4.3. Activity Participation, Trip Behavior, and Travel Times

Another procedure used to determine the effect of non-sighted navigation on people’s lives is to examine the activities they participate in, how often they participate, and how long it takes to make the necessary trips.   Conventional accessibility measures have long used these types of data to help determine how much time or effort is required to access various locations.   These models have a utility function, which often assumes that people want to minimize time or distance in their daily trips.   In the travel environment faced by certain groups, especially those with limited vision, an examination is called for to determine whether time or distance expense is really the utility that they desire to minimize.

For instance, they might want to avoid busy or dangerous intersections, shop at stores with familiar layouts or personnel, or stay on a bus instead of making a transfer, even though these choices might increase travel time or distance.  Instead of searching for the most optimal spatial location, activities might be more focused on making sure the actual task or trip purpose can be performed easily and with less stress.

For a blind person, these are not “incorrect” decisions, as typical models would indicate.  There are other problems when using conventional accessibility methods to measure blind people’s accessibility, and, before discussing the data on time and trip behavior these other problems and difficulties are discussed, and an analysis is made of how conventional measures might not be suitable for the study of certain groups.
 

4.3.1. Accessibility and the Vision-Impaired

In Section 2.3 , Measuring Accessibility , accessibility measures and problems associated with accurate modeling were introduced.  In its most basic form, “accessibility” is a measure of an individual’s freedom to participate in activities in the environment (Weibull, 1980) .  Previously, a discussion of some of the restrictions on independent travel was made, such as time penalties, safety concerns, and the fear and stress that are faced by a traveler without vision.  These restrictions diminish the individual’s freedom to participate in accessing urban opportunities.  

4.3.1.1. Special Access Considerations for People with Vision Restrictions

Conventional accessibility measures assume “perfect knowledge” of the environment by users, meaning that they know of all choices for all activities.   Just like a visitor or new resident in a town who makes “incorrect” spatial decisions, many blind people can have trouble quickly assimilating enough spatial knowledge to afford them completely rational decision making.   The lack of access to printed signs, distal cues, and spatial and environmental information, as well as confinement to fixed transit and learned walking routes of travel, all restrict spatial knowledge acquisition.   Because of this, blind people might be unaware of changes and opportunities in the environment, even including what is available across a street or around the corner from their normal path.   Anecdotal evidence is replete with stories about blind people not being aware of changes in the urban landscape and of making “incorrect” spatial decisions because of the lack of spatial knowledge.   Work on feasible opportunity sets (Golledge et al., 1994) shows the effect of an individual’s spatial knowledge on the size and spatial configuration of the available choice set of locations when making spatial decisions.  Therefore, the blind person with restricted spatial awareness is an imperfectly informed decision-maker and might be faced with a limited opportunity or choice set when making spatial search decisions.    
 
When working with a subset of the general public, such as people with visual impairment, it is necessary to make sure not to confuse a measure of place or location accessibility with individual accessibility (how easily a person can actually reach activity locations).   Individual accessibility is determined not by the number of opportunities that are close by, but whether or not these opportunities are within reach, considering the person’s life situation and adaptive capacity (Dyck, 1989) .  Conventional accessibility models based on the proximity of locations of urban opportunities cannot account for the personal, highly diverse differences of human behavior and skills.   They often tend to actually reflect place accessibility, more than a measure of an individual’s accessibility.   Therefore, it is inappropriate to mistakenly attribute the locational or place accessibility, such as of a traffic zone or census tract, to a person in that area (Pirie, 1979) .  This conceptual framework is important in understanding the “true” accessibility experienced by blind people.
 
Because persons who are legally blind do not drive cars, they are often transit-dependent and, in addition, might need to make several transfers to reach a location.  These rides, and especially the transfers, can introduce much more travel time randomness into their trip.  In many cities, it is not easy to plan an arrival time when using transit and making transfers, and this certainly adds a great deal of variance to trip times.   In addition, people with vision restrictions might have to budget more time for unforeseen barriers, unfamiliar environments, or new obstacles in the environment.   Time constraints, spatial knowledge acquisition and processing, fear of new environments, safety concerns, and stress all figure in the spatial search equation for the blind.   For these reasons, traditional measures of access that rely on location-based properties do not capture the true accessibility of this group.  
 
