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Understand the key parameters in activity scheduling models for effective transportation planning. Explore the factors influencing costs, risks, and comfort levels to optimize schedules. Learn about different approaches and tools used in scheduling models.
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Preferred citation style • Axhausen, K.W. and K. Meister (2007) Parameterising the scheduling model, MATSim Workshop 2007, Castasegna, October 2007.
Parametrising the scheduling model KW Axhausen and K Meister IVT ETH Zürich October 2007
End of detour – So why parametrisation ? • We use uniform current wisdom values • We need: • Locally specific values • Heterogenuous values
Degrees of freedom of activity scheduling • Number (n ≥ 0) and type of activities • Sequence of activities • Start and duration of activity • Group undertaking the activity (expenditure share) • Location of the activity • Connection between sequential locations • Location of access and egress from the mean of transport • Vehicle/means of transport • Route/service • Group travelling together (expenditure share)
2007: Planomat versus initial demand versus ignored • Number (n ≥ 0) and type of activities • Sequence of activities • Start and duration of activity • Group undertaking the activity (expenditure share) • Location of the activity • Connection between sequential locations • Location of access and egress from the mean of transport • Vehicle/means of transport • Route/service • Group travelling together (expenditure share)
Generalised costs of the schedule • Risk and comfort-weighted sum of time and money expenditure: • Travel time • Late arrival • Duration by activity type • Expenditure
Generalised costs of the schedule • Risk and comfort-weighted sum of time and money expenditure: • Travel time • By mode (vehicle type) • Idle waiting time • Transfer • Late arrival by group waiting and activity type • Duration by activity type • By time of day/group • Minimum durations • By unmet need (priority) • Expenditure
Generalised costs of the schedule • Risk and comfort-weighted sum of time and money expenditure: • Travel time • By mode (vehicle type) • Idle waiting time • Transfer • Late arrivalby group waitingand activity type • (Desired arrival time imputation via Kitamura et al.) • Duration by activity type • By time of day/group • Minimum durations • By unmet need (priority) (Panel data only) • Expenditure – Thurgau imputation; Mobidrive: observed
Approaches • Name Need for Estimation • unchosen • alternatives • Discrete choice model Yes ML • Work/leisure trade-off No ML • W/L & DC (Jara-Diaz) (Yes) ML • Time share replication (Joh) No Ad-hoc • Rule-based systems No CHAID etc. • Ad-hoc rule bases No Ad-hoc
Criteria • How reasonable is the approach ? • How easily can the objective function by computed ? • Are standard errors of the parameters easily available ? • Can all our parameters be identified ? Can we estimate means only ? • What is the data preparation effort required ? • Do we need to write the optimiser ourselves ?
Frontier model of prism vertices (Kitamura et al.) • Idea: Estimate Hägerstrand’s prisms to impute earliest departure and latest arrival times • Approach: Frontier regression (via directional errors) • Software: LIMDEP
PCATS (Kitamura, Pendyala) • Not a scheduling model in our sense • Idea: Sequence of type, destination/mode, duration models inside the pre-determined prisms • Target functions: • ML (type, destination/mode, number of activities) • LS (duration) • Software: Not listed (Possibilities: Biogeme; LIMDEP)
TASHA (Roorda, Miller) • Not quite a scheduling model in our sense • Idea: Sequence of conditional distributions (draws) by person type: • Type and number of activities • Start time • Durations • Rule-based insertion of additional activities • No estimation as such; validation of the rules
AURORA - durations (Joh, Arentze, Timmermans) • Idea: • Duration of activities as a function of time since last performance ( time window and amount of discretionary time) • Marginal utility shifts from growing to decreasing • Target function: Adjusted OLS of activity duration under marginal utility equality constraint • Software: Specialised ad-hoc GA • See also: Recent SP, MNL & non-linear regression (including just decreasing marginal utilities functions)
W/L tradeoff with DCM (Jara-Diaz et al.) • Idea: Combine W/L with DCM to estimate all elements of the value of time • Value of time savings in activity i • μ: Marginal value of time • λ: Marginal value of income • μ/λ: Value of time as a resource
W/L tradeoff with DCM (Jara-Diaz et al.) • Idea: Combine W/L with DCM to estimate all elements of the value of time • Target function: • Cobb-Douglas for the work/leisure trade-off • DCM for mode choice • Estimation: LS for W/L trade-off; ML for DCM
Discrete continuous multivariate: Bhat (Habib & Miller) • Idea: Expand Logit to MVL and add continuous elements • Target function: closed form logit • Estimation: ML • Example: Activity engagement and time-allocated to each actvity
Issue: • Various frameworks for activity participation and time allocation • No joint model including timing