Sampling techniques

Bivariate data

MYP Standard Mathematics Sampling Techniques Notes

Why We Sample And What Makes A Sample Useful

Definition

Population

The whole group you want information about (for example, all students in your year group).

Definition

Sample

A subset of the population from which data are collected.

We take samples because measuring everyone can be too slow, expensive, or impractical.

The goal is to use the sample to make an inference (a conclusion) about the population.

Whether that inference is reasonable depends on how the sample was chosen.

Definition

Sampling frame

A list (or other complete listing) of all members of the population from which a sample can be selected.

Note

A sample is most convincing when it is representative, meaning it reflects important features of the population (such as age ranges, classes, or product types) in a similar way to the population.

Simple Random Sampling Gives Each Member An Equal Chance

In a simple random sample, every member of the population has an equal chance of being selected, and the selection is genuinely random.

This reduces selection bias because you are not choosing people based on convenience.

Common ways to select a simple random sample include pulling names from a hat (when the group is small) or using a calculator/computer random number generator (RNG).

How To Take A Simple Random Sample (Method)

Define the population clearly.

Create a sampling frame (a complete list).

Number the members from 1 to $N$.

Use an RNG to generate $n$ distinct numbers.

Select the individuals with those numbers.

Common Mistake

"Random" does not mean "haphazard."
Choosing "whoever is nearby" or "the first 20 people I see" is usually convenience sampling, not random sampling.

Duis aute irure dolor in reprehenderit

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Note

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.

Excepteur sint occaecat cupidatat non proident

Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit.

Tip

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Lorem ipsum dolor sit amet, consectetur adipiscing elit.

Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.

Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

Nice try, unfortunately this paywall isn't as easy to bypass as you think. Want to help devleop the site? Join the team at https://revisiondojo.com/join-us. exercitation voluptate cillum ullamco excepteur sint officia do tempor Lorem irure minim Lorem elit id voluptate reprehenderit voluptate laboris in nostrud qui non Lorem nostrud laborum culpa sit occaecat reprehenderit

Definition

Paywall

(on a website) an arrangement whereby access is restricted to users who have paid to subscribe to the site.

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit

Note

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.

Excepteur sint occaecat cupidatat non proident

Tip

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

MYP Standard Mathematics Sampling Techniques Notes

Why We Sample And What Makes A Sample Useful

Simple Random Sampling Gives Each Member An Equal Chance

How To Take A Simple Random Sample (Method)

Systematic Sampling Uses A Random Start And A Fixed Interval

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

Why We Sample And What Makes A Sample Useful

Simple Random Sampling Gives Each Member An Equal Chance

How To Take A Simple Random Sample (Method)

Systematic Sampling Uses A Random Start And A Fixed Interval

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

Number and Algebra Foundations7 subtopics

Coordinate Geometry and Linear Modelling5 subtopics

Functions and Quadratic Relationships4 subtopics

Sets, Logic and Probability4 subtopics

Geometry of Shapes, Surface Area and Volume3 subtopics

Statistical Measures and Data Representation3 subtopics

Right Triangles and Circle Geometry3 subtopics

Sequences, Formulae and Proportional Reasoning3 subtopics

Sampling Methods and Bivariate Data2 subtopics

MYP Standard Mathematics Sampling Techniques Notes

Number and Algebra Foundations7 subtopics

Coordinate Geometry and Linear Modelling5 subtopics

Functions and Quadratic Relationships4 subtopics

Sets, Logic and Probability4 subtopics

Geometry of Shapes, Surface Area and Volume3 subtopics

Statistical Measures and Data Representation3 subtopics

Right Triangles and Circle Geometry3 subtopics

Sequences, Formulae and Proportional Reasoning3 subtopics

Sampling Methods and Bivariate Data2 subtopics

Why We Sample And What Makes A Sample Useful

Simple Random Sampling Gives Each Member An Equal Chance

How To Take A Simple Random Sample (Method)

Systematic Sampling Uses A Random Start And A Fixed Interval

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

Why We Sample And What Makes A Sample Useful

Simple Random Sampling Gives Each Member An Equal Chance

How To Take A Simple Random Sample (Method)

Systematic Sampling Uses A Random Start And A Fixed Interval

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account