Title: Financing
1Financing
2Financing c. 1920
3Financing c. 1996
4Federal Highway Revenue by User Class
5Freight Movement (Share of Ton-km)
6Federal Transportation Budget
7Transportation Revenues and Revenue Raising
Instruments by Mode FY 1999
8Public-Private Partnerships
- Rising infrastructure costs and social demands gt
tight government budgets and public resistance
(tax increases) - Mutually agreed government agencies and private
business - Private sectors fulfilling responsibilities
9PPP Types and Model
- Main Types of PPP (USGAO, 1999)
- Build-Own-Operate (BOO)
- Build-Opeate-Transfer (BOT)
- Buy-Build-Operate (BBO)
- Design-Build-Operate (DBO)
- Build-Develop-Operate (BDO)
- Similarities (European)
- Design-Build-Finance-Maintain (DBFM, The
Netherlands Case) - Design-Build-Finance-Operate (DBFO, Ireland)
10USA PPP Experience
- The United States Large PPP projects in the road
sector - Alameda Corridor (Long Beach-Los Angeles, CA)
- Dulles Greenway, Virginia
- State Route 125 South Tollway (San Diego County,
CA) 4 lane 11.2 mile highway - Western Loop (Richmond, Virginia)
- Route 3 (Massachusetts)
- Highway E-470 (Aurora, Colorado) 47 mile toll
road
11Alameda Corridor
- Alameda Corridor (Long Beach-Los Angeles, CA)
- History
- Ports Advisory Committee (October 1981)
- Route Alternatives (1984)
- Alameda Corridor Transport Authority (1989)
- The US DOT 400 M, 30 year loan (1998)
- Objectives
- Reduce Highway traffic delays
- Increase Rail productivity
- Reduce Accidents
- Improve Air quality
12Alameda Corridor
- Related Projects
- San Gabriel Valley 55 rail crossings, LA County,
8 year project, 912 M - Pacific Coast Highway Separate Grade (PCH)
30,000 commuters daily, 1 mile long - Discussion
- Completion on time and on budget
- Design-Build instead of Design-Bid-Build
- Creation of 700,000 jobs (2020, port growth)
- Environmental benefits truck traffic (23
reduction), delays at grade crossings (90
reduction), noise and vibrations (90 reduction)
13Dulles Greenway, Virginia
- History
- Originated 1988 Virginia Assembly authorized
private toll roads - Construction initiated in 1993 and concluded in
1995 - Consists 7 interchanges, 36 bridges, a toll
plaza, 12 ramp toll barriers, 4 operational
lanes. - Extension 14-mile western extension, Dulles Toll
road.
14Financing Regulation
- The Case of Spring Load Restrictions.
- Current Truck weights restricted during spring
thaw - Alternative Trucks allowed but charged for the
damages imposed.
15How Much Revenue?
- The revenue required to compensate road owners
for the additional damage associated with lifting
the SLR in Minnesota can be estimated.
16Estimate of Statewide Annual Cost
- The annualized cost of a net present value of
127,457,204 at 3.5 interest over 42.5 years is
therefore 5,806,768. - Different assumptions will yield different
annualized costs.
17Diesel Fuel Surcharge
- Presently the tax on diesel fuel is 0.20/gallon
- In total, 652,549,000 gallons of Special fuels
were consumed in Minnesota in 2002 - This implies to cover the costs of removing the
SLR on 7 and 9-ton roads, a year-round
0.01/gallon diesel fuel surcharge would be
sufficient
18Annual Fee
- There were 34,729 truck/tractors and 48,938 farm
trucks in Minnesota in 2002 - Allocating the cost uniformly to all
truck/tractors and farm trucks would give a
charge of 69.40 per farm truck and truck/tractor
vehicle per year to recover the additional damage
to roads associated with lifting the SLR on 5 and
7-ton roads.
19Weight Distance Tax
- In 1999, Oregon voters passed Measure 76, and
placed in the state constitution the idea of
cost responsibility, ensuring that cars and
trucks each pay their fair share. - The Oregon Highway Cost Allocation Study is
conducted biennially to support highway-financing
decisions. - The 2003 report states that light vehicles
(weighing 3,636 kg (8,000 pounds) or less) should
pay 66.6 of state highway user revenue, and
heavy vehicles should pay the remaining 33.4. - Employing a weight-distance tax in Minnesota
would require a change in revenue policy well
beyond what is required to recover costs from the
Spring Load Restrictions, but remains a good idea
to maximize both fairness and efficiency in the
highway financing system.