For the general public in the built environment, all locations are accessible from all other locations.   There might be high levels of time, effort, or expense to overcome, but locations can be reached.  For people who use wheelchairs, areas and locations still exist that cannot be reached, no matter how much effort is expended.   The same appears to be true, in many situations and locations, for many visually impaired people when traveling independently.  
 
In previous sections, documentation was provided on the difficulty of tasks (see Section 3.2 User Rated Difficulty of Transit Tasks ) and the increased travel time required by navigation without sight (see Section 3.1 Caltrain Field Test ).  However, restrictions to access and travel go far beyond the increased effort and time.   There are locations that are so difficult to access that they form a barrier as formidable as a physical barrier is for users of wheelchairs.   If a street cannot be crossed, or a bus stop or entrance can’t be found, that one task can cause the whole trip to be abandoned.   Even one difficult street crossing can cause an entire area of the environment to become totally inaccessible.   In addition, a series of difficult tasks, especially in an unfamiliar area, can cause a trip to not be attempted at all because of daily time constraints and increased apprehension and fear.   Therefore, there are some trips that are not taken by this group even though there are no true physical barriers preventing them.   Access for the blind is restricted by more than time constraints, they also face barriers, such as the lack of spatial information, fear, confusion, safety concerns, and other perceived stressful situations.   Thus, independent travel for the blind can be blocked by the effect of the environment on the potential traveler.   These types of barriers to travel are not addressed in conventional measures that deal mostly with the physical relationship between locations.   
 
Gender bias and ethnic or minority bias can also occur in traditional accessibility measures.  Kwan (1998a, 1999) says that conventional spatial accessibility measures of access to jobs or shops are meaningless for women whose activity choices were continually complicated by additional time constraints due to their gender roles.   It is postulated here that people with vision restrictions also can face many constraints on their travel time and spatial knowledge, and that these can be quite different than those faced by the typical traveler.  
 
People with vision impairments might try to maximize a different utility than simple time or distance reduction, due to apprehension while in new environments and situations.   This, for example, leads to the belief that there also exists a “disabled bias” to conventional accessibility models.   In addition, different levels of an individual’s physical mobility (or mode of travel) can affect the distance or time effort of the shortest accessible path in small-scale areas, like buildings, such as the graphic display referred to by Okunuki, Church, & Marston (1999) or larger scale areas, such as a campus sidewalk network (Church & Marston, in press) .  Thus, there are often longer but still “correct” shortest paths that are used to overcome physical and other barriers in the environment.   

4.3.1.2. Spatial Mismatch and Interpreting Trip Time Data

Travel times have long been used as a measure of accessibility to various locations and functions.  There is little agreement, however, on how to interpret these data.   For example, a long work commute might represent a successful professional’s trip from a desired and isolated residential area to a prestigious job in the central city.  Conversely, a long work trip might be the result of a spatial mismatch between an employer-abandoned inner city and an employer-rich suburban area.   This situation often requires a long and arduous transit trip with many transfers in order to find employment.   A short work trip might be the result of child-care and other gender-role constraints on suburban women whose choices of jobs are from the many female-oriented jobs available in the suburban area.   In the past, short work trips were often associated with blue-collar workers who, for economic reasons, lived near the factory or warehouse.   However, a short trip can also result from a highly paid worker’s decisions to live in or near the central city.

