A want is a desire for a good or service. Effective demand is a want backed by both willingness to pay and the ability to pay at a stated price. Only effective demand shows up in a market.
This lesson belongs to scarcity, choice and opportunity cost because wants are unlimited while resources, including people’s incomes, are limited. That limit is what turns a want into a choice.
What turns a want into effective demand?
Three questions, in order, decide it:
- Does the person want it? If not, there is no demand at all.
- Are they willing to pay this price? A student may want a laptop but think RM1,800 is too much.
- Can they pay this price? Willingness without money, savings or credit they can actually use does not count.
Only when the answers are all yes is it effective demand. Notice that the price is part of the test: change the price and the answer can change.
Worked example
A fictional market, Pasar Seri Bayu, sells a handmade bag at RM80. Five people want one.
| Person | Wants it? | Willing to pay RM80? | Can pay RM80? | Effective demand at RM80? |
|---|---|---|---|---|
| Aini | Yes | Yes | Yes (has RM120) | Yes |
| Bala | Yes | Yes | No (has RM45) | No |
| Chen | Yes | No (thinks it is worth RM60) | Yes (has RM200) | No |
| Dewi | Yes | Yes | Yes (has RM90) | Yes |
| Eric | No | n/a | Yes | No |
Effective demand at RM80 is 2 bags, from Aini and Dewi. The want count is 4 (Eric does not want one).
Now the seller cuts the price to RM55.
Bala is willing and now has RM45, so he still cannot pay. Chen thinks it is worth RM60, so he is now willing, and he can pay. Effective demand at RM55 is 3 bags: Aini, Chen and Dewi. Bala is still outside, because RM45 is below RM55.
The lesson: wants stayed the same at 4, but effective demand changed from 2 to 3 because the price changed.
The mistake to watch for
Mistaken answer: “There are 4 people who want a bag, so demand for the bag is 4.”
The student counted wants and ignored willingness and ability to pay.
To correct it, test each person against both conditions at the stated price. In economics, “demand” in the market sense is effective demand, so the answer at RM80 is 2.
A second slip is saying a want “has no cost”. Wants matter, but they only change market outcomes once they turn into effective demand.
Check yourself
1. Sara wants a bicycle priced at RM400. She has RM150 and no way to borrow. Does she have effective demand at RM400?
Show answer
No. She wants it and may be willing, but she cannot pay RM400. It is a want, not effective demand.
2. A fictional café sells a cake at RM12. Kumar has RM50, likes cake, but says the cake is only worth RM8 to him. Effective demand at RM12?
Show answer
No. He has the ability to pay but is not willing at RM12. If the price fell to RM8, he would have effective demand.
3. Using Pasar Seri Bayu, what is effective demand at RM45? Assume Aini, Bala, Chen and Dewi keep the values above, and Chen’s willingness is up to RM60.
Show answer
At RM45: Aini yes, Bala yes (he has RM45 and is willing), Chen yes, Dewi yes. Effective demand is 4 bags.
Where this leads next
Next, look at the resources that make goods in classifying a productive resource. If you want to see how price changes alter quantities, the demand and supply shift explorer lets you try fictional numbers and shows the difference between a movement and a shift.
Some students can state the definition and still struggle when a case study hides the money condition. In online one-to-one Economics tuition, our teachers work through case wording like this one sentence at a time.