EKONOMI PERKOTAANURBAN ECONOMIC TRANSPORTATION

KELOMPOK 5:

1. UMA ADI KUSUMA

2. NANIA TAMANA

3. AMALIA RAKHMAWATI

4. DWI LARASATI

5. SELENA DENNYSAL

One of the advantages of an urban location is its proximity to many activities within a metropolitan area. This part of the book examines the two main components of the urban transportation system.

Chapter 19 describe the automobile/ highway system, focusing on three problems caused by automobiles: congestion, pollution, and highway accidents.

Chapter 20 deals wiith urban mass transit, focusing on the choice of a commuting mode by a commuter (e.g., automobiles, bus, or light rail) and the choice of a transportation system by a city planner.

INSIDE THE CHAPTER

Autos and Highways

Congestion: Equilibrium vs Optimum Traffic Volume

Alternative to a Congestion Tax: Taxes on Auto Use

Highway Pricing and Traffic Volume in the Long Run

Congestion and Land-Use Patterns

Autos and Air Pollution

Examine three transportation problems caused by automobiles.

AUTOS AND HIGHWAYS

Congestion Air Pollution

Highway Accidents

Congestion during rush hours is inevitable, and a certain level of congestion is actually efficient. Just as it would be inefficient to eliminate all air pollution, it would be inefficient to eliminate all congestion.

The question is whether congestion is at optimum level. If not, there are a number of of policies that could decrease congestion.

First, including various taxes on auto travel, subsidies for mass transit, and highway construction.

The second problem, air pollution, is controlled by the federal goverment through its auto emissions policies.

The thrid transportation problem is auto safety. Traffic accidents injure and kill people, and also discrupt traffic flow, contributing to the congestion problem.

Centra

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Subu

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Modal Choice of Central-city and Suburban Commuters

WalkBus or railCarpoolDrive alone

CONGESTION: EQUILIBRIUM VS OPTIMUM TRAFFIC VOLUME Most cities suffer from traffic congestion during

the morning and evening rush hours. The annual cost of congestion (for extra time

and fuel consumption) in the 50 largest metropolitan areas is about $35 billion (Small, 1997).

We’ll use a simple model to explain the congestion phenomenon & evaluate some alternative public policies to deal with it.

Consider a city with the following characteristic:R

ad

ial h

igh

way

There is two-lane higway from suburbs to the city center (a distance of 10 miles).

Mon

eta

ry t

ravel

cost

Monetary travel cost of auto travel is 20 cents per mile.

Tim

e c

ost

The opportunity cost of travel time is 10 cents per minute.

The Demand for Urban Travel

The demand curve is a marginal-benefit curve. For each trafffic volume, it shows how much the marginal traveler is willing to pay for the highway trip.

Congestion Externalities and the Congestion Tax

The Private and Social Costs of Travel

A

Traffic voluame

(vehicles)

B

Trip time

(minutes)

CIncreas

e in Travel Time per

Driver(minute

s)

DIncrease in Total Travel Time

(minutes)

E

External Trip Cost

($)

F

Private Trip Cost($)

G

Social Trip Cost

($)

H

Marginal Benefit

(demand)

200 12.0 0 0 0 3.2 3.20 31.10

400 12.0 0 0 0 3.20 3.20 27.44

600 12.8 0.007 4.2 0.42 3.28 3.70 23.78

800 14.8 0.013 10.4 10.4 3.48 4.52 20.12

1000 18.0 0.019 19.0 1.90 3.80 5.70 16.46

1200 22.4 0.025 30.0 3.00 4.24 7.24 12.80

1400 28.0 0.031 43.4 4.34 4.80 9.14 9.14

1600 34.8 0.037 59.2 5.92 5.48 11.40 5.48

1800 42.8 0.043 77.4 7.74 6.28 14.02 182

2000 52.0 0.049 98.0 9.80 7.20 17.00

The relationships between traffic volume and travel time.Trip time = 12.0 + 0.001(volume - 400) + 0.000015(volume -400)2

Column B lists the trip time(the travel time per

driver).

Columns C&D show the effects of the

marginal driver on the travel times of other

drivers.

Column E are based on the assumption of

travel time is 10 cents per minute.

Columns F&G show the private and social

costs of travel.

The congestion externality: The marginal driver slows traffic and increases travel time, forcing other dreivers to spend more time on the road.

The external trip cost equal as the monetary value of the congestion externality.

The private trip cost is the travel cost incurred by the individual commuter, defined as the sum of the monetary cost($2.00) and the private time cost.

The social trip cost is the sum of the private trip cost(column F) and the external trip cost(column E).

Equilibrium number of drivers is a driver uses the highway if the marginal benefit of a trip(from demand curve) exceeds the private trip cost.

Optimum number of driver optimum level is the marginal benefit equals the marginal cost(basic efficiency rule).

Equilibrium vs Optimum Traffic Volume

The government could use a congestion tax to generate the optimum traffic volume.

A tax equal to the external trip cost would internalize the congestion externality, generating the optimum number of drivers.