The same inconsistencies are also found in other trip types, such as shopping, social, or recreational activities.   People with cars and economic resources might choose to live far from commercial locations and prefer to shop or recreate at various and prestigious places scattered around the urban area.   A short shopping trip could represent a person on a limited budget who is forced to walk and must perform these activities at a location close to home.  Conversely, an inner-city resident might be forced to take long trips by transit to find a full-service grocery store.  A short recreation-based trip might indicate that the only affordable spot is one they can walk to, while a long trip might be made by an economically successful person choosing to travel a long distance to play golf at different courses.   For these reasons, it is impossible to assess a “correct” interpretation of the true meaning of travel times and accessibility.   Examples of both long and short activity travel times are examined in the following data from the blind subjects in this experiment.

4.3.2. Activity Travel Times

In this section, the data collected about transit trip times, walking times, and the total roundtrip time taken to access various urban opportunities are reported.  Data were collected during the pre-test interview about subjects’ current weekly travel activities.   Subjects reported the number of trips they made for nine different activity purposes.   They also reported the roundtrip transit time and also their walk time.

4.3.2.1. Travel Time by Activity Type

Table 4.5 shows the mean roundtrip transit travel time, the walking time, and the total trip time in minutes.  Activities are shown sorted from the longest trip to the shortest trip.   Some subjects did not report walk time for their transit trip (cabs and other at-location pickups) and others walked the entire trip without using a vehicle.  For these reasons, the total trip times are not the simple sum of the total transit and walk times shown on the table.  

Table 4. 5  Transit Time, Walk Time, and Total Travel Time

Trip Activity

Transit Time

Walk Time

Total Trip Time

Round Trip Time In Minutes

Work

107

33

136

Education

63

33

84

Social

75

30

82

Entertainment

65

23

72

Religious

75

37

59

Recreation

44

33

54

Medical

38

16

38

Shop

25

27

35

Banking

18

23

26

Mean of those making trip

503

(8.4 Hours)

250

(4.2 Hours)

586

(9.8 Hours)

Mean for all 30 subjects

193

(3.2 Hours)

105

(1.8 Hours)

298

(5.0 Hours)

Many people did not make all types of trips.   The mean travel time for all the subjects was 3.2 hours in-vehicle and 1.8 hours walking, for a total of 5.0 hours of travel per week.   The data in the table and that discussed below are only for those who reported making a trip for that activity.   The mean weekly travel time for those who made trips was 9.8 hours, with 8.4 hours riding a vehicle and 4.2 hours walking.   The use of private car rides was very low, as reported in another part of the interview.  Almost all trips were made independently using public transportation, and the term transit is used here to include any vehicle ride.    
4.3.2.1.1. Work Trips
The mean transit time for those who made work trips was 107 minutes; they walked 33 minutes, and the total roundtrip time was 136 minutes.   There were 17 trips reported, and 17 people reported transit use and two people did not report any walk time.   The longest work trip was 390 minutes and the shortest was 30 minutes.   
4.3.2.1.2. Education
The mean transit time for those who made trips to participate in educational activities was 63 minutes; they walked 33 minutes, and the total roundtrip time was 84 minutes.  There were eight trips reported, six people reported transit use and walking, one reported transit only, and one reported walking only.   The longest education trip was 165 minutes and the shortest was 30 minutes.   
4.3.2.1.3. Social
The mean transit time for those who made trips for social activities was 75 minutes; they walked 30 minutes, and the total roundtrip time was 82 minutes.  There were 25 trips reported, 12 people reported transit use and walking, nine reported transit only, and four reported walking only.   The longest social trip was 270 minutes and the shortest was 10 minutes.
4.3.2.1.4. Entertainment
The mean transit time for those who made entertainment trips was 65 minutes; they walked 23 minutes, and the total roundtrip time was 72 minutes.   There were 16 trips reported, 10 people reported transit use and walking, three reported transit only, and three reported walking only.  The longest entertainment trip was 150 minutes and the shortest was 20 minutes.
4.3.2.1.5. Religious
The mean transit time for those who made religious trips was 75 minutes; they walked 37 minutes, and the total roundtrip time was 59 minutes.   There were 12 trips reported, three people reported transit use and walking, one reported transit only, and eight reported walking only.   The longest trip was 200 minutes and the shortest was 10 minutes.
4.3.2.1.6. Recreation
The mean transit time for those who made trips to recreational locations was 44 minutes; they walked 33 minutes, and the total roundtrip time was 54 minutes.  There were nine trips reported, four people reported transit use and walking, one reported transit only, and four reported walking only.   The longest trip was 105 minutes and the shortest was two minutes.
4.3.2.1.7. Medical
The mean transit time for those who made medical trips was 38 minutes; they walked 16 minutes, and the total roundtrip time was 38 minutes.   There were six trips reported, three people reported transit use and walking, one reported transit only, and two reported walking only.   The longest trip was 60 minutes and the shortest was 20 minutes.
4.3.2.1.8. Shopping
The mean transit time for those who made shopping trips was 25 minutes; they walked 27 minutes, and the total roundtrip time was 35 minutes.   All 30 subjects reported making shopping trips, 10 people reported transit use and walking, eight reported transit only, and 12 reported walking only.   The longest trip was 130 minutes and the shortest was two minutes.
4.3.2.1.9. Banking / Financial
The mean transit time for those who made banking trips was 18 minutes; they walked 23 minutes, and the total roundtrip time was 26 minutes.   There were 15 trips reported, three people reported transit use and walking, no one reported transit only, 11 reported walking only, and one person reported no extra time (ATM at the store).   The longest trip was 65 minutes and the shortest was 10 minutes.