20Permitting System
- A new SLR permitting system would require a new
regulatory apparatus. - Though it would be possible in principle to
charge directly based on use, the enforcement
required to do so would entail a significant
transactions cost that may obviate the gains from
policy change.
21How Should the Revenue Be Spent?
- Because most of the economic burden associated
with lifting the Spring Load Restriction would be
borne by local governments (counties and
municipalities), the revenue that is collected to
recover the costs of the additional pavement
damage associated with lifting the SLR should be
dedicated to local governments to spend on
maintaining and rebuilding roads. Local
governments would then need to prioritize
projects based on local engineering and other
information.
22Discussion (1)
- The highway system has a disjoint control of
trucks (owned by trucking firms) and pavements
(owned by governmental road agencies), which has
created a number of extra costs that proper
management of the system might avoid. - Pavements are rated for different loads of
trucks roads are restricted to 5-ton, 7-ton,
9-ton, and 10-ton axle weight trucks. - Shipments across this network are constrained by
the lowest weight limit permitted on the roads to
be used (or risk violation though weight
enforcement off the interstate highways is very
sparse). - Some roads should be upgraded, some trucks should
have more axles, but the disjoint nature of the
control makes this coordination difficult.
23Discussion (2)
- The first solution to these problems lies in
rethinking highway financing. The ability to
charge truckers different amounts for different
roads would put the proper incentives for
socially beneficial behavior back in the system - A second solution, to improve materials to the
point that they are too cheap to meter, that is
so that they are sufficiently strong that it
doesnt matter the load using them (within
reason), is the analog to building your way out
of congestion. Laying pavements with near zero
variable (per use) costs may be technically
possibly, but their upfront fixed (one time)
costs are likely to be very high.
24Models
25- All forecasts are wrong, some forecasts are more
wrong than others.
26Rise of the Automobile/ Highway System
- Do cars and cities mix?
- Can new highways (expressways, freeways) be used
to reshape cities? - Original interstate plan proposed to bypass city
centers. Cities demanded connection. - Some argued highways would help recentralize
cities (e.g. Regional Plan for New York), Other
argued highways could be force for
decentralization into Garden Cities (e.g.
Regional Planning Association of America)
27History of Transportation Models
- The Chicago Area Transportation Study (1955) (Led
by J. Douglas Carroll) - The study cost 3.5 million and took seven years
to complete. - Considered
- the foundational study of urban transportation
planning in America (MacDonald 1988 Weiner
1987) - a model of "rational planning" model (Black
1990).
28Before and After
- Detroit Metropolitan Area Transportation Study
(1953-1955) (Under J. Douglas Carroll). Mostly
done by hand. - Chicago Area Transportation Study (1955)
- Washington Area Traffic Study (1955)
- Baltimore Transportation Study (1957)
- Pittsburgh Area Transportation Study (1958)
- Hartford Area Traffic Study (1958)
- Penn-Jersey Transportation Study (1959)
- FHWA Planpac Mainframe Model (1960s)
- UMTA Urban Transportation Planning System
Mainframe Model (1960s) - Merger of two models to UTPS in 1970s
- PC implementation (Tranplan, MinUTP, Emme/2,
QRSII, Tmodel,Transcad, System2) in 1980s
29CATS
- Agency of City of Chicago, Cook County, State of
Illinois, and US Bureau of Public Roads - Created in 1955 to analyze travel behavior,
forecast future needs, and develop long range
plan. - In peak year (1956) employed 369 people,
including planners and engineers. - Followed principles of rational planning
- Used quantitative methods to establish technical
expertise - Developed first computer-based regional models
30Rational Planning Model
- Identify needs
- Set objectives
- Develop options
- Evaluate options
- Select best option
- Implement policy
- Evaluate outcome
31Critique of rational planning
- Top-down (Newtonian model)
- Identical people/groups (aggregation)
- No externalities
- No dynamics, everything in equilibrium
- Everything is objective
- Missing feedbacks
- Others lt_______gt
32CATS Goal To secure a transportation system for
the Chicago area which will reduce travel
frictions within the constraints of safety,
economy, and the desirable development of land"
- Objectives
- increasing speed,
- increasing safety,
- lowering operating costs,
- economizing on new construction,
- minimizing disruption, and
- promoting better land development.
