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Module 1: Pedestrian and Bicycle Level of Services

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Quantitative and Qualitative Pedestrian Levels of Services

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Let us introduce you to, uh, a new measure or a different other types of pedestrian level of services. As determined by the Indo at cm. This is especially looking at the quality of the service versus the quantitative level of service. So we'll give you an understanding of how these two levels of service have been developed, uh, in the Indo Axiom that has been, uh, uh, that has been published, uh, very recently in 2018. So there, uh, there have been, uh, various, uh, uh, uh, drawbacks or criticisms of purely quantitative, purely quantitative pedestrian levels of service, right. Uh, because the quantitative level of pedestrian levels of service are very similar or have been, uh, developed, uh, on the, uh, along the lines of vehicular level of service, um, researchers and experts. Uh, started to question them saying that, uh, uh, they may not be very applicable to a walking mode, which is very different from, uh, a regular form of transportation. So when two different modes, um, are so different from each other, uh, maybe there should be a different way of, uh, developing, uh, levels of service for pedestrians rather than, uh, developing it in her. Uh, similar fashion to that, of the regular level of service. So then, uh, what, uh, the first thing that came out of, uh, those kinds of Uh, brainstorming sessions was that, uh, perception of safety, comfort, et cetera, have to be taken into account because these, uh, it involves people who are walking on the streets. And as you walk, there is an always, uh, a degree of comfort. Uh, that, uh, allows you to, uh, gauge how well the physical systems are, uh, or the physical amenities are, or the physical environment is. So perception becomes a very, very important part. So perception of safety and comfort started, uh, becoming very important in the development of, uh, pedestrian level of service. Hence came. Uh, what is known as, hence the terminology was coined, which is known as quality of service, right? Rather than level of service, uh, or qualitative pedestrian level of service started to be called us quality of service. And the measure measure of effectiveness is user's perception. If people perceive that the facility is not good, that means they will not use it. Right. Even though it may be engineered. In a very, uh, good way, or even though the flow or the speed and the densities are all, uh, indicating that, uh, this is a good for pedestrians, but ultimately if the perceive that it is not a good facility perceive in terms of safety or comfort, then the usage of that facility will be very little. So we'll see how all this can be calculated. Exactly. Usually what happens, uh, how do we, uh, usually the way in which we capture, uh, the perception of people is honor Likert type scale. So it's called a Likert type scale where you ask people on such a scale. For example, a question may be asked that how, uh, much do you, like, how much do you like D. Four paths in your neighborhood. Right? If this may be a question, a hypothetical question that may be asked to you, uh, as a user, as a pedestrian, and you will be asked to give your rating or ranking of all these footpaths in your neighborhood. So you would say how much, uh, how much do you like, I strongly agree. You may say that I strongly agree. That all of the, um, uh, footpaths are good. Are the question should be, uh, how much do you, uh, to what extent do you agree that the foot parts in your neighborhood are serving the purpose, right. Are serving the purpose. So if that is the question, then you would say you strongly agree that they're serving the purpose. That means you perceive that it is very good. Or you say that I strongly disagree about anything in between. Right. So there can be variations in the scale. Uh, usually what people do is they fix, uh, the middle point and the end point, and then play around with the, uh, intermediary points. You can have a five point scale. Just like this one, two, three, four, five, or you can have a seven point scale. Sometimes people also have experimented with 10 point scale. So all of this have their own advantages. People are really started with a three point scale, but they have moved away from it, uh, to, uh, capture, um, users perception in a better manner. Right. Uh, a two point scale is usually yes or no. Uh, whereas a 10 point scale would be there a lot of intermediary points where people may strongly believe or not believe, uh, how well the, for example, the, uh, foot parts in your neighborhood are. So this is how usually, uh, data is captured about the quality or the perception of comfort or safety or any other parameters from the users of the pedestrian facilities. Uh, they are then, uh, they could be easily then converted into, uh, qualitative into quantitative, uh, figures and for the ease of, uh, calculations later on. However, one has to be very careful that, uh, since these are like a type data, uh, they are ordinal in nature. So it determines if one score is higher than the other, but. The distance between the points. So we, uh, is not known, right? So we don't know if this, and this is the same. We don't know if, uh, getting from your