Access in Appalachia

A Primer for Measurement and Decision-Making
Acknowledgements

Appalachia Regional Commission

The Appalachian Regional Commission (ARC) provided funding, leadership, and project 

management for the project. ARC is an economic development agency of the federal 

government and 13 state governments focusing on 420 counties across the Appalachian 

Region. ARC’s mission is to innovate, partner, and invest to build community capacity and 

strengthen economic growth in Appalachia to help the Region achieve socioeconomic parity 

with the nation. Ryan Brumfield, Senior Transportation Advisor, served as the Project Director.

Report Authors

Mark Sieber, Naomi Stein, Glen Weisbrod, Ralph Straumann, and Adam Blair

EBP US, Inc., formerly Economic Development Research Group, Inc. 

Research Report Reference

This primer is derived from the research report “Access in Appalachia” developed by ARC, 

together with EBP (formerly EDR Group), as a methodological framework for accessibility 

measurement specifically for the needs and purposes of the Appalachian Region. The report 

can be downloaded from www.arc.gov

Contents

PRIMER PURPOSE AND AUDIENCE .....................................................................................1

OVERVIEW .......................................................................................................................3

ACCESS AND ECONOMIC OPPORTUNITY ...........................................................................10

ACCESSIBILITY MEASUREMENT IN DECISION MAKING ........................................................13

A FRAMEWORK FOR MEASUREMENT ................................................................................16

DEVELOPING ACCESSIBILITY METRICS .............................................................................19

MOVING FORWARD .........................................................................................................24

REFERENCES .................................................................................................................25
Access in Appalachia: A Primer for Measurement and Decision-Making 1

Primer Purpose and Audience

Primer Purpose and Audience

Why Consider Access in Transportation Planning?

Why Consider Accessibility? The field of transportation planning has been evolving in recent 

years, with growing recognition of the importance of “accessibility” as a central objective and 

performance measure. Accessibility refers to the ability of people to reach desired destinations 

and activities (or conversely, the ability of business activities to reach workers and customers). 

This is the fundamental reason why transportation infrastructure and services exist, yet the 

concept had until recently been difficult for many transportation agencies to measure. While 

measuring travel times and costs is still a major part of benefit evaluation, agencies today can 

now make use of new datasets and tools to measure and monitor levels of accessibility in their 

jurisdiction and utilize this information to make more effective investment decisions. This 

document shows how.

The need to measure and improve accessibility is particularly important for regions of the United 

States, including Appalachian States, where there are constraints on accessibility and 

challenges for economic development due to topographic, service availability, and spatial 

factors. The Appalachian Regional Commission was established in part to help address the 

Region’s isolation and accessibility limitations, and since its founding has worked with its 

partners across the region to improve access and economic opportunity. The primary goal of the 

Appalachian Development Highway System (ADHS) is to help reduce isolation and better 

connect residents of the Appalachian Region to broader markets. Although the ADHS is now 

nearly 90% complete, many parts of Appalachia still suffer from isolation and poor access.

Thus, it becomes important for state and regional agencies to take further action to improve 

accessibility to jobs, health care, and education for their residents.

Primer Purpose. This primer is designed to:

• Provide a simple overview of what access is and why it matters

• Highlight the link between access and social and economic opportunity

• Outline the types of access that are most relevant in Appalachia

• Provide guidance to effectively incorporate accessibility in transportation decisionmaking by making use of available information sources and analysis methods.

Audience. This primer is intended for use by transportation and economic development 

professionals in state, regional, and local government. Those who have never explored 

accessibility concepts and measurement approaches will find guidance on where to start. More 

seasoned analysts can use this primer to understand how accessibility analysis can extend 

beyond the traditional focus of access to jobs to other types of access, and to learn about 

special consideration for accessibility in rural areas. This primer is particularly appropriate for 

those tasked with directing transportation investments based on assessments of needs and 

opportunities.
Access in Appalachia: A Primer for Measurement and Decision-Making 2

Primer Purpose and Audience

Structure. The primer is structured to mirror the process for building accessibility considerations 

into decision-making, as shown in Figure 1. It starts with an overview to give readers an 

understanding of accessibility concepts. The second chapter focuses on the goals of 

accessibility measurement, namely support for economic development. The third chapter 

situates accessibility within the decision-making process, to help readers determine the scope of 

their analysis. The fourth chapter dives into different definitions of accessibility that can be 

employed to address the needs of businesses and people. The fifth chapter focuses on the 

process for assembling data and analytical resources to implement selected measures. Finally, 

the last chapter addresses opportunities to create change and how ARC and its partners can 

move forward together.

FIGURE 1 SIX STEPS TO BUILD ACCESSIBILITY CONSIDERATIONS INTO DECISION-MAKING
Access in Appalachia: A Primer for Measurement and Decision-Making 3

Overview

Overview

What Is Accessibility?

A Focus on Opportunities

Definitions. Accessibility refers to the ability of people and businesses to reach activities, 

services, and goods given available transportation options. It is a way of quantifying how many 

activities are reachable within a given level of effort. For example, in Figure 2, one could count 

how many customers a company can reach within a three-hour drive of a location in Bristol, 

Virginia.

Accessibility addresses not only where people or goods currently travel, but the potential or 

opportunity for interaction, based on where they could travel.1 Accessibility levels depend on (1) 

how many destinations are within a certain area and (2) a person’s (or shipment’s) level of 

mobility, or ability to travel between places.2 Passenger transportation provides access to 

activities that people value, including work, shopping, recreation, health care, and education. 

Freight transportation ensures that households can purchase goods and provides businesses 

with the ability to ship and receive supplies and finished products. Each of these destination 

types represents a form of economic or social participation. In places with low-density 

settlement patterns like Appalachia, accessibility can be particularly dependent on levels of 

mobility, given the distances between relevant activities.

FIGURE 2 EXAMPLE–AREAS ACCESSIBLE BY DRIVING WITHIN 40 MINUTES AND 3 HOURS OF BRISTOL, VA

Source: Produced by EDR Group (now EBP) using Esri Business Analyst Online.

