Driver turn time follows one driver or tractor visit through declared arrival and departure boundaries. Trailer dwell follows one trailer through its own arrival, drop, service, readiness and pickup events. In drop-and-hook work the driver can leave quickly while the dropped trailer remains for many hours, so one clock cannot stand in for the other.
This specialist guide belongs to the Yard Management root. It also connects to The Gold Standard of Education | Learning That Transfers into Life and the How X Works hub. The worked cases are original teaching examples with stated inputs so their conclusions can be checked and transferred.
eduKateSG · Yard Management
Find your next learning step
Use this guide when a yard dashboard reports one dwell number, when a gate-to-gate improvement is presented as evidence that trailers clear faster, or when outside queues are excluded. The worked cases keep driver, tractor, trailer, container, shipment, gate, drop, pickup and bay events as separate identities and timestamps.
ROUTE 1 · CHAPTERS 1–3
Set up the distinction
Define the quantities, denominators and first worked case.
ROUTE 3 · CHAPTERS 6–8
Change the context
Change one premise, rebuild the result and track what remains comparable.
ROUTE 4 · CHAPTERS 9–10
Test limits and misconceptions
Separate the focused result from nearby claims requiring different evidence.
ROUTE 5 · CHAPTERS 11–12
Verify and explain
Use an evidence receipt, a transfer check and a concise final account.
Chapter contents
Set up the distinction · Chapters 1–3
1. Identify the entity before starting a clock
Work the calculation · Chapters 4–5
Change the context · Chapters 6–8
6. Decompose trailer dwell into readiness states
Test limits and misconceptions · Chapters 9–10
Verify and explain · Chapters 11–12
CHAPTER 1 OF 12 · Set up the distinction
1. Identify the entity before starting a clock
The short answer is that driver turn time belongs to a person or tractor visit, while trailer dwell belongs to a trailer asset or transport unit. This chapter treats identify the entity before starting a clock as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. One tractor enters with trailer A, drops it and exits with trailer B; the tractor visit ends even though trailer A remains Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the entities separate at the drop-and-hook event and therefore cannot share one departure timestamp The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. change the operation to live loading with the same tractor attached and state which identities remain coupled Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to use vehicle as one ID. It collapses tractor and trailer records and makes both durations ambiguous Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Some sites track containers or chassis separately as additional assets Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Preserve stable IDs and explicit relationship events rather than overwriting one vehicle field. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 2 OF 12 · Set up the distinction
2. Declare total and terminal turn boundaries
The short answer is that driver turn time may mean external-queue-to-final-departure or a narrower gate-to-gate or pedestal-to-pedestal interval, so the boundary must accompany the value. This chapter treats declare total and terminal turn boundaries as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. A driver joins the outside queue at 08:00, gates in at 08:15 and exits at 08:55; total turn is 55 minutes while gate-to-gate turn is 40 Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the fifteen-minute difference is real driver time located outside the gate boundary The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. move the queue checkpoint from the public road to a geofence 500 metres upstream and recompute total turn Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to compare a total-turn benchmark with an internal terminal measure. The names sound similar but the intervals differ Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. GPS, kiosk and gate timestamps can have different latency and coverage Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Store every boundary name, clock source, timezone, geofence and missing-event rule. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 3 OF 12 · Set up the distinction
3. Define trailer dwell with a stated start and end
The short answer is that trailer dwell should follow the same trailer between declared asset events such as gate-in to gate-out or drop to pickup. This chapter treats define trailer dwell with a stated start and end as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. Trailer A is dropped at 08:40 on Monday and hooked for pickup at 14:00 Tuesday, giving drop-to-hook dwell of 29 hours 20 minutes Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the trailer remains an asset in the yard after the original driver visit ends The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. change the endpoint from hook time to final gate-out at 14:25 and state why the dwell rises by 25 minutes Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to end dwell when unloading finishes. A ready trailer can still occupy yard capacity while awaiting pickup Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Gate-to-gate and drop-to-hook dwell answer different questions and can both be useful Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Retain trailer identity, start event, end event, event source, custody state and open-dwell status. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
The short answer is that the driver clock and trailer clock should be calculated independently from the same event ledger. This chapter treats work the drop-and-hook timeline as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. The driver queues at 08:00, gates in 08:15, drops trailer A at 08:40, hooks trailer B at 08:47 and exits 08:55, so total turn is 55 minutes; trailer A remains until Tuesday 14:00, so its drop-to-hook dwell is 29 hours 20 minutes Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. each subtraction uses events belonging to the entity named by the metric The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. delay trailer B readiness until 09:20 and recompute driver turn without changing trailer A dwell Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to report the 55-minute driver turn as trailer dwell. It discards the remaining asset occupancy Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. The example is an original teaching timeline and does not represent a named terminal Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Save the ordered event table, entity on each row, both boundary pairs, arithmetic and unit conversions. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 5 OF 12 · Work the calculation
5. Decompose the driver visit into operational states
The short answer is that turn time can be partitioned into outside queue, gate processing, travel, drop, hook, exception and exit intervals when event coverage supports it. This chapter treats decompose the driver visit into operational states as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. The 55-minute example contains 15 minutes outside queue, 25 minutes from gate-in to drop and 15 minutes from drop to exit Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. state decomposition shows where time moved when the total changes The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. reduce gate processing by five minutes but add five minutes waiting for the outbound trailer and verify that total turn stays constant Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to celebrate a faster gate scan without checking whether waiting moved deeper into the yard Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Overlapping tasks and coarse scans can make additive partitions approximate Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Preserve state definitions, event ordering, overlaps, unobserved time and reconciliation to the total. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 6 OF 12 · Change the context