opinion, if your opinion has to be changed from four to five is the amount of work that needs to be done on the footpaths is the same, uh, versus, uh, if you, if your opinion had to be changed from three to four, Right. So in other words, when, uh, when an official or when a, uh, when a public, uh, public official receives such kind of, uh, ordinal data or receives this kind of perception data, Uh, he, the agency has to take a call, right? So nobody wants to build any facility and, uh, the user's not liking it. Right. So everybody wants that users to like the facility. Now, if everybody says, uh, the users say that, uh, they are only rating the facilities, uh, uh, sidewalk facilities as three on a scale of five. So, uh, the, uh, what the officials would want to do is. They want to calculate what they have to do in order to raise the, uh, um, perception of people from three to four. So there's some in order to do, do those activities, there are some money involved, right? There is some dollar figure involved, ROP figure in what? So when you're collecting this kind of data, it is not easy to say that the same amount of money would be needed to move from a three to four. Uh, which will be needed to move from a four to five. So we don't know the interval gap, but what all we know is four is better than three and five is better than four. That's all we know. So that's why a mean, an average is not usually a good measure of central tendency, uh, using mode. Just the count is always better. So in, uh, in the indoor it's, uh, 2010 method, W w what they have, uh, a measure that has been calculated is called the walkability index. What the walkability index does, is it determines, it asks such questions to every, uh, pedestrians and determines the importance of physical user characteristics. It determines the importance, and it also determines the satisfaction. There are two different questions that are asked. For example, uh, you may be asked how important are sidewalks, uh, for your, uh, for you to walk? Uh, meaning, uh, if you, uh, do you even care there are sidewalks, uh, for you to walk or you would just walk on the pavement. So you be asked to give an importance. On say a one to five scale. So you would say, uh, it is very important, meaning you will rate five. Uh, however, you'll also be asked, how satisfied are you with the current, um, uh, sidewalk network in your neighborhood then you would say, well, uh, it is very important, but I'm not at all satisfied. So I'm only giving her two. So on, on the importance you give a five. Out of five, whereas on a, uh, on a, uh, satisfaction, you only give it two out of five. So all you do is you do a weighted average of these two and you keep on asking this for, uh, all the users, uh, are a sample of the users in your neighborhood to get what you call a walkability index score. Now, this may be, I just give you an example of one question, but this could be done for different, different questions as well. Eventually after you calculate, after you get, uh, all of those, uh, uh, um, um, uh, weighted averages, you can then use this table, which was empirically developed and the, all the scales were in particular developed to determine what is the quality of service that you are pedestrian level of your pedestrian facilities are providing. So if your score is greater than one 24, You've added a very good, uh, quality of service. Whereas if it is less than 52, you are a poor quality of service. The next thing to remember is to give actually, or to define actually each of those physical land, user characteristics. So the physical characteristics have been defined using five different parameters. One is foot part surface on this foot part wit one is obstructions. Next is potential for vehicle conflict and the other is continued, right? So when, so if they are standardized and they're defined, then you can ask the same question to everybody without getting, I mean, without worrying about the fact that, uh, the question because of the variability in the way you are asking questions, people will answer it differently. So there is always a problem when you're collecting perception data. If you have not defined. The questionnaire properly, then people may give you different answers based on the way you ask the question. So, but to frame the questions or define the questions very, very properly. So when you say foot parts surface, you ought to say that a smooth surface without any cracks or bumps for comfortable walking is a very good surface, right? That is, uh, rated as the highest surface. And then you can have different layers up or different levels for. Footpath surface. Similarly, user characteristics are also defined using five different types of, uh, measures. One is encroachment. Yeah. There is availability of crossing facilities, security, comfort, the walk environment. So these are all user user centric or user characteristics, user behavior questions. So you CA you ask these 10 different questions. Five pertaining to the physical environment where people are walking five pertaining to what people feel about their trip, about their walking trip. You combine, uh, the findings of both of these questions and what it into a walkability index score, and then get that quality of service measure. Right. Um, again, uh, this is, uh, Um, these are importance score, five point scales and satisfaction score. Five point scales. Right. Remember we