Too many conclusions can be attached to a single piece of data
Using sound logic is vital for advanced communication. It can help to understand and answer questions clearly in meetings, conversation or English tests. This lesson is about cause and effect, compared with correlation.
We will discuss how to build an argument using cause and effect, and how it can be confused with correlation.
Establishing the parts of an argument might be important. An argument requires these parts:
- claims;
- reasoning and evidence; and
- a conclusion.
A man points to a chart that shows how temperatures around the world have been rising over the past two centuries. The chart shows that at the same time, the number of people wearing traditional Japanese kimonos has been decreasing. Thus, he argues, the number of people wearing kimonos effects the global temperature, and the answer to global warming is to make kimonos popular again.
We can agree that he is completely incorrect, but why is he incorrect?
This logical fallacy is confusing coexisting data with causative data.
Coexisting data is when two things happen at the same time, or when two things happen together
Causative data is when one point actually causes the next point.
Just because two things happen together, that doesn't mean that one causes the other.
Other points (if the student is interested):
- Did the peak number of kimonos correspond with the lowest global temperature?
- Was the falling number inversely correlated with the rising temperatures?
- Have any experts stated this opinion?
- Can a single kimono lower the temperature of a small area? (Can we perform a small test?)
First we will talk about correlation and causation. What do these words mean? Try to think of some examples.
Correlation
Here are some commonly used patterns:
- A and B are correlated.
- There is a (weak/strong) correlation between A and B.
Causation
When discussing causation, it's common to use so, because (of), or therefore.
Be careful not to confuse cause and because.
- Being out in the sun can cause a sunburn because of dangerous UV rays.
- The cost of fuel dropped; therefore, airplane tickets got cheaper. This is a case of overhead costs dropping, which usually causes a drop in price for the end user.
Examples of correlation
- simple: I am gesturing a thumbs up with one hand, and I am pointing up with the other hand.
- complex: crime rates in New York dropped after Rudy Giuliani became mayor.
There are some good spurious correlations on this page.
Example of causation
- I am bringing my umbrella because the weather forecast says it will rain this afternoon.
- The weather report said it will rain, therefore I'm bringing my umbrella.
This is causative because it's my choice.
* In case your student isn't sure about the difference between cause and because, you can discuss it.
- Cause is used to refer to the underlying factor or root of a problem or situation.
- Because is used to explain why something is the case.
Extra teacher's notes
The verbs get or have can be used for one person causing another person to do an action.
- The president had all his staff come to a meeting.
- Martha is having her friend help her with her some work.
- A husband is getting his wife to pick up their son from school.
Read and discuss these situations in terms of being a correlation or a causation. What information would you need to make the causation clear?
- I want my favorite baseball team to win, so I'm wearing red underpants! Last time I wore them, my team won.
- In Canada, immigration from Ontario to Alberta increased. Soon after, the number of people receiving welfare in Alberta increased. Therefore, the increased immigration caused the increased welfare rolls.
Now, choose a question below and make a strong case for causation:
- Does expensive equipment improve your performance in a hobby?
- If the economy goes down, does that mean sales of electronics will also decrease?
- Does living in a big city affect your stress level?