northbank

it's so good we have so many experts in traffic management on this forum. just a shame none of them take the step to work somewhere they could make use of this expertise

https://www.surveygizmo.com/resources/blog/representative-sample/ This explains sampling frames and representative samples

The London travel demand survey is done every year with 8000 households, not people. It is sampled to be representative of all Londoners in terms of demographics and geography. You don't need 5% of the population for it to be representative https://tfl.gov.uk/corporate/about-tfl/how-we-work/planning-for-the-future/consultations-and-surveys#on-this-page-1 spartacus Wrote: ------------------------------------------------------- > Hi ExDulwicher > > Can you publish the modelling work you did or > share it on here ? if you are going to talk about > it let others see it. > > The TfL London Travel Demand Survey you shared was > for 2011 /12 and is made up of 8,000 responders > therefore it is 8 years out of date and only > represents 8,000 ( > https://tfl.gov.uk/corporate/about-tfl/how-we-work > /planning-for-the-future/consultations-and-surveys > #on-this-page-1 ) out of 9,304 million Londoners > (2020 figures) which means the survey represents > approximately 0.086% of the total London > population ? that?s worse than a Loreal advert > that tells you 85% of 120 women prefer it? > > If the survey was done with a realistic sample > then it would represent the views of Londoners, > however with such a small survey there is a chance > that (for example) 1,000 parents questioned on > their way to take little Johnny to football could > easily bias the results. > > The data is a) out of date and b) not a large > enough sample to produce the full conclusion of > 35% of all car journeys are less than a mile (2km) > > > To use this survey in a meaningful way in this > debate you would need to ensure it covers at least > (modelling finger in the air) 5% of all Londoners > (465,200 Londoners or half a million for ease of > counting) which would provide better objectivity > and a more reliable outcome. > > I agree, for some people the creature comfort of > driving rather than waiting in the cold and wet is > better than using busses / trains but a lot of the > journeys undertaken would involve multiple changes > or long awkward journeys (when I was younger I > used to commute, not by choice, to Kent on a daily > basis which was only practical by driving as an > example.) > > Remember this area is a through route to other > places (Kings College Hospital, the South Circular > and so on) so a lot of drivers in this area (not > SE22 resident's) are possibly doing more than > local short journeys. > > God I would love to own an Aston Martin as I > suspect 99.99% of all drivers would, but two > points to mention here, there are not that many > Aston Martins in Dulwich and as much as I would > love to say ?Bond, James Bond? sadly motability > cars don?t offer an Aston Martin as an option > 😆 > > To follow up on your comment, you need to think > that a lot of cars in the area are owned by > families with kids who need to carry them and > other things in the safest and quickest way from A > to B (cycling, walking and Public transport often > doesn?t offer an option.) > > The concept that people still drive company cars > is also a bit out of date, over the past 20 years > tax advantages of doing so have been eroded so now > the number of company car drivers is very low > compared to 2000 or 2011.) > > The issues with the scheme needing to bed in over > months (as you point out) would be true if there > was a limited number of LTNs but that?s not the > case as they are virtually everywhere in London > now so traffic can?t evaporate to other roads as > they are also blocked hence demand is forced into > ever decreasing bottlenecks pushing pollution in > certain areas even higher. > > I will accept that some journeys are unnecessary > but until you provide the following I can?t put > any faith in your stock answers as a lot of people > actually do need to drive but the pro-active > travel lobby are making life hard for them and > increasing (not reducing) pollution as a result.. > > 1. A copy of the modelling work / or link to > it with the base date behind it. > > 2. A current 2019/20 London Travel Survey > (preferably with a good respondent group to ensure > that small deviations can?t skew the data.) > > 3. Local data on drivers in and around East > Dulwich including those who pass through. > > 4. A pre implementation traffic and > pollution survey for all roads in the area to show > either the overall improvement or the displacement > to non LTN roads.