Access and economic development. Accessibility is essential for economic development. 

Businesses of all types rely on the transportation system to access workers, inputs, markets, and 

collaborators. Places reliant on manufacturing or resource extraction tend to be proportionally more 
Access in Appalachia: A Primer for Measurement and Decision-Making 4

Overview

concerned with freight access to supplier and customer markets via transportation connections. 

Places that are service-oriented, on the other hand, have proportionally greater requirements for 

access to skilled workers, broadband, and educational institutions.

Accessibility improvements can generate economic development by attracting new businesses to a 

region or increasing the productivity of existing businesses. When businesses decide where to open 

new locations or relocate, many list accessibility factors among their top criteria.3 Through increased 

market access, firms can increase their sales and use capital and labor more efficiently. The term 

“agglomeration economies” refers to the business productivity benefits associated with industry 

clustering and improved access to workers, suppliers, and customers. These economic forces tend 

to encourage spatial clustering at various geographic scales and lead to firms being more productive 

when they have better access.

4

Accessibility is also necessary for ameliorating economic distress. The World Bank considers 

“access for all to economic and social opportunities” as central to their mission of reducing 

poverty and improving health and human development outcomes.5

Challenges in Appalachia. Remote areas like those throughout Appalachia tend to be poorly 

served by freight and transit operators due to lower demand. Because of the effects of poverty and 

aging in Appalachia, specific accessibility challenges arise for people who lack access to a personal 

automobile and therefore have difficulty reaching jobs, school, or other destinations. Some areas 

also have limited roadway network coverage because of high construction costs associated with 

topographical barriers like mountains or rivers, coupled with less dense settlement patterns and 

other spatial constraints.6 Each of these challenges can make access in rural areas a major 

impediment to people’s well-being and businesses’ economic viability.

Recognizing both the opportunities associated with good access and the considerable 

challenges derived from constrained access, access measurement is a way to better 

understanding opportunities, pinpointing problem areas, and providing a platform for action.

Three Dimensions of Measurement

Accessibility measures typically address three dimensions as shown in Figure 3: (1) the user 

group, defining the perspective of the measure, (2) the attractions, destinations, or opportunities 

to which access is being considered, and (3) network availability and performance, which 

dictates whether trips are possible by a given mode and how easy or hard the connection is.

FIGURE 3 THREE DIMENSIONS OF ACCESSIBILITY DEFINITION

Table 1 describes at a high level the options available for each of these dimensions, along with 

guidance and special considerations for rural areas. Because access measures always assess 

opportunities that are accessible from a given location, the user group options represent 

User Group

Access for whom/from 

where?

Attractions/Destinations

Access to where/what?

How well does the 

destination meet the need?

Network Availability and 

Performance

Can you get there? How easy 

or hard is it?
Access in Appalachia: A Primer for Measurement and Decision-Making 5

Overview

different choices on how to select that starting point when conducting an analysis of access 

across a region. The options for attractions/destinations address the question of how to 

represent the number and importance of accessible opportunities. Finally, the network 

availability and performance options relate to which attributes of transportation system 

performance and which networks should be considered when trying to determine the relative 

ease or difficulty of accessing a given opportunity. Not included in this table is guidance on how 

to determine which opportunities are “counted” as accessible—i.e., how travel 

time/distance/cost mediate the value of accessible opportunities. This is addressed through the 

functional form of an accessibility measure, which is discussed in the next section.

TABLE 1 OPTIONS AND CONSIDERATIONS FOR DEFINING AN ACCESSIBILITY MEASURE 

Options Considerations and guidance

User Group

Measure access for users based on 

analysis of access:

▪ From all centroids within a zonal 

system

▪ From all cells in a standard grid

▪ From key locations (e.g., major 

employment centers)

▪ For all zones or cells, but weighted by 

the number of users affected

▪ Using standard geographic units (e.g., from 

the Census) can help with reproducible 

comparisons across different areas

▪ Consider weighting accessibility scores by

affected users, particularly in sparsely 

developed rural areas

▪ Consider also weighting scores by 

measures of economic disadvantage (to 

focus on equity)

Attractions / 

Destinations

▪ Counting discrete opportunities (e.g.,

number of schools)

▪ Defining hierarchies of importance by 

granting a greater number of points to 

activities of a certain kind, quality, or 

scale (e.g., more points for a level I 

trauma center than levels II–IV).

▪ Counting using indicators of magnitude 

(e.g., population or employment).

▪ Prioritize destinations based on a hierarchy 

of needs, guided by planning goals or 

stakeholder input

▪ Given the sparseness of the transportation 

network in some parts of Appalachia, 

measures that focus on network rather than 

activity access (e.g., access to rail 

terminals, ports) may also be appropriate.

Network Availability & 

Performance

Units of “impedance:”

▪ Travel distance

▪ Travel time

▪ Travel cost

Network definitions:

▪ By mode (e.g., drive, transit, walk, 

bike)

▪ Time of day

▪ Truck restrictions/routes

▪ Travel time is the most commonly used 

“impedance” measure as it both conveys 

outcomes of transportation network 

performance from a user’s perspective and 

is easy to interpret

▪ Given the significant challenges faced by 

those without private vehicles, consider 

analyzing non-car accessibility

▪ Depending on the focus of analysis, other 

units of “impedance,” such as generalized 

cost or special network definitions (i.e.,

truck networks), may merit consideration
Access in Appalachia: A Primer for Measurement and Decision-Making 6

Overview

Source: ARC

Common Measurement Forms

Accessibility measures are designed to reflect the fact that destinations that take more time to 

access are, all else equal, less desirable or useful than those located close by. Moreover, at 

some point travel times become unreasonable and a destination should be considered 

effectively inaccessible. The manner in which this underlying logic is incorporated into 

accessibility measures varies and falls into two primary categories:

• Contour measures. These include all activity reachable within a given travel time threshold.

• Potential/gravity measures. These sum all activities in an area of analysis, weighted such that 

opportunities that take more time to access are granted less weight than those close to the 

point of origin.

