In this video I explain the difference between an algorithm and a heuristic and provide an example demonstrating why we tend to use heuristics when solving problems. While algorithms provide step-by-step procedures that can guarantee solutions, heuristics are faster and provide shortcuts for getting to solutions, though this has the potential to cause errors. In the next few videos we’ll see examples of heuristics that we tend to use and the potential decision-making errors that they can cause.
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Video Transcript:
Hi, I’m Michael Corayer and this is Psych Exam Review. In this video I want to explain the difference between an algorithm and a heuristic and then provide an example that will hopefully help you to see why it is that we tend to use heuristic.
First, what is an algorithm? Well an algorithm is a step by step procedure for solving a problem. The downside of an algorithm is that it tends to be slow because we have to follow each step. We have to move through the process but on the positive side an algorithm guarantees that we’ll get to the solution. If we can follow all the steps, then we will find the solution to the problem. So an algorithm is guaranteed to work but it’s slow.
What’s a heuristic? Well, a heuristic is sort of a mental shortcut. It’s not a step-by-step procedure and so the downside of a heuristic is, because it’s not a step-by-step procedure it doesn’t guarantee that we’ll actually get to the solution. It might not work so a heuristic is not guaranteed.
We don’t know if it will get us to the correct solution but it’s faster, right? Because it’s a shortcut it skips a lot of the steps and says well these probably aren’t going to get to the solution so I’m just going to skip them. Now it could be the case that those steps would have gotten to the solution or would have gotten to a better solution but the heuristic says I mostly am concerned with getting a quick answer rather than the always correct answer.
Ok, so let’s look at an example of a sort of everyday problem that you might experience and how you would solve it using an algorithm versus using a heuristic. So let’s imagine that I’m in my apartment and I want to go somewhere and so of course I need to take my keys with me and I can’t find them. They’re not on my desk where I usually put them and so I have this problem of how do I find my keys.
Well I know that they’re inside the apartment because I’m inside the apartment and I must have unlocked the door to get in. So one thing that I could do is I could follow an algorithm for solving this problem. I could say okay if the keys are definitely in the apartment somewhere then a step-by-step procedure for finding them will be to start in one corner of the apartment and to slowly look in every single location expanding out from that corner of the apartment until I’ve searched every square inch of the apartment and if I do that it is guaranteed that I will find my keys because they must be in the apartment somewhere.
That approach, that step-by-step procedure will guarantee that I find them but as you can already see it’s going to be slow, right? Because I’m not allowed to skip ahead I have to start in one corner and progress through the entire apartment. Now that’s probably not how you look for your keys if you can’t find them. What do you do instead?
You use a heuristic. You use a shortcut. You say “there’s probably a lot of places that I can just not look in because my keys probably aren’t there.” Now I don’t know that for sure because I don’t know where my keys are but a heuristic that I might use in this approach to solving this problem would be to say “why don’t I look the last place that I remember having them” or maybe I should start by looking in the door, maybe I’ve left them in the door when I unlocked it, right?
Now this doesn’t guarantee that my keys are going to be there but there’s a higher likelihood and it’s going to be faster if I look in the two or three places that my keys are usually found then. I’m probably going to find them. It’s not guaranteed; I might not find my keys in those two or three locations. I might say “okay maybe they’re in the pocket of the pants that I was wearing yesterday or maybe they’re in the door or maybe I set them down on the kitchen table instead of in my bedroom” right?
So what a heuristic does, it says check those places first, take a shortcut. Don’t start looking under the couch, I mean the odds of them being under the couch are probably pretty low. They’re not necessarily zero but they’re low. So start with the places that they might be and then move out from there. Now again, this doesn’t guarantee that I’ll find the keys but it’s going to be a lot faster and maybe I try that and it still doesn’t work. Then maybe eventually I have to resort to my algorithm approach but most of the time we use heuristics.
We have shortcuts that we use that allow us to skip a lot of potentially unnecessary steps. So in the next few videos we’ll look at some other types of heuristics that we use in our decision-making. We’ll also see the situations where they can lead us astray; they can lead us to think that we’ve found the answer when in fact we haven’t or we found an incorrect answer. Ok, I hope you found this helpful, if so, please like the video and subscribe to the channel for more.