for each question, you will be asked two different subsets of questions. How important is it and how satisfied are you with the current situation based on this, you can then measure the quality of service. Like I just said, so for parts surface, once you defined, let's go back. So once you have defined foot surface as a smooth surface, without any crack for comfortable walking. So then that kind of, uh, qualitative, uh, um, uh, definition has to be broken down into five different levels, right? So the accent level will be even surface with no cracks or bumps. And uh, uh, flooring, right? Whereas very, whereas poor would be no raised foot path at all. Satisfactory would be bad condition, lots of bumps and cracks, whereas good would be moderate quality with few bumps in next. So these, again, remember these are qualitative aspects, right? We are looking at quality of service. So when you ask somebody about the perception, if you start asking numbers, Then they may not be able to give you good orders, right. Answered that will help you understand the perception of the viewer. So when you're asking to rate somebody how good the footpath surfaces you have to, yes, you have to divide them up into these five distinctly, but you also have to have a very reasonable or qualitative way of. Telling the, uh, asking the person what you want to know. If, if you ask, uh, for example, anyone asking a person, uh, how good a footpath surfaces and, uh, and say that, is it reasonable? Is it a reasonable quality? Walking is comfortable. They may be able to relate. Yes. Uh, I don't have any difficulty in walking, so maybe I will rate it very good. Or if you say that, well, uh, wasn't there any footpath at all? They said, no, there is no foot part at all. Then you would save. If there's no footpath at all, there is no question of a four part surface. So then you'd rate it, rate it as poor, right? So this is how you have to. Uh, you have to come up with scales for different parameters, uh, wit you can have a quantitative scale and you can actually measure it. You don't have to qualitatively ask anybody obstructions. Again has to be qualitative scale potential for vehicular conflict while they do continuity, some kind of qualitative and quantitative mixed. So once, you know, all of this, again, these are user characteristics, similarly defined, uh, for different scales. You can then go about and collect that data. So let us give you an example of, uh, how we have used it. Uh, in Indonesia, say a foot part of, with two meter in a residential area is to be redesigned and improved by giving importance and perception, importance to perception of pedestrians in terms of satisfaction. And the importance on various qualitative footpaths. Right? So a foot path was already laid, but when it was late, uh, user's perception was not taken into account. So now they want to redesign it, taking users perception into account. So, uh, the following of the mean importance and satisfaction ratings from 200 respondents accordingly. So what they found out was all these, uh, a one to eight, 10 are the questions that we have already looked at. We've already introduced you to under mean ratings have been found out to be these, uh, these are me. Uh, I, I believe these are important ratings and these are satisfaction ratings. Great. So once you know that if you are asked to ask the determine, if you are, if you're asked to calculate the walk-ability index and corresponding quality of service, all you do is right. You multiply each of them, each of the sets, each of the pairs, add them up and you come to a walkability index of 98.7, one or 99, 98% of 99. And you look up, look up the table. And you say that your quality of service that is being offered by the sidewalk, uh, currently is at . See quality of service, right? So then you can do always a post analysis. Now, if an improvement is done and you do another survey after an improvement has taken place, you would expect that, uh, if everything has been taken into account, if all the user's perception of taking into account, this C would at least improve to be if not to eight. So that is how you can then quantitatively. Uh, measure or qualitatively measure that users, uh, perspective has been taken into account while improving it facility? No, of course there are a lot of drawbacks on when you're looking at only qualitative stuff. Right. Based on user's perception, captures users, response comprehensively. Although people do agree that if you only look at quantitative aspects and don't take, uh, people's perspective, it will not comprehensively look at the scenario. However, the only source of analysis, if, if qualitative, uh, analysis is the only source, then they may be prone to inaccuracy reasons being. People are always not willing to, or, uh, not, uh, uncertain the questions in a very, uh, in a very proper manner. Maybe they are impatient. Uh, maybe they just want to get over with it. So they always, we have a tendency. If you are asked from great, anything from one to five, we always try to try to stick to the center. Right. We always try to pick. Uh, three, uh, one to five scale or result most of the times. So, uh, you are not able to get a proper or answer. Maybe the questions are confusing. Uh, if the questions are confusing, then you get different answers to different questions, uh, from different people. Uh, then again, relating this qualitative measurement