Rational decision making

Welcome to the World of Decision Making!

Ever wondered why you bought that expensive pair of trainers when a cheaper pair would do the same job? Or why you keep buying the same brand of cereal every week without even looking at the price?

In this chapter, we are going to dive into Rational Decision Making. We'll start with how Economists think we behave (like logical robots) and then look at the reality of why we often make choices that don't seem to make much sense!

1. The Starting Point: What is "Rationality"?

In Economics, being rational doesn't mean being "smart" in the way we usually mean it. It means that an individual makes a choice that results in the best possible outcome for themselves, based on the information they have.

The Two Main Assumptions

Traditional economic models are built on two very simple ideas about how people and businesses act:

1. Consumers aim to maximise Utility
Utility is just a fancy word for "satisfaction" or "happiness." Economists assume that every time you spend a pound, you are trying to get the absolute maximum amount of happiness possible from that money.

Example: If you have £2 and you're hungry, a rational consumer will choose the snack that gives them the most "yumminess" for that £2.

2. Firms aim to maximise Profits
Economists assume that businesses aren't there to make friends; they are there to make money. Every decision a firm makes—from who to hire to what price to set—is designed to make the gap between their total revenue (money coming in) and total costs (money going out) as large as possible.

Quick Review: The Logic Machine

Traditional Economics = Humans are "Utility Maximisers" and Firms are "Profit Maximisers."

Key Takeaway: Traditional models assume we are all perfectly logical, have all the information we need, and always choose the option that benefits us the most.

2. The Reality Check: Why We Aren't Always Rational

Don't worry if the "logical robot" idea feels a bit weird—it's because real life is messy! Modern economists (called Behavioral Economists) realized that humans don't always maximise their utility.

Here are the three main reasons the syllabus says we "fail" to be rational:

A. The Influence of Other People’s Behaviour

We are social creatures. Often, we don't choose what gives us the most utility; we choose what makes us fit in or look good to others.

Analogy: Think of "Keeping up with the Joneses." You might buy a specific brand of phone not because it has the best features for you, but because all your friends have it and you don't want to feel left out.

B. The Importance of Habitual Behaviour

Making a "rational" decision takes a lot of mental energy. To save time, our brains go on autopilot. We develop habits and stick to them, even if they aren't the "best" choice anymore.

Example: You might buy the same brand of toothpaste every month for five years. Even if a new brand comes out that is cheaper and better, you might not even notice it because you are acting out of habit.

C. Consumer Weakness at Computation

Let's be honest: mental math is hard! Many consumers struggle to calculate which deal is actually better.

Example: Is it better to get "33% extra free" or "Buy one get one half price"? Because many people find these calculations difficult (or are too busy to do them), they end up making a choice that doesn't actually maximise their money.

3. Summary Table: Rational vs. Irrational

Here is a simple way to remember the difference for your exam:

Rational Decision (Traditional View):
- Logic-based
- Maximises Utility (Consumers)
- Maximises Profit (Firms)
- Uses all available info

Irrational Decision (Alternative View):
- Socially influenced (Peer pressure)
- Habit-based (Autopilot)
- Computational weakness (Bad at math)

Memory Aid: The "H.C.S." Trick

If you need to remember why consumers are not rational in an exam, remember H.C.S.:

• H - Habits (We do what we've always done)
• C - Computation (We aren't great at the math)
• S - Social (We copy what others do)

Common Mistakes to Avoid

Mistake 1: Thinking "Utility" is only about money.
Correction: Utility is about satisfaction. If buying an expensive fair-trade coffee makes you feel good ethically, that is you maximising your utility!

Mistake 2: Confusing "Irrational" with "Stupid."
Correction: In Economics, "irrational" just means your decision didn't follow the strict rule of utility maximisation. Buying a gift for a friend is "irrational" in a cold, robotic model because you are giving away your resources, but it's a very human thing to do!

Quick Review Box

Prerequisite Check: Remember that ceteris paribus (all other things being equal) is usually applied to these models.

Checklist:
1. Can you define Utility? (Satisfaction)
2. What do firms aim for? (Profit Maximisation)
3. List 3 reasons why we aren't always rational (Social pressure, Habit, Poor math skills).

Key Takeaway: While traditional Economics assumes we are utility maximisers, in reality, our habits, social circles, and difficulty with numbers often get in the way of "perfect" decision making.