4.3.2.2. Travel Times per Person

There is a large variation in reported total trip times and trip frequency.  The mean weekly travel time was 5.0 hours.  Figure 4.1 shows the data for each subject sorted from lowest to highest weekly trip times. 

Figure 4. 1  Travel Times per Person

 

One subject reported travel of only 20 minutes per week, while another traveled 40 minutes per week.   Three more traveled between 1.2 and 1.7 hours per week for a total of five who traveled two or fewer hours during the entire week.   Ten subjects reported total travel time between 2.5 and 3.8 hours per week.  Five traveled between 5.1 and 5.9 hours, while another six reported times between 6.3 and 8.0 hours.   Three reported times of 8.8 to 9.4 hours, and one person (a salesman) reported 15.5 hours of weekly travel.  To better understand these data, it must be kept in mind that these subjects were not among the estimated 30% of blind people that Clark-Carter, et al.  (1986) say never leave the home for independent travel.   These subjects had the training, skills, and motivation, to travel to the test site in downtown San Francisco.   Most subjects did not live in the City and so many traveled quite a few miles from across the Bay or from South Bay areas.   It must, therefore, be expected that mean travel times and the number of trips reported would be even lower when considering the entire population of people with vision restrictions.

4.3.3. Activity Participation and Trip Frequencies

A compelling reason to live in a large urban area, especially for those who do not drive a car, is the large range of activities and urban opportunities that are available and easily accessible through mass transit.  When considering all the daily activities a person has to choose from, the following data provide blunt evidence that people with vision restrictions face limitations in their activities and travel, and that there are major restrictions and barriers that affect everyday life activities for this group.

Figure 4.2 displays the number of trips reported by the subjects, sorted from lowest to highest frequency.  The mean number of trips reported was 12.1 per week.  

Figure 4. 2   Total Trips per Person

The activities and trips that subjects reported included any function that took place outside the home.   The data on individual activity participation show a wide range, and the variation warrants a closer look at individual behavior.   Nine subjects (30%) participated in only seven or less activities in an entire week (one per day.)   Three subjects left their home for two activities during a week, one apiece reported 2.5, 3.5, and 4.0 trips, two took five trips and one took seven.   Another 13 subjects (43%) reported 14 or fewer activities per week.   From the sample of 30 blind subjects who were active and skilled enough to navigate to the test site, fully 73% participated in two or less activities outside their home per day.   Another five   subjects reported between 15 and 21 trips per week, and one made 23 trips.   Two subjects reported high trip and activity participation of 32 and 35 trips per week.   These two young adults were part of a residential program, had useful vision, and were very social.  They reported many trips to visit friends in adjacent apartments and regarded their many trips to the local “hangout” corner store as either social or shopping.    