The Policy Response: Congestion Tax

A key consideration in the evaluation of the congestion tax is the disposition of the revenue it generates.

The government doesn’t throw the tax revenue away, but presumably use it to finance public services or to decrease other local taxes.

To simplify the matters, suppose that the government redestributes the tax revenue, in equal shares, to all of the households who use the highway before the congestion tax is imposed.

Benefits and Costs of Congestion Taxes

A more rigorous analysis of the benefits and costs would show that some people in the city would be harmed by the congestion tax policy: for some travelers, the savings in the travel costs and the transfer payment would not be large enough to offset the congestion tax or the loss in consumer surplus.

And would also show that: the winners’ benefits exceed the losers’ costs.

Peak vs Off-Peak Travel

Congestion Tax during Peak and Off-Peak Periods

During the of-peak period, the demand for travel is relatively low, generating a low traffic volume (Vo, compared to Vp during the period), so the optimum congestion tax is relatively low

The government collect the congestion tax with: The high technology version of toll booths: a

vehicle-identification system (VIS). Under the VIS, every car is eqquiped with a

transponder – an electronic device that allows sensors along the road to idnetify the car as it passes.

The system records trhe number of times a vehicle uses the congested highway and sends a congestion bill to the driver at the end of the month

Implementing the Congestion Tax

A number of alternatif policies have been proposed. A set of policies may discourage auto use by the cost of auto travel.

ALTERNATIVE TO A CONGESTION TAX: TAXES ON AUTO USE

Gasoline taxes

Parking taxes

Congestion-zone taxes

How effective are these policies compared to a congestion tax?

The ways how congestion tax decreases the trafic volume

Modal substitution Time of travel

Travel route Location choices

Tax increases the cost of auto travel relative to carpooling and mass transit, causing some travelers to switch to those other modes.

The tax is highest during the peak travel periods, causing some travelers to travel at different times.

The tax is highest on the most congested routes, causing some travelers to switch to alternative routes.

The tax increases the unit cost of travel (travel cost per mile), causing some commuters to decrease their commuting distances.

One alternative to the congestion tax is gasoline tax. The simple idea is that if travel is more expensive, traffic volume decreases.

The problem is that the gas tax increases the cost of all automobile travel, not just travel along congested routes during peak periods.

In contrast with the congestion tax, which changes travel times and routes, gas tax doesn’t encourage drivers to switch to other travel times or routes.

Gasoline tax

A number of cities use parking taxes to discourage driving to central business district jobs.

Explained by Parody (1984), the surcharge decreased traffic volume because:

Parking tax

Some commuters switched to carpools and mass transit.

Some changed their travel times.

There are three potential problems with using parking taxes to decrease congestion.• Taxes must be imposed only on peak-

period commuters.1

• In contrast with congestion tax, parking tax doesn’t depend on the distance traveled.

2

• Because much of the congestion problem is caused by cars that do not park in congested areas, the tax doesn’t force all peak-period traveler to pay for the congestion they cause.

3

So far, congestion policies discuss about how to decrease congestion by increasing the cost of driving.

There are several alternative approaches.

Capacity Expansion and Traffic Design Subsidies for Transit

One response to the congestion problem is to widen the highway to increase its carrying capacity.

Widening the highway decreases the trip cost of all drivers, so it increases consumer surplus.

The city could also improve the flow of traffic on the existing highway, such as synchronized the street lights to keep traffic flowing at a steady speed.

Capacity Expansion and Traffic Design

Effects of Widening the Highway

The widening of the highway shifts the private trip cost to the right. The congestion threshold increases, and trip cost is lower at every traffic volume above the original threshold volume. The decrease in trip cost increase traffic volume. The benefit of widening is increasing in consumer surplus.

Another alternative to the taxation of auto travel is the subsidization of mass transit. Because transit and autos are substitute travel modes, so a decrease in the cost of transit causes some consumers to switch from autos to transit.

In other words, a transit subsidy decreases the auto volume, narrowing the gap between the equilibrium and optimum traffic volume.

Subsidies for Transit

Effects of Transit Subsidies on Auto Volume and Transit Ridership

In the optimum situation, auto drivers pay a congestion tax, so auto volume is A* and transit ridership is T*. If there is no congestion tax, the auto volume is A’ and transit ridership is T’. A transit subsidy increases transit ridership to T” and decreases auto volume to A”.

HIGHWAY PRICING AND TRAFFIC VOLUME IN THE LONG RUN

• Derive the average total-cost curves for different highway widths.

• Derive the long run cost curves (average and marginal).

• Pick the optimum traffic volume and road width.

• Pick the congestion tax that generates the optimum traffic volume on the optimum road.

