My four-year old often likes to make jokes that show no understanding of cause and effect. One might go something like this: Why did the cow fall down? Because it hit the ground!
But all joking aside, after spending at least five years teaching cause and effect essays, I've found that my students often have a weak understanding of what the difference between a cause and an effect is. Since I just read a chapter for the statistics class I'm taking on the matter, I thought I'd share how teachers can better help students understand the difference.
After lecturing on how the students will organize their cause or effects essay, I'd ask them how they can tell the difference between causes and effects. They'd usually then define it with synonyms. "An effect is the result," they might say or, "a cause is a reason something happens." Of course, if I then followed up by asking about the difference between results and reasons, they'd run out of synonyms. The first point I'd make regarding the relationship between the two is what is called time-order, that is that causes always come before effects. This has to be the case unless time travel is possible, in which case you could create a paradox by going back in time and killing your own grandfather (a joke which has consistently gone over every single one of my students' heads).
It sounds simple enough, but I let them know that it can sometimes be difficult to tell which came first. We then have a discussion about which came first, the chicken or the egg, that goes pretty much like below:
I also have to warn them though that just because something precedes another doesn't mean that a causal relationship exists. I then would give an absurd example, something like how I had oatmeal for breakfast then got in a car accident. Therefore, the oatmeal caused my car accident. They'd all laugh, then I'd explain that this is an example of what is called a post hoc ergo propter hoc error, which is a fancy Latin phrase that basically means that just because time-order is established, doesn't mean the two have anything to do with each other.
This is obviously an absurd example, but again people often make these kinds of mistakes. For instance, every year I hear about people who get flu shots and then a day later they get sick. They come to the conclusion that the shot caused them to get the flu, but couldn't a completely different factor be the cause? After all, you become infected with a disease a few days before you develop any symptoms, and you generally get a flu shot at a time when you're at a high risk of getting infected. Now, I'm no medical doctor, so I really don't know the answer. I only bring it up to students to teach them about nonspuriousness, which means that in order to prove causation, you need to consider and disprove any additional factors.
Lastly, I give them another example of a coin toss.
The first toss is heads, then tails, then heads, then tails, tails, tails, tails, tails, tails. So what is going to come next? Heads or tails? After all, it's been a while since heads came up. It's due, isn't it? But on the other hand, tails is on a run. It's had six in a row! I let them think about it for a second, then ask them to raise their hands to decide which they believe is going to come next. A few say heads, and a few other tails. Of course, they're all wrong.
The odds that the next toss will be heads is 50% and the odds it will be tails is 50%. What comes before has absolutely no effect whatsoever on what is going to come after. The problem is that our brains are designed to look for patterns, and sometimes we find them where no patterns exist. This particular example is known as the Gambler's Dilemma (so it's a good thing all of my students are good Muslims, so they don't gamble). This demonstrates the importance of covariance, which is that there actually has to be a statistical association between the two variables being considered.
I also give my students a simple linguistic method to determine cause and effect, which is to form a sentence with them using the word "because." So, if for instance they didn't study for their test and got an F, they could say "Because I didn't study for the test, I got an F." The cause always comes immediately after "because." If they reverse it (Because I got an F, I didn't study for the test), then the sentence takes on a very different meaning.
But all joking aside, after spending at least five years teaching cause and effect essays, I've found that my students often have a weak understanding of what the difference between a cause and an effect is. Since I just read a chapter for the statistics class I'm taking on the matter, I thought I'd share how teachers can better help students understand the difference.
After lecturing on how the students will organize their cause or effects essay, I'd ask them how they can tell the difference between causes and effects. They'd usually then define it with synonyms. "An effect is the result," they might say or, "a cause is a reason something happens." Of course, if I then followed up by asking about the difference between results and reasons, they'd run out of synonyms. The first point I'd make regarding the relationship between the two is what is called time-order, that is that causes always come before effects. This has to be the case unless time travel is possible, in which case you could create a paradox by going back in time and killing your own grandfather (a joke which has consistently gone over every single one of my students' heads).
It sounds simple enough, but I let them know that it can sometimes be difficult to tell which came first. We then have a discussion about which came first, the chicken or the egg, that goes pretty much like below:
A Chicken-Egg Situation
Obviously, my students aren't going to be writing about poultry, so I point out that there are actually lots of situations where time order can be difficult to determine. For instance, do violent video games make players become more violent? Most of my students (who are female by the way, so they think of the examples of their younger brothers) immediately agree with this until I point the equally plausible idea that people who are already violent are more attracted to violent video games.
I also have to warn them though that just because something precedes another doesn't mean that a causal relationship exists. I then would give an absurd example, something like how I had oatmeal for breakfast then got in a car accident. Therefore, the oatmeal caused my car accident. They'd all laugh, then I'd explain that this is an example of what is called a post hoc ergo propter hoc error, which is a fancy Latin phrase that basically means that just because time-order is established, doesn't mean the two have anything to do with each other.
This is obviously an absurd example, but again people often make these kinds of mistakes. For instance, every year I hear about people who get flu shots and then a day later they get sick. They come to the conclusion that the shot caused them to get the flu, but couldn't a completely different factor be the cause? After all, you become infected with a disease a few days before you develop any symptoms, and you generally get a flu shot at a time when you're at a high risk of getting infected. Now, I'm no medical doctor, so I really don't know the answer. I only bring it up to students to teach them about nonspuriousness, which means that in order to prove causation, you need to consider and disprove any additional factors.
Lastly, I give them another example of a coin toss.
Value of a 50 Qatari dirham coin = roughly $0.14
The first toss is heads, then tails, then heads, then tails, tails, tails, tails, tails, tails. So what is going to come next? Heads or tails? After all, it's been a while since heads came up. It's due, isn't it? But on the other hand, tails is on a run. It's had six in a row! I let them think about it for a second, then ask them to raise their hands to decide which they believe is going to come next. A few say heads, and a few other tails. Of course, they're all wrong.
The odds that the next toss will be heads is 50% and the odds it will be tails is 50%. What comes before has absolutely no effect whatsoever on what is going to come after. The problem is that our brains are designed to look for patterns, and sometimes we find them where no patterns exist. This particular example is known as the Gambler's Dilemma (so it's a good thing all of my students are good Muslims, so they don't gamble). This demonstrates the importance of covariance, which is that there actually has to be a statistical association between the two variables being considered.
I also give my students a simple linguistic method to determine cause and effect, which is to form a sentence with them using the word "because." So, if for instance they didn't study for their test and got an F, they could say "Because I didn't study for the test, I got an F." The cause always comes immediately after "because." If they reverse it (Because I got an F, I didn't study for the test), then the sentence takes on a very different meaning.
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