An assumption is a condition you hold fixed so the reasoning works. A limitation is what the result cannot tell you. Together they let you evaluate an economic result without turning it into an opinion.
This lesson is part of economic reasoning and evaluation. For the data side of the same habit, see evidence-based economic answers.
How do you turn an opinion into a conditional statement?
Replace “should” and “unfair” with “if” and “then”. An opinion says how the world ought to be. A conditional says what follows from stated conditions, and that is what an economics answer can defend.
| Opinion | Conditional statement |
|---|---|
| The price cap is unfair to sellers | If sellers must charge below the market price, the quantity they offer falls |
| The cap should be removed | Under these assumptions, the cap creates a shortage |
The second column can be checked against numbers. The first column cannot.
Worked example: a price cap on nasi lemak
In a fictional town, the market price of a packet of nasi lemak is RM5. The town council sets a maximum price of RM4.
At RM4, buyers want 120 packets a day and sellers offer 80. The shortage is 120 − 80 = 40 packets.
Assumptions to state: only the price rule changes, sellers follow the cap, and no other supplier enters.
Conclusion: “Under these assumptions, the cap creates a shortage of 40 packets a day at RM4.”
Limitations to state: the numbers do not show which buyers miss out on the 40 packets, so they cannot show who gains. They also say nothing about whether sellers reduce portion size or quality.
That is a complete evaluation. It names what the model shows, what it assumed and what it cannot reach.
Which mistakes cost marks?
- Smuggling in a value. Writing “sellers suffer” when the data show only a lower quantity.
- Silent assumptions. Giving a conclusion without saying what was held constant.
- Overreach. Claiming the cap “helps the poor” when the table has no information on buyers’ incomes.
The fix is to reread your last sentence and ask: does the table or model show this, or am I adding it?
Check yourself
A fictional council doubles the parking fee in Taman Sinar, so an hour now costs RM2 instead of RM1. A student writes: “This is a bad policy because drivers will be angry.” Rewrite the sentence as a conditional statement and add one limitation.
Answer
A possible rewrite: “If the fee doubles and nothing else changes, the quantity of parking hours demanded is likely to fall, because parking costs more.”
A limitation: the statement does not show whether nearby shops gain or lose customers, because no figures on shop sales are given.
The original sentence relied on feelings. The rewrite names the condition, the direction and what remains unknown.
What to study next
Practise the skill in the economic reasoning and evaluation practice. The supply and demand diagram reasoning explorer shows how a cap creates a gap between demand and supply.
To have a teacher help with evaluation wording, see online one-to-one Economics tuition.