1. Good vs. Bad PPTs

2. Good “sunk cost fallacy”
Uses the name of the bias that is shorter and easier to say and understand.
“sunk cost fallacy”

3. Bad “irrational escalation of commitment”
Uses the name of the bias that is longer and more confusing.
“irrational escalation of commitment”

4. Good
Explains it in your own words. Gives an original source. (Not just Wikipedia, but the original source.)
We look at how much time, effort, and money we spent on something in the past when we decide what to do in the future, instead of looking at whether something is a good idea to continue.1

5. Bad
Difficult to understand. Copies Wikipedia. Not your own words, no source is given. This is plagiarism. Read about plagiarism here (
The phenomenon where people justify increased investment in a decision, based on the cumulative prior investment, despite new evidence suggesting that the decision was probably wrong. Also known as the sunk cost fallacy.

6. Good
No distracting transitions or animations. Few (or no) animations. Only small and simple animations.

7. Bad
Ugly and distracting transition and animations. Animations do not help understanding. Animations waste time. Too many animations.

8. Good
Image is good quality. Picture is not stretched. Text is readable. Image has a source.
If the monkey thinks “I should continue up this tree because I’m already halfway,” instead of going to the better fruit, he will make the sunk cost fallacy. It is better to stop going the wrong way, not continue. 2

9. Bad Here’s an example of the sunk cost fallacy.
Image is low quality. And it is stretched. And there is no source. And the text is hard to read because it is on top of the picture.
Here’s an example of the sunk cost fallacy.

10. Bad Here’s an example of the sunk cost fallacy.
Image is low quality. And it is stretched. And there is no source. And the text is hard to read because it is too close to the image.
Here’s an example of the sunk cost fallacy.

11. Good
Example is easy to understand. Students can relate to it. Not too much text on one slide.
For example, you pay 10,000 won to see a movie. After 1 hour, you hate the movie. You decide to keep watching anyway because you paid to see it. This is the sunk cost fallacy. The money is already gone, so staying longer just means you are wasting more time.

12. Bad
Example is difficult to understand, students can’t relate. Too much text. Copies Wikipedia. Not your own words, no source is given. This is plagiarism. Read about plagiarism here (
For example, the Vietnam War in the US. Escalation of commitment can many times cause behavior change by means of locking into resources. One of the first examples of escalation of commitment was described by George Ball, who wrote to President Lyndon Johnson to explain to him the predictions of the war outcome: “The decision you face now is crucial. Once large numbers of U.S. troops are committed to direct combat, they will begin to take heavy casualties in a war they are ill equipped to fight in a noncooperative if not downright hostile countryside. Once we suffer large casualties, we will have started a well-nigh irreversible process. Our involvement will be so great that we cannot—without national humiliation—stop short of achieving our complete objectives. Of the two possibilities, I think humiliation would be more likely than the achievement of our objectives—even after we have paid terrible costs.” The president decided to continue this war for no good reason, only because so many people had already died. Instead of thinking “let’s stop before anyone else dies” he thought “we should keep fighting because, otherwise, the people who already died will have died for nothing.” In reality, the dead people were already dead, and killing more people did not help anything.

13. Bad
Example is difficult to understand, students can’t relate. Not enough explanation. Copies Wikipedia. Not your own words, no source is given. This is plagiarism. Read about plagiarism here (
Denver International Airport's baggage handling system that was 2 years and $2 billion over budget.

14. Good
Text is easy to read.
For example, you start to read a book. After 200 pages, you hate it. However, you decide that you should finish it because you already spent so much time reading it. The time you spent is gone. Wasting more time on a book you hate will not give you any benefit.

15. Bad FoR eXaMpLe, BlaH bLAh BlAh. FOR EXAMPLE, BLAH BLAH BLAH.
Text is hard to read because of the size, style, font, color, or background.
For example, blah blah blah.
FoR eXaMpLe, BlaH bLAh BlAh.
FOR EXAMPLE, BLAH BLAH BLAH.

16. Good
Good sources. Shows where the information came from exactly. Includes the title, authors’ names, and a link. Gives sources of all information and images.
1 The sunk cost and Concorde effects: Are humans less rational than lower animals? by Hal R. Arkes and Peter Ayton steffect.pdf 2 Image from cost-feeling

17. Bad
Just a link, no author or title information. No number (which information is this?) Used Wikipedia (Wikipedia is not an original source.) No sources for images.