There are also approaches where measures only address access to the nearest destination. 

This implies either that access to additional destinations after the first one is not meaningfully 

better and/or that the purpose of the analysis is address a basic form of minimal access or 

sufficiency. Intermodal connectivity is often treated this way (i.e., access to the closest airport). 

In this situation, there are a few distinct measurement options:

• Measuring travel time to closest opportunity.
Access in Appalachia: A Primer for Measurement and Decision-Making 7

Overview

• Constructing a measure of the general form where 

Access = (Measure of the importance of the destination) / (Travel time). For example, one 

might measure volume at the port as a proxy for its relative importance.

• Binary sufficiency measures. i.e., a yes or no as to whether at least one destination is 

accessible within a defined threshold.

Figure 4 illustrates how these different functional forms of accessibility measures would treat the 

same spatial configuration of users and destinations. Note that these diagrams are presented in 

terms of straight-line distance (meaning thresholds appear as circles) but actual measures 

would use travel time and therefore not have perfectly circular boundaries.

In the case of the contour measure, only the two destinations within the threshold matter. They 

also “count” at the exact same level of importance even though one is considerably close. The 

diagram also highlights the somewhat arbitrary nature of threshold selection. The third closest 

destination lies just outside the boundary but is treated as providing no value, compared to the 

one just inside the threshold. On the other hand, the potential/gravity type measure instead 

recognizes all the destinations along a continuum of importance based on how far away they 

are. Finally, the nearest destination/sufficiency type measures only recognize the one closest 

destination, with all others treated as irrelevant.

FIGURE 4 ILLUSTRATION OF DIFFERENT FUNCTIONAL FORMS OF ACCESSIBILITY MEASURES
Access in Appalachia: A Primer for Measurement and Decision-Making 8

Overview

Source: ARC

Table 2 presents some of the pros and cons of contour versus potential/gravity measures. They 

each have strengths and weaknesses for different audiences and applications.

TABLE 2 PROS AND CONS OF CONTOUR V. POTENTIAL/GRAVITY MEASURES7

Pros Cons

Contour

▪ Easier to interpret, communicate, 

calculate

▪ May be more attractive to general 

users/high-level decision makers

▪ Thresholds are inherently arbitrary 

▪ No differentiation of opportunities within 

isochrone

▪ Can be very sensitive to travel time 

changes, which can make it harder to use 

in evaluating changes

Potential/

Gravity

▪ Addresses many of the theoretical 

issues of contour measures

▪ May be more attractive to researchers 

interested in detailed comparisons

▪ Harder to interpret/communicate

▪ Requires selection of a specific decay 

function
Access in Appalachia: A Primer for Measurement and Decision-Making 9

Overview

Selecting Thresholds or Distance Decay Functions

Thresholds or parameters of spatial decay functions are typically chosen to reflect travel behavior. 

In practice, this can mean either (a) selecting “rule of thumb” thresholds (e.g., 60 minutes), or (b) 

selecting thresholds or parameterizing decay functions through analysis of empirical data on 

spatial travel behavior. The latter approach relies on data describing the distribution of trip 

durations, stratified by variables of interest—namely trip purpose, mode, and location/area type. 

The National Household Travel Survey (2017) offers a recently updated national data set of this 

type, but individual regions and states may have their own data from custom surveys.

Negative Exponential Functions: Spotlight Example

For potential/gravity measures, the most common functional form is a negative exponential 

function of the form:

Ai = ∑Dje

−βtij

n

j=1

Where Ai is the accessibility of zone i to all destinations in other zones (j) and tij is the travel 

time between zone i and zone j. Dj is a measure of the importance of destinations in zone j. 

Here β determines the shape of the decay function that mediates the opportunity offered by 

the destinations. Where travel time is zero, e

−βtij = 1, meaning the full measure of the 

importance of the destination is counted. For any travel time greater than 1, that factor 

becomes a fraction reducing the weight given to the destination opportunity. One approach to 

choosing the parameter β is to find the 95th percentile of travel time for a mode/trip 

purpose/region type of interest and then set β such that if tij=t95, then e

−βtij = 0.05. For the 

sake of illustration, if travel data shows that 95% of school trips are less than 55 minutes in 

duration. This would mean a β of approximately 0.054 calculated as described previously and 

would yield a decay function of the shape shown in Figure 5.

FIGURE 5 ILLUSTRATION OF NEGATIVE EXPONENTIAL FUNCTION

55, 0.05

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55

0.60

0.65

0.70

0.75

0.80

0.85

0.90

0.95

1.00

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75

Decay Factor

Travel Time
Access in Appalachia: A Primer for Measurement and Decision-Making 10

Access and Economic Opportunity

Access and Economic 

Opportunity

How Does Accessibility Support Economic 

Opportunity?

Access Needs

Accessibility is about connecting people and businesses to the activities and resources they 

need to participate fully in the economy and society. The following table summarizes key types 

of access, as identified from research literature on economic development and opportunity.

People and Businesses Need Access To...

Jobs and Workers–Labor Market Access

Businesses are more productive when they have access to broader labor markets 

as this enables better matching between their requirements and the skills of 

available workers.8 This is proportionally more important for service or knowledgebased industries, but workforce is, in fact, one of the top site selection criteria 

across all industries.9 Accessibility is also key to ensuring people can access and 

maintain gainful employment. In places with high unemployment, improving access 

can increase the number of job opportunities available to residents.10

Customers, Suppliers–Access to Goods and Services

Businesses also need access to their customer base, whether that’s individual 

consumers or other companies to which they provide goods and services. 

Conversely, businesses are also dependent on transportation for access to 

suppliers, whether of material goods or of services that require in-person support.

Transportation access can dictate the effective service area of businesses, defined 

either by people’s willingness to travel, or by the performance of freight 

transportation networks in supply chains. Customer access can range from very 

local (e.g., for a convenience store) to highly global (e.g., for a specialized 

manufacturer). Nevertheless, research shows that same-day truck delivery markets 

are particularly important indicators of competitiveness.11 Finally, providing access 

to consumer goods and services is a fundamental purpose of transportation and 

can make a community more attractive.