6. Decompose trailer dwell into readiness states
The short answer is that trailer dwell should distinguish waiting for bay, service, post-service readiness and waiting for pickup when those states can be observed. This chapter treats decompose trailer dwell into readiness states as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. Trailer A waits six hours for a bay, spends two hours in service, becomes ready at 16:40 and then waits 21 hours 20 minutes for pickup Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the largest component identifies asset occupancy after operational service rather than driver processing The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. move service completion four hours earlier while leaving pickup fixed and show that total dwell stays unchanged but ready-wait grows Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to call all trailer dwell congestion. Some time may be planned storage or carrier pickup delay Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. State codes must reflect actual physical readiness rather than optimistic workflow updates Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Store bay events, service completion, release conditions, ready timestamp, pickup appointment and reason codes. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 7 OF 12 · Change the context
7. Compare live-load and drop-and-hook carefully
The short answer is that live-load operations often couple driver turn to service duration, while drop-and-hook can decouple the driver from the trailer’s later service and pickup. This chapter treats compare live-load and drop-and-hook carefully as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. A live-load driver waiting two hours at a bay records that time in turn, whereas a drop driver may depart before service begins Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. operating design changes which entity bears the wait even when total site work is similar The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. convert the worked drop-and-hook case to live load with service from 14:00 to 16:00 and calculate the attached driver’s visit duration Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to rank operating modes using driver turn alone. A faster driver visit can coexist with longer trailer inventory Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Labour, equipment pools, detention rules and network balance affect the broader decision Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Report operating mode, attachment state, service interval, driver clock and trailer clock together. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 8 OF 12 · Change the context
8. Keep appointments separate from actual clocks
The short answer is that appointment time is a planned reference and should not replace observed arrival, gate, drop or pickup events. This chapter treats keep appointments separate from actual clocks as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. A 08:30 appointment with queue arrival at 08:00 and gate-in at 08:15 shows early arrival but does not start trailer dwell unless that boundary is explicitly chosen Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. schedule adherence and elapsed duration answer different questions The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. move the appointment to 09:00 without changing physical events and identify which metrics change Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to calculate dwell from appointment time to departure. Early and late behaviour then contaminates asset duration Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Appointment windows and grace rules should be versioned Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Preserve planned time, window, actual event times, adherence calculation and duration boundaries separately. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 9 OF 12 · Test limits and misconceptions
9. Handle open dwell and censoring
The short answer is that a trailer still present at the reporting cutoff has right-censored dwell rather than a completed duration of zero or the current age treated as final. This chapter treats handle open dwell and censoring as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. A trailer dropped Monday at 08:00 and still present Tuesday at 08:00 has at least 24 hours of dwell, with its final duration unknown Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the cutoff supplies a lower bound while the end event remains absent The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. advance the report cutoff six hours and update current age without pretending a pickup occurred Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to exclude open trailers from average dwell. Long-staying assets then disappear from the metric Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Survival methods or age-bucket reporting may be needed when censoring is substantial Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Retain observation cutoff, present-state evidence, age, censoring flag and eventual late-arriving end event. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 10 OF 12 · Test limits and misconceptions
10. Use distributions rather than one mean
The short answer is that turn and dwell should be reported with percentiles, counts and boundary definitions because skew and tails matter operationally. This chapter treats use distributions rather than one mean as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. Nine 30-minute turns and one 300-minute exception average 57 minutes even though the typical completed visit is 30 Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the mean carries the exception burden while a median alone hides it The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. repair the exception and compare mean, median and ninetieth percentile Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to publish only an average and infer that every driver experienced it Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Small samples and censored trailer records can make high percentiles unstable Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Preserve distribution, sample size, censoring, percentile method, exclusions and exception categories. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
CHAPTER 11 OF 12 · Verify and explain
11. Audit shifted waits and timestamp incentives
The short answer is that a metric improvement is credible only if queues, manual holds and unrecorded pre-gate or post-ready time have not been shifted outside its boundary. This chapter treats audit shifted waits and timestamp incentives as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. Opening the official gate only after paperwork clears can reduce recorded gate-to-gate time while drivers still wait in a nearby holding area Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the operational burden remains even though the measured interval shrinks The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. add an upstream geofence and compare total turn before and after the process change Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to optimise the first and last recorded scans. Teams can improve the metric without improving flow Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. Privacy, public-road coverage and sensor error constrain external-queue measurement Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Cross-check GPS or geofence evidence, gate logs, appointment records, manual holds and driver feedback. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
The short answer is that a final report should name the entity, boundaries, operating mode, completed or censored status and distribution for each clock. This chapter treats build a two-clock yard receipt as a defined comparison. Keep driver ID, tractor ID, trailer ID, visit ID, shipment, appointment, external queue arrival, gate-in, drop, hook, bay-start, service-complete, ready, gate-out, censoring, timezone and correction history in separate fields. Two values can share a subject or unit and still answer different questions.