Derive The Average Total-cost Curves for Different Highway Widths

ATC = Trip Cost + Average Road Cost

Total cost of building highway devide number of trip

Two effects on ATC caused by an incerasing traffic volume:The roads-cost effect & The trip-cost effect

The ATC reaches its minimum point at a volume of V’ and V* drivers

Under assumption of constant return to scale in highway building

Long-Run Average Cost and Marginal-Cost Curves

• LRAC shows the minimum average total cost for each traffic volume

• Two points on LRAC: V’ drivers on C* (2 lanes) & V* drivers on C* (4 lanes)

• Made up of the minimum point of ATC for different width, optimum highway for each traffic volume

• Given the assumption of constant return to scale, LRAC= horizontal

LRMC indicates the marginal social cost of an additional driver, including the cost widening

LRMC is the as LRAC

Optimum Volume and Road Width

Optimum Traffic Volume:MB = MC

D AC

V* as the optimum traffic volume

4 lanes as the optimum road width

How does city persuade the optimum number of drivers to use the highway?

Depend on the existention of congestion tax

Congestion Tolls Pay for the optimum Road

The revenue from the congestion tax covers the cost of bulding the road.

If tax revenue exceeds the total cost of building the road, the roads should be widened.

Untuk mengetahui efek dari eksternalitas kepadatan dan pajak kepadatan pada pola penggunaan lahan .

Dengan menggunakan konsep Land Rent dan Urban Land Use patterns untuk menjelaskan bagaimana sistem pajak kepadatan merubah penggunaan lahan dan ukuran kota.

CONGESTION AND LAND-USE PATTERNS

Partial Equilibrium Effects

Peningkatan unit cost of commuting meningkatkan slope housing price function dan residential bid-rent function

Partial-Equilibrium Effects of Congestion Taxes

Congestion Taxes and Residential Density

Menjelaskan efek perubahan lahan terhadap pasar tenaga kerja kota.

Pajak meningkatkan total penawaran tenaga kerja karena meningkatkan efisiensi sistem transportasi kota dan meningkatkan kesejahteraan resident kota.

Karena pajak kepadatan menghasilkan keuntungan untuk city resident, maka aktivitas relatif kota juga meningkat, dan kemudian meningkatkan total penawaran tenaga kerja.

General Equilibrium Effects

Pajak kepadatan juga meningkatkan tingkat upah kota, karena peningkatan total penawaran tenaga kerja yang menyebabkan excess penawaran tenaga kerja.

Untuk mengetahui bagaimana perubahan kota setelah adanya general equilibrium effects, bisa dengan menggunakan komputer untuk memperoleh 2 gambaran keadaan ekonomi sebelum dan sesudah pajak.

Variable Initial CityCongestion Tax

City

Population $18000 $61000

Wage ($ per hour) 6.00 5.31

Commute distance (miles) 3.72 3.42

Commuting Time (hours/week) 3.73 3.41

Percent of Land use for transportation 17.9 16.2

General Equilibrium Effects on Congestion Taxes

Analisa congestion tax menjelaskan tentang pentingnya peraturan untuk masalah urban.

Kota yang memberlakukan pajak kongesti biasanya akan tumbuh.

Hal tersebut dikarenakan pajak kongesti meningkatkan efisiensi transportasi kota dan meningkatkan keatraktifan relatif kota tersebut.

Another urban transportation problem is air pollution resulting from the emissions of motor vehicles. In the US, Motor vehicles powerd by petroleum products emit carbon dioxide (CO2), one of the “greenhouse” gates that are accumulating in the atmosphere.

Most scientists believe the buildup of these gases will cause global temperatures to increase, resulting in significant changes in weather patterns.

AUTOS AND AIR POLLUTION

Amendements to the Clean Air Act (in 1977 and 1990) included one innovative feature for the control of stationary pollution source. In cities where EPA standards were exceeded, new pollution source were allowed if two conditions were stasified.

First, the new sources had to adopt the most effective abatement technology. Second, existing source had to dercrease their emissions to ensure that there was a net improvement in air quality.

The economic approach to air pollution starts with a description of the externality problem. Drivers base their travel decisions on the marginal private cost of driving, which is less than the marginal social. cost because autos and trucks cause air pollution. The pollution externality by causes people:

1. To drive cars that generate a relatively large amount of pollution per mile driven and

2. To drive many too miles. To an economist, the obvious response is to force people to pay for pollution, that is to internalize the externality.

The Economic Approach: Effluent Fees

One approach would be to install amonitoring device in every car. Such a device woulde be measure the car’s emissions, allowing the goverment to tax the car owner for the air pollution caused by the car.

For example, if the estimated pollution cost per unit of carbon monoxide is one cent, the monthly bill would $2 for a vehicle that emits 200 units permonth, and $3 for a vehicle that emits 300units.

An alternative approach for controling auto pollution is to subsidize mass transit. Although both autos and mass transit generate air pollution, the pollution per passenger is lower on mass transit. If there are no pollution taxes, auto travel is underpriced relative to transit.

As explained earlier in the case of congestion externalities, the underpricing of autos generates an excessive traffic volume (the equlibrium auto volume exceeds the optimum volume) and too little transit ridership (the equilibrium transit ridership is less the optimum ridership).

Transit Subsidies

One response to the underpricing of autos is to sibsidize transit , the subtstitue good.

T H A N K Y O U