4.3.3.1. Trip Frequency by Activity

The previous section reported on the number of trips actually made by the test subjects.  There is more to understand about trip and activity behavior of the blind than just explanatory statistics and descriptions of actual trip frequency patterns and distribution.  Trip frequencies and activity participation data are widely used by marketing professionals, and urban and transportation planners.   A major principle in transportation planning is that, by removing barriers to access and increasing throughput, accessibility in the system can be increased, and no one seems to deny that curbs and stairs are major barriers to activities for those using a wheelchair.    
Transportation planners can easily compute the effect on accessibility of improvements such as wheelchair accessible buses, a new limited-access highway, a new transit line, an express mode, or the elimination of airport service by comparing trip behavior before and after the change.   Urban planners can judge the effects on accessibility in the environment caused by the installation of curb-cuts and ramps, a new pedestrian mall, or a parking structure.   They can determine the effect of a big-box mall at the edge of town on downtown business by comparing previous and current trip behavior after the change.   Although accessibility models can help estimate these changes, these types of comparisons of trip data can only be made after the change has been implemented.  
 
The ability to make such comparisons in order to understand accessibility for the blind has been limited, if not impossible.   If people’s sight could be restored, it might be possible to make such comparisons.  If RIAS was already fully installed in an urban area, comparisons of the data before and after the installation could easily be made.   Some kind of comparison of the blind subjects’ data to other data is called for, but a simple comparison to data from the sighted would not uncover much of importance.  Since there is no full urban installation of RIAS, hypothetical travel behavior information was collected from the subjects.   In order to research the accessibility of this group, some questions were asked that have not been researched before.   Prior to subjects’ exposure to RIAS but after the actual weekly trip data were collected, it was asked if there were trips that subjects did not make because of problems with their visual impairments’ effect on their independent travel and the efficient use of transit.   The actual questions asked were:

  • “Do you sometimes avoid trips or activities because of your visual impairment and the difficulties of independent travel?”
     
  • “If YES, how often during a week do you avoid these types of trips or activities because of your visual impairment and difficulties of independent travel?”
     
    The questions were worded this way to try and avoid any frivolous or fantasy desires or activities.   Of the 30 subjects, 20 (67%) said that they avoid some trips because of travel problems caused by their vision loss.   Those who said they avoided some trips reported how many and what types of trips were not taken. 
     
    During the field experiment, subjects experienced transfers to different transit modes, including a large terminal and street environments that were rich in RIAS installations.  After the experiment, subjects reported how many more trips they would make if RIAS was as richly installed in their environment as they were at the test site.  All but one subject (97%) reported they would make additional trips with the addition of RIAS in their daily activity space. 
     
    Collecting data on currently desired, but not taken, extra trips and trips they perceived they would make with RIAS installed produced three data sets to examine.
     
  • The actual trip data
     
  • The actual trip data plus the desired but not taken trips (total trips currently desired)
     
  • The actual trips plus those trips they would make if RIAS was installed (total trips they would make with RIAS)
     
    In the discussion, the terms “actual,” “desired,” and “would make with RIAS” are used to identify these three data sets.
     