Network Access - Intermodal Terminals and Key Nodes

Connectivity to long-distance transportation networks (airports, marine ports, 

intermodal rail) broadens the geography of market access, particularly in a 

globalized economy and may be considered as its own dimension of access as 

well. For example, in Amazon’s highly publicized request for proposals for a second 

headquarters, the company defined a set of minimal transportation access 
Access in Appalachia: A Primer for Measurement and Decision-Making 11

Access and Economic Opportunity

requirements including “Proximity to major highways and arterial roads” within 1–2 

miles and “Proximity to International Airport” within approximately 45 minutes.12

Access to Education

Economic development may be hindered where potential students do not have 

good access to colleges and other schools and where employers do not have 

access to an adequately educated workforce. While 42% of the nation’s young 

people between age 18 and 24 are enrolled in a higher education institution, only 

29% of rural people are.13 While there are other individual and social barriers to 

higher education, research shows that distance to college also correlates with 

students’ choices to apply or enroll. This is the case even more so in rural areas, 

since lower socioeconomic status is more common in rural areas and substantial 

savings can be achieved when college students are able to live at home.14 For 

many rural people, community colleges provide the only accessible opportunity for 

higher education. About two-thirds of public two-year colleges serve rural 

communities, providing a critical path to careers and four-year universities.15

Research has shown that rural counties with an established community college or 

university have experienced greater job growth over time than counties without 

institutions of higher education.16

Healthcare Access

The ability to access medical care is critical to the overall health and welfare of 

society. This is especially true for vulnerable rural populations, including older 

adults, people with disabilities, low-income individuals and families, and veterans or 

those who otherwise have unique healthcare needs.17 Lack of accessibility to care 

can lead to delayed or missed appointments, disruption to care for chronic 

conditions, increase in stress for patients, and decline in use of some medication.18

Approximately 3.6 million Americans miss or delay non-emergency medical care 

each year because of transportation-related issues.19 Older adults tend to have 

lower mobility levels, which negatively affects their ability to access health facilities 

and services.20 Vehicle availability is also consistently associated with increased 

access to health care.21 Out of the 420 counties in the Appalachian Region, 149 

rank in the worst national quintile regarding years of potential life lost (YPLL).22

Transportation is one of three main barriers to health care for rural populations.

23

Opioid addiction is considered a public health epidemic in the United States and 

especially in some Appalachian states. Opioid deaths and injuries have increased 

the most in rural areas where emergency medical response times are longer. In 

addition, opioid addicts living in rural areas face greater barriers to treatment given 

a lack of public transportation and longer travel distances relative to urban areas.24

Broadband Availability and Access

In an increasingly networked economy, broadband connectivity is critically 

important to the business community, contributing to increased productivity, 

competitiveness, and efficiency.25 Access to broadband internet is also increasingly 

being recognized as a prerequisite for people’s access to various other services, 

such as health care, education, employment.26 While only 7% of the United States’

population does not have broadband access in their neighborhoods (25 Mbps 

download or faster), in rural America this share is 27.4%.27 Where educational 

institutions, health care providers, and employers are not sufficiently accessible to 

people, broadband access can serve as a partial substitute for physical access.
Access in Appalachia: A Primer for Measurement and Decision-Making 12

Access and Economic Opportunity

Transportation Barriers to Access

While accessibility is a product of both the spatial pattern of available activities and the 

transportation system, there are cases where transportation creates a barrier to access. The 

most commonly cited transportation access barriers are described below. 

Transportation Barriers to Access

Vehicle Availability / Ability to Drive

Even though driving is the predominant mode for most people in Appalachia, 

those without vehicle access or who cannot or choose not to drive face 

particularly harsh barriers to access in rural areas where transit service is 

sparse or non-existent and where distances to desired destinations are 

considerably longer. This barrier is exacerbated by poverty and the aging 

population of many rural communities.

Network Coverage

Some areas have limited roadway or rail network coverage because of high 

construction costs associated with topographical barriers like mountains or 

rivers, coupled with less dense settlement patterns and other spatial 

constraints.28

Service Availability and Scheduling

Remote areas like those throughout Appalachia tend to be poorly served by 

freight and transit operators due to low demand. When service is available, 

schedules may be inconvenient and create significant schedule coordination 

burdens.

Geometry

The physical design of a roadway can constrain the ability of larger trucks to 

pass. Relevant dimensions include road width, clearance, turning radius, 

weight limits, and the existence of passing lanes or shoulders. Similarly, 

some rail routes may lack the vertical clearance for double-stacked container 

movements.

Congestion

Particularly in the vicinity of more urbanized areas and major terminals, 

congestion can constrain mobility. Delay and unreliability associated with 

congestion reduce the number of activities that can be reliably reached within

a given time and cost and thus reduce the level of access provided by the 

transportation system.
Access in Appalachia: A Primer for Measurement and Decision-Making 13

Accessibility Measurement in Decision Making

Accessibility Measurement in 

Decision Making

How Can Accessibility Measurement Help?

The Planning Process

Accessibility concepts and measures can be integrated into all phases of the transportation 

planning process as shown in Figure 6. 

FIGURE 6 ACCESS IN PERFORMANCE-BASED PLANNING AND PROGRAMMING

Before pursuing any form of analysis, or evaluation it is important to start at the visioning step. 

Here, an agency should define how accessibility fits into its mission. Accessibility can be 

integrated into the goals and objectives established for an entire agency or plan, or it may be 

the focus of a specific program. For example, some state departments of transportation fund 

economic development access programs that provide funds for building connections to new 

development sites or community resources.29 Acknowledging access as an explicit goal or 

objective helps communicate the intention of subsequent planning and motivates the use of 

access measures to guide decision-making.

Subsequently, within the planning process, access measures can be used in assessment and 

diagnosis to determine how access varies across regions or modes and to identify constraints 

that may need to be addressed through transportation improvements. Accessibility analysis can 

•Integrating accessibility into agency or program goals and objectives

Visioning

•Assessment: How does access vary across regions or modes?