33Inputs and Outputs
- CATS Input Data
- travel,
- land use,
- networks
- desire lines
- vehicle counts
- origin-destination surveys
- home interview surveys
- CATS Forecasted
- population,
- population distribution,
- per capita income,
- auto ownership,
- travel behavior
34Questions
- Did desire lines reflect desires?
- Is past behavior reflective of future behavior?
- Can the future be predicted
- Is the future independent of decisions, or are
prophesies self-fulfilling? - How do we know if forecasts were successful?
Against what standard are they to be judged? - What values are embedded in the planning process?
What happens when values change?
35Purposes of Modeling
- Estimation in the absence of data
- Forecasting
- Scenario Testing (alternative land uses,
networks, policies) - Project Planning/Corridor Studies
- Growth Management/Development Regulation/Public
Facility Adequacy - Manage Complexity, when eyeballs are
insufficient, different people have different
intuitions - Understanding travel behavior
- Influence Decisions
36Outputs from Models
- Flows on links,
- Speeds on links
- Origin Destination pattern
- Mode Split
- Other desired outputs
- Emissions (requires post-processor, knowledge of
fleet composition, dynamics of speeds) - Time of day splits
- Change in land use as a result of network
37Modeling Process
- Specification
- Estimation
- Implementation
- Calibration
- Validation
- Application
- Each step feeds back to previous steps.
38Four-Step Models
39Network Framework
- zone centroids - special node, number of a zone,
identified by x y coordinate - nodes number identified by X Y coordinate
- links, indexed by from and to nodes (including
centroid connnectors) - turns, indexed by at, from, and to nodes
- routes, indexed by a series of nodes (e.g. a bus
route) - paths, indexed by a series of nodes from origin
to destination. - modes vehicle lines, transit lines.
40Matrices
- Indexed by Traffic Analysis Zones (including
External Stations) - 4 types
- scalar,
- vector (origin),
- vector (destination),
- full (interaction)
41Scalar Matrix
- Scalar
- For example ms01 price of fuel ( per gallon)
- ms01 1.37
ms01 value
42Matrix Vector Origin
- Example ms01 Households per zone
1 .
2 .
3 .
.
.
I .
1 10
2 17
3 12
.
.
I .
43Matrix Vector Destination
- Destination (j)
- Example Jobs per zone
1 2 3 . . J
. . . . . .
1 2 3 . . J
18 3 560 . . .
44Matrix Full
- Combine Origin and Destination matrices
- For instance Zone to Zone Trips (Trip Table)
45Purpose
- Trips are "produced" at an origin and "attracted"
to a destination. Trips are categorized by
Purposes, the activity undertaken at a
destination location - Typical purposes are
- Home
- Work
- Shop
- School
- Eat Out,
- Social/Recreational
- Medical
- Banking
- Other
- Often categories are dropped and lumped into the
catchall Other
46Politics of Modeling
- Try to be neutral arbiter to maintain credibility
for future applications - Influence is maximized when the only game in town
... try to avoid dueling models - Modeling is a process not a project, responses
must be timely, which requires having the model
set up to answer questions, not setting it up
after the question is asked - Spin your own results, don't just dump numbers on
someone's lap, give the interpretation yourself. - Only model when necessary, avoid the problem that
if your only tool is a hammer everything looks
like a nail.
47Future of Modeling
- Transsims - activity based ... follow individuals
rather than aggregates - Uses simulation and stochastic distributions
- Problems
- Data needs are huge
- computation intensity
- Complexity
- Accuracy
- Still no good answer for trip distribution (which
requires job matching to be disaggregate) - Modeling imperfect information, especially
routing - Integration of components
- Land-use transportation models
48Land Use Models
- Objective To predict where new land uses will
occur, their density, number of units, etc. - Land Use f (Accessibility - from travel demand
model, other things)
49The Seven Deadly Sins of Models (Lees Requiem)
- 1) Hypercomprehensiveness Meaning that the
models tried to replicate too complex a system in
a single shot, and were expected to serve too
many different purposes at the same time. - 2) Grossness In a way, the converse of
hypercomprehensiveness. Even though they tried
to do too much and serve too many purposes, their
results or outputs were too coarse and
aggregate, too simplistic to be useful for
complicated and sophisticated policy
requirements. - 3) Data Hungriness Even to produce, gross
outputs (a few variables), the models required us
to input many variables for many geographic
units, and from at least several time periods in
order to produce approximate projections, and
very often we could not afford the data
collection efforts needed to run the models. In
other instances, data simply didn't exist at the
levels of specificity which would be
appropriate to run them. - 4) Wrongheadedness Lee meant that the models
suffered from substantial and largely
unrecognized deviations between the behavior
claimed for them and the variables and equations
which actually determined their behavior. As an
example, when regional averages were used to
calibrate models, but forecasts were made for
local areas, the models deviated from reality
because of specification errors which were often
not even recognized by their users.
