Description
Sum required time and subtract from available for signed buffer.
Food access records may describe travel time, eligibility, household equivalents or service coverage. Each summary depends on its supplied denominator and classification; it is not a complete measure of household food security.
Sum required time and subtract from available for signed buffer.
When to use this tool
Use Market Access Time Buffer when you need a transparent access, eligibility or coverage calculation.
How to use the tool and how it works
- Enter availableTime, outboundTravel, returnTravel, transactionTime. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read requiredTime, buffer. Use the output convention below.
Require nonnegative available, outbound, return and transaction time. Sum required time and subtract from available for signed buffer.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| availableTime | Available Time | Required. Finite number. |
| outboundTravel | Outbound Travel | Required. Finite number. |
| returnTravel | Return Travel | Required. Finite number. |
| transactionTime | Transaction Time | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| requiredTime | Required Time | Required. Finite number. |
| buffer | Buffer | Required. Finite number. |
{
"input": {
"availableTime": 100,
"outboundTravel": 20,
"returnTravel": 30,
"transactionTime": 10
},
"output": {
"requiredTime": 60,
"buffer": 40
}
}Limitations and assumptions
- All times share units. A nonnegative buffer does not establish actual transport, affordability, accessibility or reliable opening hours.
- 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
Review the actual household context, service rules and source records. Combine appropriate field assessment with quantitative summaries when access, equity or nutritional needs matter.
References
Similar or alternative tools
- Food Access Window Share
Sum open durations and durations satisfying all flags; divide the latter by open time or return flagged zero.
- Food Access Market Travel Cost Share
Return total outlay and nonfood access-cost share.