Description
Compare observed travel time with a supplied catchment-edge limit.
Geographic activity records depend on location precision, boundary vintage, observation time, population denominator and access-window conventions. A travel-time budget differs from actual accessibility, and rectangular cell area does not establish privacy. Local shares and labels need the original survey and spatial definitions.
Compare observed travel time with a supplied catchment-edge limit.
When to use this tool
Use Service Catchment Edge Travel Gap when you already have suppliedTravelLimit, observedTravelTime and need to compare observed travel time with a supplied catchment-edge limit.
How to use the tool and how it works
- Enter suppliedTravelLimit, observedTravelTime. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read signedGap. Use the output convention below.
Return observedTravelTime-suppliedTravelLimit on a common time basis.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| suppliedTravelLimit | Supplied Travel Limit | Required. Finite number. |
| observedTravelTime | Observed Travel Time | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| signedGap | Signed Gap | Required. Finite number. |
{
"input": {
"suppliedTravelLimit": 12,
"observedTravelTime": 17
},
"output": {
"signedGap": 5
}
}Limitations and assumptions
- Signed inputs are retained; no route, service access, actual eligibility or acceptable travel limit is determined.
- 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 the actual route, service schedule, survey frame and boundary source when assessing mobility or access. Review disclosure across the full spatial dataset and linked records; a location label or cell-size product is not a complete privacy method.
References
Similar or alternative tools
- Travel Budget Time Constraint Margin
Check a supplied round-trip activity time budget.
- Service Access Opening Hour Overlap
Measure overlap between a supplied visit interval and service opening interval.