Thanks for watching!
When solving a problem, choosing the right approach is often the key to arriving at the best solution. In psychology, one of these problem-solving approaches is known as an algorithm. While often thought of purely as a mathematical term, the same type of process can be followed in psychology to find the correct answer when solving a problem or making a decision.
An algorithm is a defined set of step-by-step procedures that provides the correct answer to a particular problem. By following the instructions correctly, you are guaranteed to arrive at the right answer.
An algorithm is often expressed in the form of a graph, where a square represents each step. Arrows then branch off from each step to point to possible directions that you may take to solve the problem. In some cases, you must follow a particular set of steps to solve the problem. In other instances, you might be able to follow different paths that will all lead to the same solution.
This article discusses how algorithms are used as an approach to problem-solving. It also covers how psychologists compare this approach to other ways to solve problems.
There are many different examples of how algorithms can be used in daily life. Some common ones include:
- A recipe for cooking a particular dish
- The method a search engine uses to find information on the internet
- Instructions for how to assemble a bicycle
- Instructions for how to solve a Rubik's cube
- A process to determine what type of treatment is most appropriate for certain types of mental health conditions
The upside of using an algorithm to solve a problem or make a decision is that yields the best possible answer every time. There are situations where using an algorithm can be the best approach:
- When accuracy is crucial: This is useful in situations when accuracy is critical or where similar problems need to be frequently solved. In many cases, computer programs can be designed to speed up this process. Data then needs to be placed in the system so that the algorithm can be executed to come up with the correct solution.
- When each decision needs to follow the same process: Such step-by-step approaches can be useful in situations where each decision must be made following the same process. Because the process follows a prescribed procedure, you can be sure that you will reach the correct answer each time.
The downside of using an algorithm to solve the problem is that this process tends to be very time-consuming. So if you face a situation where a decision needs to be made very quickly, you might be better off using a different problem-solving strategy.
For example, an emergency room doctor making a decision about how to treat a patient could use an algorithm approach. However, this would be very time-consuming and treatment needs to be implemented quickly. In this instance, the doctor would instead rely on their expertise and past experiences to very quickly choose what they feel is the right treatment approach.
Algorithms can be a great problem-solving choice when the answer needs to be 100% accurate or when each decision needs to follow the same process. A different approach might be needed if speed is the primary concern.
In psychology, algorithms are frequently contrasted with heuristics. Both can be useful when problem-solving, but it is important to understand the differences between them.
A heuristic is a mental shortcut that allows people to quickly make judgments and solve problems.
These mental shortcuts are typically informed by our past experiences and allow us to act quickly. However, heuristics are really more of a rule-of-thumb; they don't always guarantee a correct solution.
So how do you determine when to use a heuristic and when to use an algorithm? When problem-solving, deciding which method to use depends on the need for either accuracy or speed.
If complete accuracy is required, it is best to use an algorithm. By using an algorithm, accuracy is increased and potential mistakes are minimized.
If you are working in a situation where you absolutely need the correct or best possible answer, your best bet is to use an algorithm. When you are solving problems for your math homework, you don't want to risk your grade on a guess.
By following an algorithm, you can ensure that you will arrive at the correct answer to each problem.
On the other hand, if time is an issue, then it may be best to use a heuristic. Mistakes may occur, but this approach allows for speedy decisions when time is of the essence.
Heuristics are more commonly used in everyday situations, such as figuring out the best route to get from point A to point B. While you could use an algorithm to map out every possible route and determine which one would be the fastest, that would be a very time-consuming process. Instead, your best option would be to use a route that you know has worked well in the past.
Psychologists who study problem-solving have described two main processes that people utilize to reach conclusions: algorithms and heuristics. Knowing which approach to use is important because these two methods can vary in terms of speed and accuracy.
While each situation is unique, you may want to use an algorithm when being accurate is the primary concern. But if time is of the essence, then an algorithm is likely not the best choice.