Description
surplus = quantity*((firstWillingness+lastWillingness)/2-price).
Economic value comparisons need a common currency, period, quantity basis and definition of the relevant benefit or cost. A purchasing-power ratio, surplus segment or external-cost identity is only a contribution to a broader valuation.
surplus = quantity*((firstWillingness+lastWillingness)/2-price).
When to use this tool
Use Consumer Surplus One Linear Segment when checking a declared price, benefit or cost comparison.
How to use the tool and how it works
- Enter firstWillingness, lastWillingness, price, quantity. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read surplus. Use the output convention below.
Require nonnegative quantity. surplus = quantity*((firstWillingness+lastWillingness)/2-price).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstWillingness | First Willingness | Required. Finite number. |
| lastWillingness | Last Willingness | Required. Finite number. |
| price | Price | Required. Finite number. |
| quantity | Quantity | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| surplus | Surplus | Required. Finite number. |
{
"input": {
"firstWillingness": 20,
"lastWillingness": 10,
"price": 8,
"quantity": 4
},
"output": {
"surplus": 28
}
}Limitations and assumptions
- Willingness and price use currency per unit. This trapezoidal linear-segment surplus may be negative; no demand estimation, budget constraint or full consumer-surplus curve is constructed.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use appropriate empirical valuation and full system boundaries when assessing welfare, living standards or individual choices.
References
Similar or alternative tools
- Reservation Price Surplus One Unit
Return surplus = reservationPrice-actualPrice and participates when reservationPrice >= actualPrice.
- External Cost Private Social Gap
Return socialCost = privateCost+externalCost and gap = externalCost on one matching monetary basis.