    The desired trip data when added to the actual trip data gives a type of control group for comparison.   These data represent the “best-case” scenario as reported by the subjects if they did not have travel problems relating to their blindness.   Comparison of these three data sets reveal which and how many trips vision impairment and transit access currently limit and if the addition of directional and identity cues through a navigation system is estimated to reduce or cancel these limitations.   If “would make with RIAS” trips are less than the (control group) desired trips that would show that there were other problems associated with the limitations of navigation without sight.   If the “would make with RIAS” trips were higher than the desired trips, it would show that the system was perceived to open up more participation in activities and urban opportunities than the subjects had previously considered possible.   If that is the case, it suggests that the lack of spatial cues in the environment is a limiting factor in blind travel.   Just like the elimination of physical barriers for those using wheelchairs, this would show that it is the environment and its barriers that limit movement and travel, and not the people and their visual condition.   The “desired but denied” data reveals “pent-up” demand that is not currently being met.  The “would make with RIAS” data reveals what transportation planners call hidden demand .  Highway engineers know that after carefully planning the future capacity of a new highway, based on existing travel data, the road is soon at full capacity not long after completion.   Thus, there was a hidden demand that was not revealed until the new link was available.   The demand is hidden because people change and increase their use based on the new accessibility offered.     
     
    Table 4.6 shows the three data sets.   Since all 30 of the subjects did not make all types of trips, the number who reported them is shown as (N=).   The different trip types are sorted with the most frequent currently conducted activities first.  The average number of actual trips reported was 12.1 trips per week.    

    Table 4. 6   Actual and Desired Trip Making Behavior

    N =

    The # of

    subjects who reported making this type of trip

    Actual Trips

    Made

    Actual +

    Desired Trips

    Not Made

    Actual +

    Extra Trips

    With RIAS

    N =

    Mean

    Trips

    N =

    Mean

    Trips

    N =

    Mean

    Trips

    Shopping

    30

    2.6

    30

    3.3

    30

    4.9

    Social

    25

    3.1

    28

    3.6

    27

    5.0

    Work

    17

    4.7

    17

    5.0

    24

    6.7

    Entertainment

    16

    1.4

    20

    2.0

    25

    2.7

    Banking

    15

    1.3

    19

    1.5

    25

    1.7

    Religious

    12

    2.2

    14

    2.6

    15

    2.6

    Recreation

    9

    2.3

    19

    2.2

    25

    3.1

    Education

    8

    3.5

    13

    2.6

    23

    3.2

    Medical

    6

    1.3

    6

    1.3

    8

    1.2

    Other

    0

    0

    1

    1

    0

    0

    Total Trips

    30

    12.1

    30

    15.8

    30

    25.0

      
    When the trips that they did not make because of travel limitations were added, the average number of trips they desired rose to 15.8, a 31% increase. This is a realization that the number of trips they do make now is 23% less than what they desire.   The subjects’ data inform that there are strong limitations on daily activities that are associated with loss of vision, independent travel, and transit use.  After using RIAS, subjects perceived that they would make 25.0 trips per week, a 107% increase, or, they estimated they are only making 52% of the trips they would make with RIAS. 
     
    All subjects already made shopping trips, and no subjects thought they were missing any work or medical trips.   For all other activities, an increased number of people thought they would participate if it weren’t for the problems of independent travel and transit use related to their vision loss.   If they could use RIAS, still more people expressed an interest in participating in all activities.
     
    For the currently desired trips, the mean frequency increased for all activities except recreation and education.   Both of these activities had high increases in the number of participants, and the total number of trips was higher, but the mean was lower.   For the “would make with RIAS” trips, more people desired to participate in activities than they currently did for every activity type, and except for social (with one less person), more people said they would participate than they had expressed in the “desired but denied” question.  The total number of trips per activity was higher than the actual and the perceived data in all cases.  The frequency mean was slightly lower for medical trips, and it was equal for religious trips.  A comparison of the three data sets shows that many activities are denied to these blind subjects in both number and frequency.   Even more important, it shows that travelers perceive the lack of simple environmental cues as a major cause of this limitation and that, with the addition of these cues, blind people could make more trips and more could participate in these activities.   This is an example of what has been earlier described as functional barriers to travel and transit, and the elimination of these barriers should substantially increase accessibility and activity participation.   To see how these barriers limit travel for different activities, the percentage change both in the number of people who said they would participate and in the number of trips they said they would make is discussed.  
     