•Diagnosis: Where are there constraints that should be addressed?

Planning

•Project evaluation and prioritization

•Directing resources towards improving access

Programming

•Monitoring the effects of improvements

•Tracking changes in accessibility over time

Performance Monitoring
Access in Appalachia: A Primer for Measurement and Decision-Making 14

Accessibility Measurement in Decision Making

be integrated into state and metropolitan planning organization (MPO) long-range plans in the 

context of evaluating current or forecasted future needs. Developing data and maps highlighting 

areas with lower levels of access can support the targeting of investments both by those 

developing the plans and by local planning partners.

Moving from broad diagnostics to developing programs of projects, access measures can serve 

as criteria for project evaluation and prioritization. In this context projects can be scored based 

on (1) the level of existing accessibility constraint in the areas served, (2) the degree to which 

the proposed project would ameliorate that deficiency, or (3) some combination of the above. 

Scoring can be based on quantitative access measures or may involve qualitative scoring (e.g., 

from 1 to 5) based on the judgement of planners with local knowledge. Incorporating 

accessibility criteria into prioritization helps decision-makers direct resources towards their goal 

of improving access in a way that is transparent and consistent across projects.

Finally, access measures may be incorporated into performance monitoring to track changes 

over time, including monitoring the effects of project improvements. This is perhaps the least 

developed area of access measurement but represents an opportunity as states and regions

more fully implement federal guidance on performance-based planning and programming.

30 To 

build accessibility into performance monitoring requires measurement approaches that use data 

that is cyclically and consistently updated over time. While federal sources such as the U.S. 

Census Bureau provide this for many forms of activity data, transportation network performance 

data is more varied in its availability and how frequently it is updated. Data availability is 

discussed more fully in the section that starts on page 16 of this primer.

Source: ARC 
Access in Appalachia: A Primer for Measurement and Decision-Making 15

Accessibility Measurement in Decision Making

Comparative Analyses

Accessibility measures, like many performance measures, 

are most useful for decision support when interpreted 

comparatively. This can include:

• Comparing across places to identify locations that 

face access disadvantages. For example, one 

might choose to focus specifically on areas within 

the bottom 10% of accessibility scores.

• Comparing relative to benchmark or standard of acceptable access. For example, a 

2002 directive from the Ministries of Health Services and Health Planning in British 

Columbia, Canada, sets minimum requirements for access to acute health care,

including “Access will be provided to emergency services on a 24/7/52 basis within a 

one hour travel time for 98% of residents within the region.”31

• Comparing accessibility with and without a project. To make a comparison, an 

analyst must use forecasting tools to estimate changes in travel time or cost from a 

transportation project and calculate the accessibility metric in both the base and build 

cases.

• Comparing among projects. Particularly for prioritization, projects can be ranked 

according to their accessibility or their accessibility improvement scores. Alternately,

accessibility scores may be integrated into a weighted multicriteria evaluation framework 

where projects are ranked according to composite performance across many categories. 

• Comparing over time. As describe above, this supports performance management and 

tracking of how well transportation agencies are meeting their goals.

• Comparing across user groups. Sometimes specific groups are disproportionately 

affected by access constraints. In this case it can be helpful to compare accessibility 

across user groups. For example, one might weight accessibility scores by measures of 

the number of people below the poverty level in that zone or by the proportion of 

households without cars. Alternately, an analyst might first select areas that fall below or 

above a certain threshold–i.e., a designated level representing high unemployment–and 

then compare accessibility scores for areas in that subgroup to accessibility for those 

that are not. 

Application

The application of access measurement to decision-making includes (1) a combining of spatial 

and transportation network data in an analysis to understand what is accessible from different 

points in a region. This information is then used (2) in a comparative fashion to rank levels of 

access across communities. Finally (3), when considering projects, this information can be used 

to give greater priority to projects that address current access deficiencies and are expected (or 

modeled) to yield access improvements. Within a planning process, steps 1 and 2 might happen 

in the context of a long-range plan or special study, while step 3 could occur in the context of 

programming projects.

COMPARE

▪ Across places

▪ Relative to a standard

▪ With and without a project

▪ Among projects

▪ Over time

▪ For different users
Access in Appalachia: A Primer for Measurement and Decision-Making 16

A Framework for Measurement

A Framework for Measurement

Focus on the Success of People and Businesses

Key Metrics

Both people and businesses rely on access. While businesses need access to labor, suppliers,

and markets to be economically successful, people need access for both economic and social 

well-being.

As people’s needs are not limited to work, destinations to be considered go far beyond potential 

employers. Education, health care, shopping, and recreation are also needs that people have

and should be addressed. Corresponding destinations should also be accessible and are of 

great importance for economic outcomes. Education provides qualification for a wider range of 

jobs with higher earnings; accessible health care supports people’s workforce participation and 

productivity; and recreational opportunities help people stay healthy, make communities more 

attractive, and can themselves be a driver of economic activity. 

Such a broad view of accessibility requires a wide range of accessibility metrics. As described in 

Figure 3, the user group and the destination are their main descriptors. In their combination, the 

user group may make a metric more specific by defining for whom the specific destination is 

important. Schools as a destination, for example, are most important for students under age 18.

Theoretically, a system of metrics based on all possible combinations of user groups and 

destinations, including the mode by which the destination can be reached, would give full 

flexibility to choose the metrics that seem most appropriate for the intended use. However, to 

focus analysis on what is most important, it is helpful to limit the number of metrics. Appalachia 

serves as the guiding principle for that step.

The following suggestion of key metrics is based on a literature review and on interviews within 

the Appalachian Region. The set of metrics is intended to cover major accessibility, businesses 

and people may have. Additional detail on the reasons behind these selections and the types of 

data that can be used to support these measures can be found in the full research report, 

Access in Appalachia: Concept and Methodologies, available on the ARC website. The report 

also lists complementary metrics that can add information and address individual agency needs. 
Access in Appalachia: A Primer for Measurement and Decision-Making 17

A Framework for Measurement

Access for Businesses

Businesses have three main access needs: for workers, supply chain, and delivery. Intermodal 

nodes may serve as destinations for both supply chain and delivery to extend the geographic 

reach of businesses. 

