crushthecurve

5 ms·

1.
by crushthecurve 6y ago
If there was a mobile contact tracing app that used AGPS with accuracy down to ~1m maybe it would be useful? Existing contact tracing apps use Bluetooth which can't be used to determine proximity with any reliability - solid objects
2.
by crushthecurve 6y ago
Contact tracing (of the human-powered kind) is obviously hugely important in reducing the scale of outbreaks in the early stages. However digital contact tracing has a fatal flaw: Bluetooth cannot be used to reliably estimate proximity in d
3.
by crushthecurve 6y ago
One of the numerous problems with the very concept of Bluetooth-based contact tracing is: it doesn't work. Due to all the hardware and environmental factors, it really works as a large spreadsheet of all devices in Bluetooth range over
4.
by crushthecurve 6y ago
It would be interesting to model two humans standing close to each other, and each phone on the closest side of the pairing, then on the opposite side, with the phones rotated at every angle. Having to traverse two human bodies will create
5.
by crushthecurve 6y ago
It's interesting to consider that Bluetooth cannot be used to estimate distance between two devices in any meaningful way in real-world environments. A recent article [1] confirmed this in interviewing the inventors of Bluetooth. The e
6.
by crushthecurve 6y ago
It's worth re-iterating how unreliable bluetooth signal strength is in estimating proximity. One recent data point using the CovidSafe app is here: https://twitter.com/jim_mussared/status/1256199078314078210
7.
by crushthecurve 6y ago
The assumptions of benefit appear to rely on a naive theory of instantaneous contact and isolation, when in practice the entire process is unavoidably manual, requiring human intelligence to ascertain environmental factors with which to mak
8.
by crushthecurve 6y ago
The project lead of Singapore's TraceTogether initiative goes into detail about the problems with an automated system, and why a human-in-the-loop is ideally required to evaluate the type of contact and make a determination. A determin
9.
by crushthecurve 6y ago
If someone is determined as a close contact they have to legally self-isolate for 14 days regardless of symptoms or test results. The policy there probably reflects the understanding that people in the early stages of infection won't t
10.
by crushthecurve 6y ago
Another consideration that seems to have been obscured by the debate on privacy and the narrow focus on the particular client implementation of the app is the significant problem of false positives and negatives. A lot of voices have spoken
11.
by crushthecurve 6y ago
In a regional context a bluetooth proximity app offers even less theoretical value. A contact is only registered after 15 minutes of time spent within an estimated proximity of 1.5 metres (itself a primitive model of infectious disease tran
12.
by crushthecurve 6y ago
A misunderstanding is that this system results in instantaneous contact notification and isolation (which is what one of the original papers on digital contact tracing efficacy assumes). The reality is the entire 'human in the loop&#x2
13.
by crushthecurve 6y ago
We took a deeper look in an article linked in another comment on this thread. One thing that's interesting to think about more deeply is how difficult it is to estimate proximity based on the combinatorial explosion of different hardwa
14.
by crushthecurve 6y ago
We've been looking at digital contact tracing from the perspective of Australia, as we see a huge push for the COVIDSafe app, based on Singapore's TraceTogether app. It seems the sensible order of questions is: 1) Do we have a con