    Figure 4.3 shows theincrease by percent of the ‘desired” and “would make with RIAS” trips over the actual trips reported.   The data are ordered from high to low, based on the desired but denied trip data.  
     
    About 2/3 of the subjects were congenitally blind and had never experienced vision.  The rest also had no current chance of regaining sight.   Their acceptance of the restrictions of vision loss on their everyday travel was quite evident from their rather conservative estimates of the number of trips they thought they were denied because of their vision loss.   They expressed a desire to take an additional 99% more trips to recreational events and 79% more trips for entertainment purposes.   It could be argued that these two activities are the most discretionary of the group, and, therefore, the ones that are first eliminated because of any problems.  Banking, religious, shopping, and education trips were desired from 40% to 21% more than their actual frequency.  They only desired to make 6% more work trips, and none desired to make more medical trips
     

    Figure 4. 3  Additional Trips Desired and Estimated

    After experiencing RIAS at the experiment site, subjects appear to have learned much about what could be accomplished easily and safely using the additional cues.  Before trying the system, only 20 subjects (67%) thought they were missing any trips, but after usage 29 (97%) thought they would make more trips.   The number of trips they said they would make with RIAS was much higher than they had originally thought they were missing.   Discretionary trips, such as recreation and entertainment, were still the two highest in terms of the increase, but at a much higher rate, 269% and 198% respectively.  Estimated education trips increased by 165%, banking trips by 110%, and work trips were perceived as increasing by 100%.   Next in decreasing order were shopping (87%), social (73%), religious (45%), and medical trips up 27%.  
     

    4.3.3.2. Increased Number of Activities and Trips per Person

    This section examines how perceived trip behavior changed for individual subjects.  Of the 30 subjects, only one person, who already took 13.5 trips per week, reported she would not make any more trips with RIAS.   Five subjects said they would make between 12% and 49% more weekly trips, and another five said they would make between 50% and 99% more trips.   Ten subjects said they would make between 100% and 199% more trips, four more between 200% and 299%, two between 300% and 399%, and two reported extra trips between 400% and 499%.   One person, who currently made only two trips a week, reported 12 extra trips if using RIAS, for a 600% increase.   Clearly there is a hidden demand for more activities if travel and transit was made more accessible, a demand for inclusion and participation that has not been previously understood.
     
    Activity participation can also reveal the degree of access.   Figure 4.4 shows the increased number of people who said they would attend to new activities   The data are again sorted from highest increase to lowest for those that reported activities that they were denied because of transit and travel limitations relating to their blindness.  
     

    Figure 4. 4  Additional Desired and Estimated Subject Participation

    For the desired trips not taken, recreation and education trips had the highest demand by additional participants; a 111% and 63% increase, respectively, over the actual number of current participants.   Banking, entertainment, religious, and social trips were estimated to increase, by 27% to 12%, for the number who would participate.   No one reported that they did not participate in work strictly because of independent travel limitations.   They also felt they were able to meet their medical trip needs, and, since all subjects made current shopping trips, there was no increased desire in that category.  These numbers seem to be in line with what one would expect.   Except for the first two discretionary activities, the estimate of foregone participation was quite low or non-existent for critical functions like work and medical. 
     
    If all 30 subjects participated in each of the nine activities, the total number of person-activities would be 270.   The actual trip data showed 138 person-activities. Subjects indicated that they currently wanted access to an additional 28 person-activities for a total desired participation of 166 person-activities, an increase of current unmet demand or desire of 20%.
     
    The possibility of making new activities part of their everyday lives with RIAS was quite evident in the number of people who said they would participate in more and new activities.   The total number of person-activities perceived if using RIAS was 202, an increase of 64 from their current level of participation.   This is a hiddendemand or desire for 46% more subject- participation in totally new activity types, after exposure to the experimental test site with its auditory cues.  
     