Metallic Wrote: ------------------------------------------------------- > Maybe they are short because the driver can't walk > that far, or has too many kids to handle plus > shopping, but most of them aren't http://content.tfl.gov.uk/analysis-of-cycling-potential-2016.pdf

Rockets Wrote: ------------------------------------------------------- > rahrahrah Wrote: > -------------------------------------------------- > ----- > > A significant number of car journeys in london > are > > only a couple of miles btw. > > > Let's dive a little deeper into that because I > know Cllr McAsh said in his blog that the majority > of journeys in London can be walked or cycled. > > Here's TFLs data > > 35% of all car trips are shorter than 2km. > 32% are between 2km and 5km. > 30+% are over 5km. > > What I can't find from TFL is whether taxis and > private hire vehicles are included in these stats > - which would of course skew them massively in > central London. > > People can make their own minds up now based on > the actual data. They are private car trips. Taxi and PHV trips are recorded as that and are a tiny percentage compared with private car. The Travel in London report combines them both into 'Taxi' at 1% of all trips with car at 35% http://content.tfl.gov.uk/travel-in-london-report-12.pdf

Penguin68 Wrote: ------------------------------------------------------- > 35% of all car trips are shorter than 2km.... > > You have to be a bit careful about these figures. > If you set off on a long trip, stop at a garage > locally for petrol, and then continue, that's 2 > trips - once under 2km, and one longer. That's one trip with two stages. " A trip is defined as a one-way movement from an origin to a destination to achieve a specific purpose, for example, to go from home to work. Each trip may involve travel by one or more individual modes of transport. These component parts of trips are referred to as journey stages. Key concepts relating to trips, journey stages and main mode of travel were explained in detail in Travel in London report 5, including the assignment of a main mode to each trip based on the journey stage by which the longest distance is travelled (as part of a whole individual trip)." http://content.tfl.gov.uk/travel-in-london-report-12.pdf >It depends > very much on how they are being both recorded and > reported. Broadly (and it makes sense) the figures > give a reasonable view - mostly (60% of the time) > you travel within around 5kms of your starting > place before returning - though who you're with, > what you are carrying and the purpose of your > journey are ignored. As is the state of the > weather and the time (you're more likely to take a > car if you plan some part of your journey out or > return when public transport you could use isn't > running). Other criteria for switching from car in here http://content.tfl.gov.uk/analysis-of-walking-potential-2016.pdf Criteria - Filter Encumbrance - The person making the trip is carrying tools or heavy work equipment. Age - Trips of more than 1.5km made by those aged under 12 or over 69; trips of more than 2km made by those aged 12-69. Current mode - Trip made by van, dial-a-ride, plane or boat. Trip chaining - The trip is part of a wider chain of trips that cannot be walked in its entirety and here http://content.tfl.gov.uk/analysis-of-cycling-potential-2016.pdf Criteria - Filter Encumbrance - Person carrying a heavy or bulky load Trip length - Trip is longer than 8km Journey time - Trip would take more than 20% extra time to cycle Age - Traveller is over five and under 64 Time of travel - Trip is made between 8pm and 6am Disability - Traveller has a disability affecting their travel Current mode - Trip made by van, dial-a-ride, plane or boat > > And if you're running a relatively (or completely) > 'clean' vehicle - electric or hydrogen > (eventually) the number and length of your trips > will be completely irrelevant when it comes to > issues of pollution. Which is the future that many > people are looking to - but if the cycling brigade > get their way, and we are forced out of having > cars, the necessary economies of scale for an > electric or hydrogen future will be lost. If > people don't or can't, buy sufficient numbers of > the cars, they will be generally unaffordable - so > the only motorists left will be the wealthy. > Considering the socialist (indeed Marxist) > background of so many of the campaigners surely an > unintended consequence? "A literature review carried out for the European Commission concluded that about half of all particulate matter results from brake dust, road dust and tyre erosion" https://www.imeche.org/news/news-article/this-is-why-electric-cars-won%27t-stop-air-pollution

dougiefreeman Wrote: ------------------------------------------------------- > Nigello Wrote: > -------------------------------------------------- > ----- > > Dougie ? of course it?s a fact. It?s self > evident > > they?ve chosen to drive. Nobody forced them. > They > > chose. The alternatives may be less convenient > but > > they still chose to do it. > > > > It?s really simple ? if we want less traffic > then > > everyone must reduce their use of motor > vehicles. > > People don?t like this fact so they invent > > distractions and whatabouts. > > > > Drive less and use fewer services that use > motor > > vehicles and traffic will reduce... Give it a > go! > > Ahh I think I get it now, you think it?s a fact > because you say so? > > Just in case there was any misunderstanding > before, I was asking you to provide your evidence > / source for your claim that the bad traffic was > made up of people who?d made a ?short journey?. I > was wondering how on earth you could possibly know > that. We?re you knocking on windows asking them > how far they?d come? Or do you have access to some > data that the rest of us don?t? "A little over a third (35 per cent) of all car trips are shorter than 2 km, just under a third (32 per Cent) are between 2 and 5km and the remaining third are longer than 5km"