Worked example. A receipt states driver total turn 55 minutes from outside-queue arrival to exit, internal gate-to-gate 40 minutes, and trailer A drop-to-hook dwell 29 hours 20 minutes in a drop-and-hook operation Write the unit and basis beside every number, keep the intermediate result visible, and retain enough raw information for another reader to reproduce the answer without guessing a software default.
Why the result follows. the wording prevents one improvement from being claimed for the other entity The decisive operation is named before the conclusion. That makes a disagreement traceable to a denominator, measurement state, model or evidence threshold instead of leaving it as a vague conflict between labels.
Changed-context transfer check. delay outbound trailer B and advance trailer A pickup, then issue two independently updated metrics Rebuild the result from the altered premise. State the first intermediate value that changes, propagate it through the remaining steps, and identify any part of the earlier conclusion that still holds.
A common misconception is that nearby measurements are interchangeable. Here, The shortcut is to end with yard dwell improved. No reader can identify whose time, which boundary or which asset changed Correct the shortcut by naming the operation and the information it retains or discards, then show one case in which the values move differently.
Limits and caveats. The receipt supports diagnosis but does not alone choose staffing, appointment or detention policy Metric boundaries must be declared for the site and use case; a shorter clock can reflect a real improvement, a shifted wait or a changed timestamp boundary. Report any convention, instrument setting or model choice that can change the boundary of the claim.
Practical evidence check. Include site, timezone, IDs, mode, boundaries, raw events, corrections, censoring, sample distribution, exceptions, uncertainty and approved wording. Preserve the raw inputs, exclusions, units, uncertainty basis and calculation trail. A reader should be able to change one premise and obtain the transfer result without guessing the sample, conditions, measurement state or evidence basis used.
Contents · Previous chapter · Return to the Yard Management subject guide
Frequently asked questions
Is gate-to-gate time the same as total truck turn time?
Not always. Total turn can include the external queue before gate-in, while gate-to-gate or pedestal-to-pedestal time uses a narrower internal boundary.
When does trailer dwell end?
Use the declared operational question: hook, gate-out or another verified asset event. Publish the endpoint with the value.
Can fast driver turn prove the yard is uncongested?
No. Drop-and-hook can release drivers while trailers continue to wait for service, readiness or pickup.
What should happen to trailers still present?
Mark their dwell as open or right-censored and report current age. Do not exclude them or pretend the current age is a completed duration.
Continue through the verified reading routes
Start with the wider system
The Gold Standard of Yard Management · The Gold Standard of Education | Learning That Transfers into Life · How X Works hub
Compare the closest mechanisms
Appointment-arrival adherence and bay-start adherence · Service completion and bay release in a finite-buffer model · Unbroken bay time before promising an appointment
Choose the next lesson by reader job
Use the appointment-adherence lesson to keep planned and actual events separate, the bay-release lesson to distinguish service completion from physical release, and the unbroken-bay lesson before promising capacity from fragmented availability.
Authoritative sources and evidence checks
US DOT ROSA P — methodologies for reducing truck turn time · Bureau of Transportation Statistics — total truck turn and terminal boundaries · Bureau of Transportation Statistics — OSRA supply-chain indicators
US DOT and BTS sources support explicit truck-turn boundaries and asset-dwell measurement. The event ledger and arithmetic in this guide are original teaching examples rather than observations from a named yard.