We may be living IN a simulation (according to Elon Musk and many others), but that doesn't mean we don't need to perform simulations ourselves. Today, we're going to talk about good experimental design and how we can create controlled experiments to minimize bias when collecting data. We'll also talk about single and double blind studies, randomized block design, and how placebos work.

In which Craig Benzine tells you how we keep bureaucracy in check. So we've spent the last few episodes telling you all about what bureaucracies are and why they are formed. And throughout we've hinted about this ever-expanding power within the executive branch. So today, we're going to finish our discussion of bureaucracy by looking at methods the other branches of government use to manage this power. From watch-dog organizations to reporting requirements there has been quite a bit of legislation passed aimed at taming the bureaucracy.

Well, it wouldn't be too long after we started developing Ecology that we would try to control the environment. In some ways this was helpful and likely prevented a lot of people from starving. But, there have been a few downsides.

So, how many different kinds of intelligence are there? And what is the G-Factor? Eugenics? Have you ever taken an IQ Test? All of these things play into the fascinating and sometimes icky history of Intelligence Testing. In this episode of Crash Course Psychology, Hank talks us through some of the important aspects of that history... as well as Nazis. Hey, I said some of it was icky.

Chapters:
Introduction: Defining Intelligence
The G-Factor
Psychometrics
Gardner's 8 Intelligences
Measuring Creativity & Divergent Thinking
Emotional Intelligence
Eugenics
Binet & Simon's "Mental Age" Tests
IQ Tests
Intelligence Tests, Eugenics, & Forced Sterilization in the U.S.
Eugenics in Nazi Germany
Review & Credits
Credits

This week, Stan Muller teaches you the basics of copyright in the United States. Copyright law is territorial, so we're going to cover the system we know the most about, and that's the US. Stan will talk about what kind of ideas can be copyrighted, who can get a copyright, and what protections the copyright grants. We'll also talk about the always contentious and seemingly ever-growing term of copyright. Stan will also teach you about the low bar for creativity, which means that original work doesn't have to be all that original, and he'll also touch on the problems with copyright in the modern world.

Stan Muller teaches you a few things about copyright enforcement and talks about the exceptions to copyright enforcement. While there are several, the one you've probably heard of is Fair Use, and it's a pretty tricky one. We'll try to explain it and teach you just why fair use is so loosey-goosey.

When someone says they’re “studying business” or they “work in business,” they could mean so many different things. They could be in marketing, sales, finance or human resources. So much goes into keeping a company running smoothly.

Today we’re going to talk about data relationships and what we can learn from them. We’ll focus on correlation, which is a measure of how two variables move together, and we’ll also introduce some useful statistical terms you’ve probably heard of like regression coefficient, correlation coefficient (r), and r^2. But first, we’ll need to introduce a useful way to represent bivariate continuous data - the scatter plot. The scatter plot has been called “the most useful invention in the history of statistical graphics” but that doesn’t necessarily mean it can tell us everything. Just because two data sets move together doesn’t necessarily mean one CAUSES the other. This gives us one of the most important tenets of statistics: correlation does not imply causation.

In which Mike teaches you about the creation of the universe, with sex. This week we're talking about creations stories from Egypt, West Africa, Greece, China, and Persia that have a lot in common with human sexual reproduction. And also some castration and puking, to boot. We've got your cosmic eggs, right here!

In our journey through the history of the entire universe, we have reached the present. Before we continue moving forward in our timeline, John has some questions for Katie that he's been holding back.

Mike Rugnetta continues to teach you about Tricksters in myth, and this time we're headed to the Americas. Coyote and Raven appear in stories from many Native American groups, and more often than not, they're tricky. They're also often kind of, well, nasty. Not to get too judgy. But we do a lot of talking about poop in this episode. I'm just saying. We also talk about Tricksters as creators, as Coyote creates constellations, and Raven creates some rivers.

In which Jacob Clifford and Adriene Hill introduce you to Crash Course Economics! CC Econ is a new course from the Crash Course team. We look forward to teaching you all about the so-called dismal science.

Welcome to Crash Course Office Hours! Is the heart an organ? How does the nervous system work? In this livestream, Hank Green and Brandon Jackson answer the questions you submitted and talk about the best ways to study anatomy & physiology.

