In message , at 15:16:32 on Mon, 11 Sep
2017, Someone Somewhere remarked:
On 11/09/2017 14:53, Roland Perry wrote:
In message , at 13:43:05 on Mon, 11 Sep
2017, d remarked:
It can be SMS,* it could even be electronic billboards or display
screens.* Imagine walking on to a tube platform, to be greeted by a
display with an advert from Boots - "Hey Someone Somewhere - you haven't
bought Preparation H recently.* If your arse grapes are still troubling
you, you'll be pleased to know that we currently have 50p off our jumbo
tube" or similar....
Of course there is always the option - possibly heresy for
Millenials - to
switch off wifi on your phone. I know, its radical, but it might
just work.
You've raised a *very* interesting point. This survey may be of only
that self-selecting subset of passengers who *do* keep their wifi on
[on the tube].
Does the associated article mention whether they attempted to
correct for this built-in bias?
Are you presuming that there is a correlation between whether people
keep wifi on and choose particular routes? If we assume they are
independent then TfLs analysis still stands.
Actuall, it's worse than that, because different types of traveller
might have smartphones or not, at all. Older passengers might have fewer
phones/device, and might make decisions based more on step-free or long
term habit, than short term optimisation. Conversely, younger people in
a hurry, with more devices, might bail out to alternative less obvious
routes more impatiently.
Presumably by analysing ticket data
You might be able to make a stab by comparing the number of ticket
barrier entries/exits at a non-interchange station or two, then the
number of unique phones you detect on the platforms.
we can see what percentage of passengers are carrying a device with
wi-fi enabled (although in my case that is often 3 or more - before you
ask, personal phone, work phone and kindle)
Well, that's going to bias the results too, because you'll perhaps show
up as three trips not one. And maybe people with lots of devices are
more prone to be fussy about choosing the quickest route.
--
Roland Perry