packet is included that guides all parts of the lesson.

Type: Lesson Plan

Is It a Guess or Statistics?:

This lesson teaches random sampling which leads to making inferences about a larger group or population. Students will determine the best measure of center to use for a data set. Students will collect data, select a data display and then analyze the data.

Type: Lesson Plan

Advantages and Disadvantages of Dot Plots, Histograms, and Box Plots:

Students will compare the advantages and disadvantages of dot plots, histograms, and box plots. During this lesson, students will review the statistical process and learn the characteristics of a statistical question; whether it be numerical or categorical. Students will apply the information learned in a project that involves real-world issues and make an analysis based on the data collected.

Type: Lesson Plan

Inferences:

This lesson shows students how to conduct a survey and display their results. The lesson takes the students through:

  1. What is a statistical question?
  2. General population versus sample population.
  3. What is a hypothesis?
  4. What is a survey?
  5. How to make inferences.

Type: Lesson Plan

5K and No More - Producing Data:

Can your school use $5000? What school doesn't?! Well, the money is available, but the student body must decide how the money will be spent!

5K and No More - Producing Data will enable students to fantasize about what they would do to improve their school if allowed to answer the question, "How would $5000 best be spent at your school?" The activity begins with students distinguishing the differences between a sample survey, an experiment, and an observational study through a pre-activity. After this, the students are given five (5) scenarios in which they must discuss the pros and cons of each. In life we want things to be fair, so students must constantly think about bias. The company in this MEA desires the most efficient and effective way to collect information from the students without having to talk to everyone ... who has that kind of time!

Now, just when the students have found the most efficient and effective way to get students to share their thoughts on where the money should go, more information is revealed about the High School. How do we account for the brains and the brawn, the perfect attendee and the most missed days, or for the goth or skater?

Your Savvy Statisticians in the making will figure it out and tell you ALL about it.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought processes. MEAs follow a problem-based, student-centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEAs visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Generating Multiple Samples to Gauge Variation:

Students explore variation in random samples and use random samples to make generalizations about the population.

Type: Lesson Plan

Perspectives Video: Experts

Birdsong Series: Statistical Analysis of Birdsong:

<p>Wei&nbsp;Wu discusses his statistical contributions to the Birdsong project which help to quantify&nbsp;the differences in the changes of the zebra finch's song.</p>

Type: Perspectives Video: Expert

Birdsong Series: STEM Team Collaboration :

<p>Researchers Frank Johnson, Richard Bertram,&nbsp;Wei&nbsp;Wu, and Rick&nbsp;Hyson&nbsp;explore the necessity of scientific and mathematical collaboration in modern neuroscience, as it relates to their NSF research on birdsong.</p>

Type: Perspectives Video: Expert

fMRI, Phantom Limb PainĀ and Statistical Noise:

<p>Jens Foell&nbsp;discusses how statistical noise reduction is used in fMRI&nbsp;brain imaging to be able to determine which specifics parts of the brain are related to certain activities and how this relates to patients that suffer from phantom limb pain.</p>

Type: Perspectives Video: Expert

Statistical Inferences and Confidence Intervals :

<p>Florida State University Counseling Psychologist&nbsp;discusses how he uses confidence intervals to make inferences on college students' experiences on campus based on a sample of students.</p>

Type: Perspectives Video: Expert

MicroGravity Sensors & Statistics:

Statistical analysis played an essential role in using microgravity sensors to determine location of caves in Wakulla County.

Download the CPALMS Perspectives video student note taking guide.

Type: Perspectives Video: Expert

Perspectives Video: Professional/Enthusiasts

Fishery Independent vs Dependent Sampling Methods for Fishery Management:

<p>NOAA&nbsp;Scientist Doug Devries discusses the differences between fishery independent surveys and fishery independent surveys. &nbsp;Discussion&nbsp;includes trap sampling as well as camera sampling. Using&nbsp;graphs to show changes in population of red snapper.</p>

Type: Perspectives Video: Professional/Enthusiast

Camera versus Trap Sampling: Improving how NOAA Samples Fish :

<p>Underwater sampling with cameras has made fishery management more accurate for NOAA&nbsp;scientists.</p>

Type: Perspectives Video: Professional/Enthusiast

Linear Regression for Analysis of Sea Anemone Data:

<p>Will Ryan describes how linear regression models contribute towards his research on sea anemones.</p>

Type: Perspectives Video: Professional/Enthusiast

Sampling Strategies for Ecology Research in the Intertidal Zone:

<p>Will Ryan describes methods for collecting multiple random samples of anemones in coastal marine environments.</p>

Type: Perspectives Video: Professional/Enthusiast

Making Inferences about Wetland Population Sizes:

<p>This ecologist from the Coastal Plains Institute discusses sampling techniques that are used to gather data to make statistical inferences about amphibian populations in the wetlands of the Apalachicola National Forest.</p>

Type: Perspectives Video: Professional/Enthusiast

How to Build a Research Study on Education:

<p>This researcher explains common methods behind randomized studies in the social sciences, specifically in education.</p>

Type: Perspectives Video: Professional/Enthusiast

Statistical Analysis of a Randomized Study:

<p>This education researcher uses measures of center and measures of variability for numerical data from random samples to draw informal comparative inferences about two populations.</p>

Type: Perspectives Video: Professional/Enthusiast

Population Sampling and Beekeeping:

<p>This buzzworthy video features statistics, sampling, and how scientists make inferences about populations.</p>

Type: Perspectives Video: Professional/Enthusiast

Problem-Solving Tasks

Why Randomize?:

This task requires students to estimate the mean (average) area of the population of 100 rectangles using the average area of a sample of 5 rectangles. Students are asked to make one estimate using a judgement sample and another using a random sample of the population. Finally, students are asked to consider bias in sampling methods.