Chapters:
Introduction
Is the heart a muscle or an organ?
How are skin cells organized through the layers of the skin?
Neurotransmitters, action potential, gated channels, and the process of muscle contraction
What's the best way to remember bone landmarks?
How to read an ECG
Tips for studying A&P #1 - learning the root words
Tips for studying A&P #2 - how to use flashcards
Tips for studying A&P #3 - learning by teaching
What happens when a muscle cramps?
Tricks for remembering the veins and arteries
Outro

Welcome to Crash Course Office Hours! Alizé Carrère and April Luginbuhl Mather answer your questions on human and physical geography, including how rocks form, how melting glaciers impact water resources, and what even is geography?

Chapters:
Introduction
What is geography?
Place, space, and location
Site, situation and scale
How do different types of rock form?
Reducing the impacts of earthquakes and volcanoes
How is a meander formed?
Origin and formation of fjords
How can mountain ecosystems be restore from the impact of development and tourism?
Impact of melting Himalayan glaciers on water resources
What is posthumanism?
Who are significant geographers?
Different types of boundaries
What are the markers of development?
What is in a geography course?
Tips for studying geography
Why do we personally find geography interesting?
How to talk to students about the politics of maps
Displacement of people due to war, natural disasters, and changing coastlines
How do metamorphic rocks form?
Careers for people who study geography
Outro

Welcome to Crash Course World History Office Hours! John Green and Cathy Keller answer your questions on the Russian Revolution, discuss the origin of nation states, and talk about the best way to approach studying history.

Chapters:
Introduction
Causes and effects of the Russian revolution
Who was Genghis Khan and how was he able to get so much territory?
How did the Cold War start?
Kwame Nkrumah and Ghana in African decolonization and the Cold War
The differences between the Aztecs, Incas, and Mayans
Ataturk and the origin of nation-states
What's the best way to look back on history?
Tips for studying World History
Why didn't the silk road stretch all the way across Europe?
Favorite books on history
Outro

Today on Crash Course Mythology we’re starting in on creation stories. This week, we’ll focus on the creation of the universe out of nothing, or Ex Nihlio creation. Basically, a god decides to make a universe out of nothing. We’ll look at the Genesis story (which has nothing to do with Peter Gabriel or Phil Collins), a Mayan creation tale, a Kono story of the beginning, and we’ll even look at the Big Bang.

Today's Crash Course Chemistry takes a historical perspective on the creation of the science, which didn't really exist until a super-smart, super-wealthy Frenchman put the puzzle pieces together - Hank tells the story of how we went from alchemists to chemists, who understood the law of conservation of mass as proposed by a decapitated aristocrat, and explains how we came to have a greater understanding of how chemical compounds work and eventually a complete understanding of what atoms and molecules are.

Chapters:
Alchemists to Chemists
Law of Conservation of Mass
Decapitated Aristocrat
Chemical Compounds
Atoms and Molecules :1

We’ve talked about deviance more broadly, but today we’re focusing on crime, specifically in the US. We’ll start with legal definitions of crime and use FBI data to get an idea of the amount and kinds of crime committed in the US. We’ll also use that date to paint a demographic picture of who gets arrested, and explain why that’s not necessarily a full look of who commits crime. We’ll also discuss society’s response to crime in the criminal justice system, and how that response has resulted in mass incarceration.

Insects can communicate with each other about all kinds of things, but instead of using words, they use… you guessed it! Organic Chemistry! Insects can send signals to each other by secreting compounds, and one such compound used by termites contains the functional group we’re going to learn all about in this episode: enones! In this episode of Crash Course Organic Chemistry, we’ll learn about crossed aldol reactions, the formation of kinetic and thermodynamic enolates, hard and soft nucleophiles, conjugate addition, and of course, enones!

In which John Green teaches you about the Crusades embarked upon by European Christians in the 12th and 13th centuries. Our traditional perception of the Crusades as European Colonization thinly veiled in religion isn't quite right. John covers the First through the Fourth Crusades, telling you which were successful, which were well-intentioned yet ultimately destructive, and which were just plain crazy. Before you ask, no, he doesn't cover the Children's Crusade, in which children were provoked to gather for a Crusade, and then promptly sold into slavery by the organizers of said Crusade. While this story is charming, it turns out to be complete and utter hooey.

Chapters:
Introduction: The Crusades
What Prompted the Crusades?
The First Crusade
An Open Letter to Animal Crackers
What Motivated the Crusaders?
The Third Crusade
The Fourth Crusade
What Did The Crusades Accomplish?
Credits