50Seven Deadly Sins (continued)
- 5) Complicatedness Even though when you looked
at them through one set of lenses the models
seemed terribly simplistic, when looked at
through another set of lenses they were
outrageously complex. Too simplistic in
replicating urban economic and social processes,
the models were too complex in their
computational algorithms. Errors were multiplied
because there were so many equations, spatial
units, and time periods. Even the theoretical
notion of the model or its representation of an
urban process was grossly simplistic compared
with reality. Often, the user didn't know how
the errors were propagated through series of
sequential operations and sometimes we needed to
use systematic adjustments or "correction
factors" to make the models more realistic even
though we did not completely comprehend the
sources of all the errors and could not interpret
the correction factors in real-world terms. - 6) Mechanicalness Lee meant that we routinely
went through many steps in a modeling process
without completely understanding why we did so,
and without fully comprehending the consequences
in terms of validity or error magnification. He
stated, for example, that even rounding errors
could be compounded beyond reasonable bounds by
mechanical steps taken to calibrate and apply
many models without the user's knowledge. - 7) Expensiveness The costs of the models,
derived from their grossness, data hungriness,
complicatedness, and so on, placed them beyond
the financial means of many agencies, or depleted
the resources of agencies so much that the very
use of models precluded having the resources
available to improve them or to fine tune them to
make them appropriate to their applications.
51Seven Challenges for Land Use Models (Landis)
- 1. Models - microbehavioral (actors and
agents)Social Benefit/Social Action - 2. Simulation - multiple movies/scenarios
- 3. Respond to constraints and investments
- 4. Nonlinearity - path dependence in
non-artifactual way (structure and outcomes,
network effects) - 5. spatial vs. real autocorrelation, emergence -
new dynamics, threshold network effects - 6. preference utility diversity and change over
time - 7. Useful beyond calibration periods. Embed
innovators and norming agents. Strategic and
response function.
52Four Ways to Improve Models (Lee)
- Models should be made more transparent to users
and policymakers. - Models should combine strong theoretical
foundations, objective information, and
wisdom or good judgment. Without these elements,
they remain exercises in empty-headed empiricism,
abstract theorizing, or false consciousness of
what is actually going on in our urban areas. - We should start with problems and match our
methods to the needs of particular situations,
gathering no more information and using no more
modeling complexity than is really needed. - We should build the simplest models possible,
since complex models do not work well, and
certainly are unlikely to be understood by those
who are asked to act on the basis of the model
outputs.
53QUESTIONS?
54Definitions
- Speed (V) Distance per Unit Time (e.g. MPH) -
often called Velocity, measured over space and
time. - Flow (Q) Vehicles per Unit Time (e.g. Vehicles
per hour) - often called Volume, measured at a
location over time - Density (K) Vehicles per Unit Distance (e.g.
Vehicles per Miles) - often called concentration,
measured over a segment instantaneously - Detector Occupancy (k) - Percent of time a
detector is occupied - convert to density if
vehicle length is known.
55Fundamental Diagram
56Space-Time Vehicle Trajectories
57Queueing
58Trip Generation Production and Attraction
- The number of trips produced or attracted to a
purpose in a zone are described by trip rates (a
cross-classification by age or demographics is
often used) or equations. - For instance trips produced from or attracted to
homes in a zone is described as a function of - Th f( housing units, household size, age,
income, accessibility, vehicle ownership). - From or to work
- Tw f ( jobs(square feet of space by type,
occupancy rate)) - From or to shop
- Ts f (number of retails workers, type of
retail, square foot, location, competition) - Clearly accessibility and vehicle ownership
require knowing something about the network, and
so may have to be solved recursively
59Trip Generation Balancing
- The number of trips produced (at home) from home
to work must equal the number of trips attracted
(at work). Two distinct models may give two
results. Either assume one model or the other is
correct and adjust the second, or split the
difference.