Type: Problem-Solving Task

Strict Parents:

This task challenges students to describe parameter of interest for the given context, and design a sample survey.

Type: Problem-Solving Task

Musical Preferences:

This problem solving task asks students to make deductions about the kind of music students enjoy by examining data in a two-way table.

Type: Problem-Solving Task

School Advisory Panel:

Students are asked to choose the best sampling method for choosing the new School Advisory Panel.

Type: Problem-Solving Task

Words and Music II:

The purpose of this task is to assess (1) ability to distinguish between an observational study and an experiment and (2) understanding of the role of random assignment to experimental groups in an experiment.

Type: Problem-Solving Task

Estimating the Mean State Area:

The task is designed to show that random samples produce distributions of sample means that center at the population mean, and that the variation in the sample means will decrease noticeably as the sample size increases.

Type: Problem-Solving Task

Text Resources

Sample Size Calculation:

This informational text resource is intended to support reading in the content area. This article describes the important process used when setting up trials for statistical investigation. The article explains each parameter that is needed to calculate the sample size, then provides examples and illustrates the process. This article will enhance an upper level math course's study of statistics after significance levels and basic inferential statistics concepts have been taught.

Type: Text Resource

How to Win at Rock-Paper-Scissors:

This informational text resource is intended to support reading in the content area. This article describes a new study about the game rock-paper-scissors. The study reveals that people do not play randomly; there are patterns and hidden psychology players frequently use. Understanding these potential moves can help a player increase their winning edge. As part of interpreting the results of the study, the article references the Nash equilibrium and the "win-stay lose-shift" strategy.

Type: Text Resource

STEM Lessons - Model Eliciting Activity

5K and No More - Producing Data:

Can your school use $5000? What school doesn't?! Well, the money is available, but the student body must decide how the money will be spent!

5K and No More - Producing Data will enable students to fantasize about what they would do to improve their school if allowed to answer the question, "How would $5000 best be spent at your school?" The activity begins with students distinguishing the differences between a sample survey, an experiment, and an observational study through a pre-activity. After this, the students are given five (5) scenarios in which they must discuss the pros and cons of each. In life we want things to be fair, so students must constantly think about bias. The company in this MEA desires the most efficient and effective way to collect information from the students without having to talk to everyone ... who has that kind of time!

Now, just when the students have found the most efficient and effective way to get students to share their thoughts on where the money should go, more information is revealed about the High School. How do we account for the brains and the brawn, the perfect attendee and the most missed days, or for the goth or skater?

Your Savvy Statisticians in the making will figure it out and tell you ALL about it.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought processes. MEAs follow a problem-based, student-centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEAs visit: https://www.cpalms.org/cpalms/mea.aspx

Student Resources

Vetted resources students can use to learn the concepts and skills in this benchmark.

Perspectives Video: Expert

MicroGravity Sensors & Statistics:

Statistical analysis played an essential role in using microgravity sensors to determine location of caves in Wakulla County.

Download the CPALMS Perspectives video student note taking guide.

Type: Perspectives Video: Expert

Perspectives Video: Professional/Enthusiast

Population Sampling and Beekeeping:

<p>This buzzworthy video features statistics, sampling, and how scientists make inferences about populations.</p>

Type: Perspectives Video: Professional/Enthusiast

Problem-Solving Tasks

Musical Preferences:

This problem solving task asks students to make deductions about the kind of music students enjoy by examining data in a two-way table.

Type: Problem-Solving Task

School Advisory Panel:

Students are asked to choose the best sampling method for choosing the new School Advisory Panel.

Type: Problem-Solving Task

Words and Music II:

The purpose of this task is to assess (1) ability to distinguish between an observational study and an experiment and (2) understanding of the role of random assignment to experimental groups in an experiment.

Type: Problem-Solving Task

Parent Resources

Vetted resources caregivers can use to help students learn the concepts and skills in this benchmark.

Perspectives Video: Professional/Enthusiast

Population Sampling and Beekeeping:

<p>This buzzworthy video features statistics, sampling, and how scientists make inferences about populations.</p>

Type: Perspectives Video: Professional/Enthusiast

Problem-Solving Tasks

Musical Preferences:

This problem solving task asks students to make deductions about the kind of music students enjoy by examining data in a two-way table.

Type: Problem-Solving Task

School Advisory Panel:

Students are asked to choose the best sampling method for choosing the new School Advisory Panel.

Type: Problem-Solving Task

Words and Music II:

The purpose of this task is to assess (1) ability to distinguish between an observational study and an experiment and (2) understanding of the role of random assignment to experimental groups in an experiment.

Type: Problem-Solving Task