 Londoners make 3.6 million daily journeys by motorised modes (car, motorcycle, taxi or public transport) that could be walked, at least in part  1.6m are made by car  Shopping and personal business account for the highest share ? 37 per cent ? of all potentially walkable trips. This is largely equal to the profile of existing walk trips, where nearly four in 10 trips are made for shopping or personal business purposes http://content.tfl.gov.uk/analysis-of-walking-potential-2016.pdf  Londoners make 8.17 million daily trips by motorised modes (car, motorcycle,taxi or public transport) that could be cycled,  4.7m are made by car  Almost half of all potentially cyclable trips are made for shopping and leisure purposes, with one in six made for commuting reasons http://content.tfl.gov.uk/analysis-of-cycling-potential-2016.pdf Spartacus Wrote: ------------------------------------------------------- > march46 Wrote: > -------------------------------------------------- > ----- > > thebestnameshavegone Wrote: > > > -------------------------------------------------- > > > ----- > > > We need to have fewer car trips in London. > It?s > > > really simple. You?re either pro low traffic > > > stuff. Or you?re pro more car congestion. > > > > > > Well said. I heard a stat the other day that 1 > in > > 7 car journeys in London is under 1km - this > isn't > > sustainable. Making the car the least > convenient > > option and at the same time creating safer > spaces > > for people to walk and cycle is essential. > > Have the 1 in 7 stats identified what these under > 1km journeys are for ? > > If they are, for example, family shopping runs to > the supermarket then they are possibly justified. > > > The information behind the stats is just as > important as the stats themselves.

http://content.tfl.gov.uk/technical-note-14-who-travels-by-car-in-london.pdf slarti b Wrote: ------------------------------------------------------- > mr.chicken Wrote: > Drivers skew rich, white, male and middle aged > > You may well be right but can you point me to your > evidence for this statement for London drivers so > we can compare withe the profile for commuter > cyclists? > > btw are you a support of Margy Plaza ?

Slarti_B's (and TfL's ) interpretation is correct, and you've misread the table on p111 of the TfL report, Mr Chicken. The final column where it says '50:50 Male:female' is of the 'LTDS whole sample'. This demonstrates that the sample is not biased as it matches the distribution of the London population and can be used to see if the demographics of the cycling population is skewed in any way compared with the general London population The column you should be looking at for cycling demographics is that sub-headed '2018/2019' which shows that those who have cycled in the last year are 62% male, 78% white and 64% employed; all proportions that are higher in the cycling population than the London population. In terms of age, those 45 and older are under-represented in cycling and those under 24 are over-represented. and for income, those with a household income less than ?20K are under-represented while those higher than ?75K over-represented hence the correct interpretation "Most people who cycle in London.. tend to be mostly male, white, in employment, and with relatively higher household income" mr.chicken Wrote: ------------------------------------------------------- > slarti b Wrote: > -------------------------------------------------- > ----- > > mr.chicken Wrote: > > > -------------------------------------------------- > > > ----- > > > > > Says "actually" and makes a claim with zero > > evidence. Are you a One Dulwich supporter by > any > > > change? > > > > I was quoting the TFL "Travel in London" report > 12 > > from 2019. The precise quote is "Most people > who > > cycle in London.. tend to be mostly male, > white, > > in employment, and with relatively higher > > household income". Happy with that? > > Glad you provided a source for your evidence, yes. > It allows me to verify your claims. Somehow that > quote doesn't appear to match the data. On P111, > it gives a 50/50 split male/female. It does skew > white (slightly less then car ownership), and as > for higher household income, the large 20k-70k > band is the highest, with the 0-20 and 70+ bands > showing equal representation. There's a slight > skew towards the employed, at 55/45. > > Basically you've overinterpreted the data in your > favour. > > > > I would much > > prefer to see a holistic solution that does not > > split East and West Dulwich and that achieves > the > > objectives of the OHS scheme. What does that > have > > to do with your comment? > > Ah yes a "holistic solution", one that doesn't > involve you actually specifying what this magical > solution is, just that it's out there somewhere. > This is the thing, none of the people objecting > actually have a solution which is better or even > as good. And no, doing nothing is not as good. > > > > Metallic Wrote: > -------------------------------------------------- > ----- > > > > Oh. Ever actually thought that if there was > > better public transport in certain areas, that > > people wouldn't NEED a car? The reason many > > people don't need a car is because they live > near > > multiple bus routes, can walk or cycle, or have > a > > tube line. > > I bet if we block off a load of roads we'll fine > that fewer people NEED a car than claim and on > closer examination merely WANT a car. And what > better way to improve public transport than to get > lots of cars off the road?