Statistical Study Design: Free Course

About this course

Reliable statistical conclusions begin with how observations are collected. This course examines populations, samples, bias, random sampling and the distinction between observation and experiment. Study the complete public source playlist from Khan Academy in English, with all 13 recordings available in the on-site classroom. Lessons retain their original titles and source order, including worked examples, introductions and repeated entries.

Course at a glance

What you’ll learn

• Identify the target population and observed sample.
• Recognize undercoverage and other survey biases.
• Distinguish random sampling from the design of an experiment.
• Assess generalization and causal claims using the study design.

Skills you’ll gain

• Sampling
• Survey bias
• Experimental design
• Causal reasoning

Course Overview

The opening examples identify the population a question concerns and the sample actually observed. Survey coverage and other sources of bias explain why a large dataset can still misrepresent that population. Random-sampling techniques are then considered as deliberate design choices. The course distinguishes observational studies from experiments and uses worked examples to make the difference concrete. Matched-pairs design introduces a way to organize comparisons when observations are related. The final lessons test proposed conclusions: whether a finding can be generalized and whether a causal statement is supported are separate questions. The orbital-speed example and other applications remain in their source positions as practice with study reasoning. Your goal is to explain the relationship between a design choice and the claim it permits, rather than merely attach a study-type label.

How to study the course

• Videos 1–3: this part of the source list includes “Identifying a sample and population” through “Examples of bias in surveys”. Define the question and the observations. Keep a brief working note, revisit an unclear explanation and test one example before moving to another part of the material.
• Videos 4–6: this part of the source list includes “Example of under coverage introducing bias” through “Techniques for random sampling and avoiding bias”. Check the assumptions behind a method. Keep a brief working note, revisit an unclear explanation and test one example before moving to another part of the material.
• Videos 7–9: this part of the source list includes “Types of statistical studies” through “Worked example identifying observational study”. Connect a calculation with a plain-language interpretation. Keep a brief working note, revisit an unclear explanation and test one example before moving to another part of the material.
• Videos 10–13: this part of the source list includes “Impact of mass on orbital speed” through “Can causality be established from this study?”. Describe uncertainty and limits of a conclusion. Keep a brief working note, revisit an unclear explanation and test one example before moving to another part of the material.

Who is this for?

This course suits students, analysts and readers who want to understand the specific statistical methods in the course. It also provides a recorded reference for revisiting a topic after an earlier lesson or study attempt. Choose examples appropriate to your background and allow time to work through the method instead of judging understanding only by how familiar the terminology sounds.

Before you start

Basic arithmetic and familiarity with tables and graphs are helpful. More advanced probability or inference topics assume the prerequisite methods shown in the recordings.

Put the lessons into practice

Draft a fictional survey question and specify who belongs to its target population, how participants would be selected and who might be missed. Then outline an experiment on a different question, including a comparison and a reason for using matched pairs if appropriate. Write one conclusion each design could support and one stronger conclusion it could not justify.

This optional study activity is provided by WikiFree for independent practice. Keep your working notes and use the relevant classroom recording to check a step, definition or interpretation. It is not an instructor-marked assignment.

Certificate / Assessment

Watching the public videos and using WikiFree completion tracking does not award a certificate, academic credit, an examination voucher or instructor assessment. Use your practice output to review what you can explain and repeat independently. The recorded lessons provide study material; completion tracking records your progress through that material.

Frequently asked questions

Provider: Khan Academy. Videos play from the Khan Academy channel on YouTube.