    The “desired” data showed that recreation and education activities had the highest percentage of increase of subjects wanting to participate.   The same pattern held true for the number of additional people who said they would make those kinds of trips if RIAS was installed.   Education was said to attract 188% more people if they could use RIAS.   The number of people currently making education trips was eight, and five more thought they were being denied those kinds of trips.   But, after using RIAS, 15 additional people stated a desire to attend educational activities.   Clearly, this group valued education, but problems of access kept the number of current participants quite small.   With RIAS, 178% more subjects desired participation in recreation activities then their current level while 67% and 56% more people reported banking and entertainment activities, respectively.   The next two activities that subjects said they would make were not even chosen in the “desired, but denied” question.   Originally, there were 17 people who made work trips, and no additional people desired to make them.   However, after experiencing RIAS, an additional seven, or a 41% increase, said they would participate in work activities and make those types of trips.   In addition, six people reported making current medical trips, and no one expressed that they postponed these kinds of trips because of their inability to travel independently.   However, an additional two, or 33%, said they would make that kind of trip if RIAS was installed.  An additional 25% said they would attend religious activities, and 8% more said they would make social trips.  As everyone already made shopping trips, there were no additional participants noted.

    4.3.4. Summary of Current Activity Participation, Unmet and Hidden Demand

    This section has presented data showing travel times, trip frequency, and activity participation.   A summary of the basic findings for these blind subjects shows:

  • Many subjects do not travel very much, and their trips can be quite short.   These people do not often leave home to participate in activities, and their trips appear to be quite close to their home, restricting their activities to familiar areas.  They are denied access to opportunities that are available to others in the same area.
     
  • For those who do venture out into the wider environment, their trips are often quite long.
     
  • Activity participation was quite low for many subjects.   Three people left home only 2 times during a week, 30% of subjects participated in one or less daily activity outside the home, and 73% of all subjects made 2 or less activity trips per day.  
     
  • 67% of subjects reported that they were denied some activities because of visual problems affecting independent travel.  
     
  • They reported they would make 31% more trips if they could travel independently.  
     
  • After experiencing the additional environmental cues of direction and identity that could be delivered through the use of RIAS, subjects were able to more fully understand that they could gain more access to urban opportunities.
     
  • They reported they would make 107% more trips if RIAS was installed in their environment.
     
  • There was a reported 46% increase in the number of new types of activities that subjects would participate in if RIAS was installed.
     
  • None of the subjects originally thought they did not have access to work because of their lack of independent travel.   However, after using RIAS, an additional 41% said they would make work trips.
     
  • Subjects reported trip frequencies for work trips would increase 100% if they could use RIAS.
     
  • Participation in educational activities was desired, after using RIAS, by an additional 15 people over the current level of 8, a 188% increase in the demand for education.  
     
  • Estimated trip frequencies increased 165% for education activities if RIAS was available.
     
    Marston & Golledge (1998b) and Marston, et al. (1997) have suggested that one cause of the dismal unemployment level for the severely vision-impaired, 70%, (Kirchner et al., 1999) is the difficulties of independent travel.   That includes not just the daily job commute, but, perhaps more importantly, the ability to execute a successful job search strategy when jobs are located in various and scattered urban locations.   As non-drivers, the available jobs or educational opportunities for people who are blind that are located in familiar areas must be much less than the aggregate available to the sighted public.   That 41% more people thought they would participate in work and 188% more thought they would attend education facilities adds empirical evidence to their argument.  
     
    The data in this section about trip behavior indicate that blind people feel they face barriers that limit activities and opportunities because of the lack of environmental cues that restrict independent travel.   They often are restricted to local and familiar areas, and many appear to limit their trips and activities to needed functions with a smaller participation in more discretionary activities.   Both the number of trips and the types of activities are restricted.
     
    When the environment is made more accessible though the use of additional cues, blind subjects perceived their lives as having many more types of activities and a much higher participation rate in those activities.   RIAS appears to reduce the perceived limitation of independent travel by providing a much higher level of accessibility to blind users.

    BACK TO OVERVIEW
    BACK TO TABLE OF CONTENTS
    NEXT SECTION