60Activity Analysis
- Frequency- How many times the trip is made per
day - Scheduling-the order in which the trips are made
- Activities-home, work, shop other
(Non-Discretionary). - Schools, church, visit friends,
recreation, visit doctor (Discretionary). - Patterns HWH, HWSH, and HWHSH.
- These are a function of sex, age, employment,
status, income, auto availability. - Important things to note in household study are
the household size (more predictable), household
structure (less predictable). - Location/accessibility studies involve feedback.
- Dwelling unit types are obtained from the land
use pattern and are an indicator of the income,
race, household structure. They are single units
and multi-family types. - Time of day The time of day can be derived from
the pattern and duration of activities.
Scheduling models give the pattern of activities
and not how long each activity takes place. - In a trip generation framework the peak hour
factor used is a constant and is a function of
congestion.
61Trip Distribution
- Estimate the number of trips going from zone i to
zone j for each purpose. This requires the
travel time (and cost) between zones (Cij) and
the trips produced or attracted to each zone
e(.g. Th(i), Tw(j)).
Destination Origin 1 2 3 . . J
1 Cij
2
3
I
62Trip DistributionImpedances
- This table of impedances requires knowing the
congested travel time on the network, which
itself requires knowing demand, and so may
require a recursive solution method of some kind
(i.e. feedback). - Interaction between zones is often described by a
gravity model, in analogy to Newton's Laws of
Gravitation. While 1/Cij2 was used in the past,
now a negative exponential form is preferred.
63Critique of Gravity Model
- Meyer and Miller (1984) claim a "lack of credible
theoretical basis" for the gravity model, on the
other hand, it is simply the law of demand, as
the cost of interaction increases, the level of
interaction decreases. The only issues are - (1) What is the shape of the curve
- (2) What else effects demand (i.e. the model is
incomplete).
64Negative Exponential Form
65Opportunities
66Resulting Trip Distribution
67Entropy Maximization
Typically Trips can be represented as a function
of productions (P), attractions (A) and
Costs/Times (C) such as Tij f(Aj, Pi, Cij)
Solve iteratively for Ki and Kj
68Mode Choice
- Estimate the number of trips from each zone to
each zone by purpose that take mode m.
Where, Cmij is the generalized cost containing
the fares, waiting time, parking cost, transit
environment access etc. Um is the utility of that
particular mode to a person.
69Variables in Mode Choice Models
- Travel Time of trip
- Travel time to access mode
- Wait Time f(headways of transit vehicles)
- Transfer Time
- Fare
- Parking Costs
- Tolls
- Alternative Specific Constant
- Other Qualitative Data (Sidewalks, Bus Shelters)
70Relationship of Logit and Gravity
- The observant student will note that the
functional relationship between the modern
gravity model and the logit mode choice model are
very similar, enabling simultaneous choice models
to be easily developed. The key difference is
that the gravity model is typically much more
aggregate.
71Independence of Irrelevant Alternatives
- Property of Logit (but not all Discrete Choice
models) - If you add a mode, it will draw from present
modes in proportion to their existing shares.
72Route Assignment
- Auto Assignment This is nothing but how
travelers choose to go from A to B. Traffic is a
very dynamic phenomenon. - Wardorps Users Equilibrium Principle Each user
acts to minimize his/her own cost, subject to
every other doing the same Travel times are
equal on all used routes and lower than on any
unused route. What people choose is efficient for
them which however need not be efficient for the
network. - Wardorps System optimal Principle Each user
acts to minimize the total travel time on the
system. - Volume Delay Function (VDF) As the traffic flow
on the link increases, the travel time on the
link increases. The cost that a driver imposes on
others is called the marginal cost. The travel
time for the other drivers increases because of a
particular driver. While dealing with traffic
assignment we deal with average cost but while
dealing with pricing etc. we consider marginal
cost.
73Conservation of Flow
- An important factor in road assignment factor is
the conservation of flow. This means that the
number of vehicles entering the intersection
equals the number of vehicles exiting the
intersection for a given period of time. (except
for sources and sinks) - Similarly, the number of vehicles entering the
back of the link equals the number exiting the
front.
74Simple Network
75Volume-Delay Functions
- Each link has a link volume delay function
relating travel time on that link and total flow
on the link. This is analogous to an average
cost curve used in economics.