As destinations for specific businesses are unknown and can only be captured in the abstract, 

the spatial distribution of employment is suggested for use as a representation of potential 

suppliers, while the distribution of population may serve as the representation of potential 

consumers. 

TABLE 3 SUGGESTED KEY METRICS FOR BUSINESSES’ ACCESS

Business Specification Access to ... Destination Specification

All Labor Associate's or higher

Manufacturing

Supply chain Employment

All

Trade & Warehousing Delivery Consumers Population

Manufacturing and Trade & 

Warehousing Intermodal 

connectivity

a) Rail facility All freight rail facilities

b) Port Coastal port

All c) Airport All

Access for People

People’s needs to access places center on employment, education, health care, shopping, and 

recreation. While some of these destinations are important to everybody, employment and 

education are more important for certain age groups than for others. Defining the user group 

more specifically may help the metric to portray accessibility more accurately. Note that town 

centers were identified as a way to represent locations where retail and other services tend to 

be concentrated in rural areas.

TABLE 4: SUGGESTED KEY METRICS FOR PEOPLE’S ACCESS

Population 

Specification

Access to ... Destination specification

Age 18–65 Job Employment

Age 18–24 Education College All

All Health care 

a) Primary care General practice

b) Trauma center All

c) Addiction treatment center All substance abuse

All Town centers All

All Tourist destination National and State Designated
Access in Appalachia: A Primer for Measurement and Decision-Making 18

A Framework for Measurement

Broadband Access

Broadband internet can assist in bridging gaps where physical accessibility is insufficient for any 

or all groups of the population. To work from home, to attend online educational programs, or to 

use telehealth services may make a place with poor physical access more livable. However, 

each of these requires broadband internet of a sufficient speed/quality. 

TABLE 5: SUGGESTED KEY METRICS FOR BROADBAND ACCESS

Access to ... Sufficient Speed/Technology

Mobile Broadband (i.e., cell phones) LTE

Fixed Broadband (i.e., at home) ≥ 25/3 Mbps download/upload

Multimodal Accessibility

As described above, various user groups and destinations can be differentiated for the purpose 

of developing a set of metrics that together portray the diverse world of accessibility. Serving the 

same purpose, various modal options should be also considered. In households with no cars or 

too few cars, people rely on transit, where available, and other options.

Therefore, multimodal accessibility analysis is important for understanding the influence of car 

availability on levels of accessibility. Travel times as a measure of impedance may be 

determined for each passenger mode individually. With information available about the shares 

of carless and “car-poor” households, and about transit availability within Appalachia, a 

weighted average of travel times by availability of modal options can be formed and used as a 

multimodal accessibility metric (Figure 7). 

FIGURE 7 COMPOSITION OF A MULTIMODAL METRIC
Access in Appalachia: A Primer for Measurement and Decision-Making 19

Developing Accessibility Metrics

Developing Accessibility Metrics

How to Get Started

Identifying Methods, Data, and Resources

There is a variety of data for potential use to measure accessibility. The main purpose of this 

primer is to prompt engagement by transportation decision-makers with accessibility metrics. It 

is expected that approaches to accessibility measurement will vary across states, MPOs and 

agencies in the Appalachian Region. Each organization will have their own data, tools, and 

partners involved in accessibility measurement. This primer’s intention is to show how to 

measure accessibility, recognizing that any given approach may be right for some parts of the 

Region but not for others. 

However, identifying identical data and metrics for the entire Region would provide interesting 

opportunities to compare accessibility across Appalachia in a consistent manner. 

For User Groups

The user group is at the origin from which any accessibility measure is calculated. It includes 

both the specific constituency for which accessibility is measured and the geographic point that 

represents where the constituency is located. 

The geography can be captured in different ways. The first option is to use a pre-existing zonal 

system like traffic analysis which are used in travel demand models or census-defined statistical 

zones. Within each zone, a population-weighted, employment-weighted, or geographic centroid 

is chosen to represent the zone and to be the starting point of accessibility measurements. A 

second option is to use a standardized grid system, where accessibility is measured for each 

cell (e.g., 1 km x 1 km). Each option offers a different scale, leading to a more or less granular 

description of accessibility. 

A third option for geographic definition of origins may be to measure access for each location of 

interest, e.g., for each business of a certain size. A fourth option is to calculate a level of 

accessibility for each zone, weighted by measure of the number of affected users, e.g., a policytargeted measure such as number of people living below the poverty line.

For the Appalachian Region, given its scale and assuming a desire to conduct consistent 

comparative analysis, using a pre-defined standardized geography may be preferable. Because 

significant portions of Appalachia are sparsely populated, population or employment affected 

should be used as a weight. Insufficient access should not be deplored where areas are largely 

uninhabited. Weighting of user groups may additionally be extended to specific criteria that 

capture dimensions of economic disadvantage of people or businesses. 
Access in Appalachia: A Primer for Measurement and Decision-Making 20

Developing Accessibility Metrics

For Destinations

There are two fundamentally different approaches to defining destinations in an analysis. The 

first one is access to locations where activities happen, e.g., work (jobs), education, health care, 

or other services for people, or access to employees, markets, or customers for businesses. 

Some analyses simply count the number of establishments of a certain type (e.g., schools, 

restaurants), while others use indicators of magnitude, such as employment or population, to 

account for the scale of the destination’s attractiveness. The second understanding of 

destinations is access to important nodes on the transportation network such as highway 

interchanges, transit stations, or intermodal freight terminals. Such measures bring attention to 

the availability of modal options or proxy for the greater levels of access provided by these 

network “entry points.”