with quantitative measurements is difficult. So if you don't quantify them properly into different levels, Then it becomes a problem. Hence it was, is suggested that both qualitative and quantitative, uh, yellow is, should be used for pedestrian facilities. So whenever you are actually judging the performance of a pedestrian facility, uh, you do have a quantitative measure. You then also have a qualitative measure, not just go with the qualitative measure or do not just go with the quantitative measure. Combine both of them and then take her call based on the existing conditions. Right? So again, if on a foot part, uh, it, we're looking at an, a next example on a foot part on an undivided bi-directional road with, with three meter around a terminal area, based on a field survey, the flow rate is found to be. A hundred and, uh, 1100 pedestrians, but 15 minutes, the football facility is bordered on the curb on boats, bordered by curb on both sides. And the important satisfaction is given based on a questionnaire survey that was done. So determine the BLOS and QoS of the existing footpath. Right? So would be the qualitative one, whereas Lois would be the quantitative one. And that would be based on. The flow parameters, which we have already explained in the previous, uh, uh, uh, in the previous set of slides in the previous lecture, how to determine the, uh, quantitative level of service or PLRs. And we now you've already looked at queuers. Let us see if you combine these two, uh, what do you get? Same answers, similar answers or not. All right. So let us start. Uh, so in, uh, identify in, in determining the quantitative PLR, you remember, uh, you had to follow six steps, which are already shown to you in the previous lecture. You identify, uh, the sidewalk based on land use. So here your land is terminal land use. Uh, you get a measurement of the sidewalk, width, you know, already sidewalk is three meter wide terminal land use. You estimate the effective with other facility. Do you remember how to determine the effect of it from the actual width you subtract the different types of obstacles that are there. And the, each of these obstacles have a certain shy distance associated with it. So here, since it says that it is bound by carbon both sides. So the PSI distance is anywhere between 0.2, 2.4. And if you just take an average of value, 0.3 on both sides and they subtracted from the total width. You say that the effective with this 2.4 meter, then, uh, you, uh, observed the pedestrian flow. You are already a given that the pedestrian flow is 1100 for 15 minutes. So permanent, your pedestrian flow is that you need to then estimate the peak flow rate. Uh, so a peak flooded is nothing, but, uh, you observed, uh, divided by 2.4 and you will get your peak flooded, right? Because 2.4 is the effective width. So if you divide it by a peak flow rate, remember is pedestrian per meter per minute. So there's four, 2.4 meters, if you want it per meter divided by that. So this is your floor. It now, you know, your floor it. And remember you remember this chart, uh, that gives you the quantitative BLOS. For each of the land uses now, you know that the land uses a terminal land use and your floor, it falls between this. So as per the, your level of services. See, so now you know that the quantity level of service based on the floor, it, and the effective it is servicing at the same time, you've already done a questionnaire survey and you've gotten that. Satisfaction and important score, importance and satisfaction score to determine that QoS quality of service. So you have all of these individual scores. Again, you develop a walkability index WWI and you get, it has, uh, 32.4, two or 33 based on 33. You will know the ER table and you see that it is less than 52. So now you see that the quality of service provided by the footpath that you have is. So here you have two conflicting answers, right? Comes to a quantitative pedestrian level of service. You're getting a C, whereas in you're getting a qualitative, uh, uh, quality of service. It is coming out to be E so what this does is if you had, if you had only, uh, developed this using engineering, uh, principles, then you would have thought that we'll see is the optimal level of service to have. So this is the footpath is perfect. However, if you, now, since you had already collected, uh, K2 survey and then a qualitative survey, you have said that you can. Now assess that this sot offer, uh, pedestrian, uh, footpath will be detested by users. Right? So now by doing that, you can understand that there's something has to be changed. Something has to be improved in order for it to be liked by all users, therefore, interventions that will help improve the quality of service has to be carried out. So that. You've get a balance between the quantitative level of service and the qualitative low service. So you see, through this example, I hope it is clear that if you only calculate the pedestrian level of service, uh, quantitatively, uh, you'll get, you may get a different picture, whereas you only calculate, uh, the quality of service QoS or the walkability through the walkability index. You may get different answers. So it's always good. Uh, to combine these two because, uh, um, uh, uh, pedestrians perceptions are very strong and have to be taken into account rather than only looking at it from the point of view of engineering design.