Source: ARC 

The Appalachian Region with its specific characteristics may call for a selection of destinations 

based on a hierarchy of need. However, given the sparseness of the transportation network in 

some parts of Appalachia, measures that focus on network access may also be appropriate. It 

should be considered that gains in access achieved by projects in the more sparsely populated 

rural areas can be smaller in magnitude but represent greater proportional gains relative to 

existing conditions when compared to similar changes in urban areas.
Access in Appalachia: A Primer for Measurement and Decision-Making 21

Developing Accessibility Metrics

Specific data for user groups and their specific geographic location (origins) as well as for destinations 

can be found in both the public and private realm. For 

population and employment, public census data is 

broadly available with a great level of detail. This 

gives a lot of flexibility when designing accessibility 

metrics, because they can be targeted to specific 

population groups or business industries. However, 

the use of both geographic and industry detail for 

employment may require the purchase of proprietary 

data, which is available from different vendors. 

Some data about destinations is collected by non-governmental organizations. This is for 

example the case for location data for health care providers. 

For Network Availability and Conditions

Network availability and performance determines (a) whether access is possible by a given 

mode, and (b) the “impedance” or effective resistance limiting access between the selected 

users and destinations of interest. Typical transportation performance variables like travel time, 

distance, and reliability, as well as direct costs like tolls/fares, determine the barriers to access 

perceived by travelers. A specific functional form dictates how impedance is quantified in the 

access measure. 

There exist several categories of network data:

• Network data may contain the network topology 

and characteristics like speed, from which travel 

times can be determined. Examples of this 

include OpenStreetMap, the Highway 

Performance Monitoring System (HPMS), and 

the Freight Analysis Framework (FAF). 

• Other sources contain pre-calculated travel 

time information, which may be estimated 

based on network characteristics or actually 

observed travel times. Examples for the latter 

include the National Performance Management 

Research Data Set (NPMRDS), HERE data, 

TomTom, and Esri StreetMap Premium.

• Routing systems provide a way to find the fastest routes between points and calculate 

associated travel times. They may be network data agnostic (e.g., Esri’s Network Analyst) or 

comprise integrated network data and routing systems. Examples for the latter include Esri 

ArcGIS Online (AGOL) and Google Maps.

• Tools for importing network data into routing systems provide interoperability between routing 

tools and data sets. For example, there are many ways to process and import OpenStreetMap 

data into routing systems.

Attributes of Origin 

/ Destination Data

▪ Geographic resolution of data

▪ Zonal or point data

▪ Availability of data

▪ Public or proprietary data

▪ Commercially offered or publicly 

available NGO data

Categories of Network Data and Tools

▪ Network data (topology and 

characteristics) 

▪ Pre-calculated travel times

▪ Routing systems

▪ Tools to import network data into 

routing systems

▪ Non-network transportation nodes 

and coverage data
Access in Appalachia: A Primer for Measurement and Decision-Making 22

Developing Accessibility Metrics

• Non-network transportation nodes and coverage data do not allow full network-based routing 

but contain data on the location of key multimodal transportation nodes or coverage of service. 

In this category, the National Transportation Atlas Database (NTAD) includes location data 

for intermodal freight facilities, ports, and airports. The Federal Communications Commission 

publishes data on fixed broadband and mobile wireless coverage.

Example Implementation

We calculate and map an access to trauma centers metric for four counties in West Virginia, 

according to the following methodology:

User Group: While for certain health care facilities it may seem reasonable to focus on specific 

age groups, for level 1 and 2 trauma centers all population is seen as the user group. We use 

census block groups as the geographic units for measurement at users’ origin. Access to 

trauma centers is a population-oriented measure. Therefore, the centroids from which travel 

times to trauma centers are measured are population-weighted block group centroids, with 

corrections to geometric centroids as necessary where the population-weighted centroid is 

located outside of the block group.

Destinations: Level 1 and 2 trauma 

centers located within the vicinity of our 

test area were identified by address, using 

the American Trauma Society’s “Find Your 

Local Trauma Center” tool.

32 These 

addresses were then geocoded using 

ArcGIS Online. Only four trauma centers 

were considered, all of which are situated 

outside of the study region. A full 

implementation of this measure would 

involve mapping other relevant trauma 

centers as well.

Network/Impedance: Travel times were 

calculated using the “Find Closest 

Facilities” tool of ArcGIS Online, 

calculating car drive times for this metric, 

without identifying a specific time of day for 

the calculations.

Results and Recommendations. Figure 8

maps accessibility to the closest trauma 

center within our test area. As accessibility 

in this case is not weighted by the 

importance of the destination or the 

number of trauma centers within a given 

area, accessibility is mapped directly as the travel time. The demonstration illustrates how a 

Source: ARC
Access in Appalachia: A Primer for Measurement and Decision-Making 23

Developing Accessibility Metrics

nearest destination metric can be developed and mapped to show where access is more or less 

constrained. 

FIGURE 8 TRAVEL TIME TO THE CLOSEST LEVEL 1 AND 2 TRAUMA CENTER (SAMPLE MAP)

Source: EBP analysis using data from the census, extracted using IPUMS NHGIS, the American Trauma 

Society, and ArcGIS Online.
Access in Appalachia: A Primer for Measurement and Decision-Making 24

Moving Forward

Moving Forward 

Opportunity

It is now becoming possible to build upon existing information sources and analysis tools to 

measure and portray levels of access among areas and constituencies. If desired, this can be 

done in terms of access to jobs, customers, health care, education, and other fields. The 

resulting insights can be critical in improving various transportation planning and decision 

processes:

• To improve areawide long-range transportation planning, by identifying areas of greatest 

accessibility deficiency and need for improvement;

• To improve transportation investment prioritization, by giving weight to projects that address 

the most critical accessibility improvement needs;

• To improve project planning, by identifying project alternatives that maximize improvement

in accessibility and economic opportunity.

There are many ways for regional and state agencies to work together to acquire and apply 

relevant datasets, develop mutual learning, and share knowledge to apply accessibility 

measurement methods. 

Outlook

ARC’s continued mission is to “innovate, partner, and invest to build community capacity and 

strengthen economic growth in Appalachia.33” It is in this spirit that ARC has been advocating for 

issues concerning rural Appalachia. Accessibility has been one of ARC’s major concerns when 

looking at obstacles to economic outcomes. 

Through this research and the resulting guidance document, ARC has developed an overview 

of specific Appalachian needs for access and ways to measure those types of access. In the 

future, ARC will continue to work collaboratively with and support state and regional partners in 

identifying access constraints and opportunities for improvements, including possible additional 

research and development of technical assistance tools.
Access in Appalachia: A Primer for Measurement and Decision-Making 25

Moving Forward

References

1 W. G. Hansen, “How Accessibility Shapes Land Use,” Journal of the American Institute of Planners 25, no. 2 (1952): 73-

76.

2 Susan Hanson, “Introducing Urban Transportation,” in The Geography of Urban Transportation, eds. G. Giuliano and S. 

Hanson, 4th ed. (New York, NY: Guilford).

3 Economic Development Research Group, Inc., and Investment Consulting Associates, The Role of Transportation in 

Private Firm Site Selection Decisions: A Primer for Transportation Planners and Decision-makers (Washington, D.C.: 

United States Department of Transportation, September 2018), Weblink. 

4 Glen Weisbrod et al., Assessing Productivity Impacts of Transportation Investments, NCHRP Report 786 (Washington, 

D.C.: Transportation Research Board, 2014), Weblink. 

5 World Bank, “Transport and Accessibility,” October 28, 2016, Weblink. 

6 Naomi Stein, “Accessibility,” in Encyclopedia of the UN Sustainable Development Goals, eds. W. L. Filho, U. Azeiteiro, A. 

M. Azul, L. Brandli, G. Özuyar, and T. Wall (New York, NY: Springer, 2009).

7 Derived in part from: Geurs and Wee. Accessibility measures: a literature review. Weblink. 

8 Glen Weisbrod et al., Assessing Productivity Impacts of Transportation Investments, NCHRP Report 786 (Washington, 

D.C.: Transportation Research Board, 2014), Weblink. 

9 Economic Development Research Group, Inc., and Investment Consulting Associates, The Role of Transportation in 

Private Firm Site Selection Decisions: A Primer for Transportation Planners and Decision-makers (Washington, D.C.: 

United States Department of Transportation, September 2018), Weblink. 

10 EDR Group and WSP/Parsons Brinkerhoff, 2017.

11 Brian Alstadt, Glen Weisbrod, and Derek Cutler, “The Relationship of Transportation Access and Connectivity to Local 

Economic Outcomes: A Statistical Analysis,” Transportation Research Record 2297, accessed December 11, 2018, 

Weblink. 

12 Amazon, “Amazon HQ2 RFP,” 2017, Weblink.

13 National Center for Education Statistics: Rural Education in America, Data for 2015, Weblink.

14 Molefe, A., Burke, M. R., Collins, N., Sparks, D., & Hoyer, K. (2017), “Postsecondary education expectations and 

attainment of rural and nonrural students” (REL 2017–257), Washington, DC: U.S. Department of Education, Institute 

of Education Sciences, National Center for Education Evaluation and Regional Assistance, Regional Educational 

Laboratory Midwest, Weblink. 

15 Science Foundation Arizona, “Making a Difference: Community Colleges Are Key Drivers of Rural Development,”

accessed December 11, 2018, Weblink. 

16 Andrew Crookston and Gregory Hooks, “Community Colleges, Budget Cuts, and Jobs: The Impact of Community Colleges 

on Employment Growth in Rural U.S. Counties, 1976-2004,” Sociology of Education 84, no. 4 (2012): 350-372.

17 Rural Health Information Hub, “Transportation to Support Rural Healthcare,” January 11, 2016, Weblink. 

18 Rural Health Information Hub, “Transportation to Support Rural Healthcare,” January 11, 2016, Weblink. 

19 National Academies of Sciences, Engineering, and Medicine, “Cost-Benefit Analysis of Providing Non-Emergency 

Medical Transportation,” Washington, D.C.: The National Academies Press, 2005, Weblink. 

20 Antonio Paez, et al., “Accessibility to health care facilities in Montreal Island: an application of relative accessibility 

indicators from the perspective of senior and non-senior residents,” International Journal of Health Geographies 9 

(2010), accessed December 11, 2018, Weblink. 

21 Samina T. Syed, Ben S. Gerber, and Lisa K. Sharp, “Traveling Towards Disease: Transportation Barriers to Health Care 

Access,” Journal of Community Health 38 (2013): 976-993.

22 Appalachian Regional Commission, “Health Disparities in Appalachia,” August 2017.

23 National Association of Community Health Centers: Removing Barriers to Care: Community Health Centers in Rural 

Areas, Weblink.

24 Christine Hancock, et. al, “Treating the Rural Opioid Epidemic,” National Rural Health Association, February 2017, 

Weblink.

25 Sara Lawrence, Zachary Oliver, Michael Hogan, and Sara VanLear, “Program Evaluation of the Appalachian Regional 

Commission’s Telecommunications and Technology Projects: FY 2004-FY 2010,” Washington, D.C.: Appalachian 

Regional Commission, November 2015, Weblink. 
Access in Appalachia: A Primer for Measurement and Decision-Making 26

Moving Forward

26 Federal Communications Commission, “Remarks of Commissioner Mignon L. Clyburn at the Launch of the Mapping 

Broadband Health in America Platform,” Microsoft Innovation and Policy Center, August 2, 2016.

27 Tomer, A., et al., “Signs of Digital Distress,” The Brookings Institute, Metropolitan Policy Program, September 2017.

28 Stein, 2009.

29 For example, Virginia DOT’s Local Assistance Access Programs: Weblink.

30 FHWA. Performance Based Planning and Programming. Weblink.

31 British Columbia Ministries of Health Services and Health Planning, “Standards of Accessibility and Guidelines for 

Provision of Sustainable Acute Care Services,” 2002. Weblink. 

32 American Trauma Society, “Find Your Local Trauma Center,” Weblink

33 Appalachian Regional Commission, “Investing in Appalachia’s Future, The Appalachian Regional Commission’s FiveYear Strategic Plan for Capitalizing on Appalachia’s Opportunities, 2016−2020,” Weblink