Different information about count and last contact for high and low risk matches

[MasterEmit]

Feature description

It would be great to see a differentiation between low and high risk matches for count and last contact and not just everything as a summary.

Problem and motivation

For many days I just have had low risks with maximum 1 or 2 matches and often no risks at all. Suddenly some days ago I got 10 matches and red alert with the information that the last contact was 2 days ago. Now it's important to know that I almost do not leave the house except for running some days a week and thats early in the morning and without my smartphone. I do not meet people and live alone with my wife in my apartement.

So the big guess started why there are suddenly 10 matches with last contact 2 days ago. From day to day it seems that each day there is one match less displayed and the last contact days are increasing.
I used the Android App Beacon-Scope to check how many beacons I'm able to detect and with which kind of distance. In my flat I found quite many (changing of course) and in my sleeping room I was able to see 2 beacons which where under 10m distance. Holding my phone a bit higher to the ceiling the distance got lower. Now I guess that one of my neighbors above got positive tested.

The problem with 10 risk matches without any details is that you can't explain it. it could be 9 low risks and 1 high risk (where the contact may have been 11 days before) or you have 2 low risks and 8 high risks. With 8 high risks it would mean that I was in a somehow close contact with that person for some days.

Is this something you're interested in working on

Sadly no time :-(

[heinezen]

Hey @MasterEmit ,

Your request is similar to the features discussed in #100. The latest statement from the RKI can be found here: #100 (comment) .

Regards,
CH

---

Corona-Warn-App Open Source Team

[daimpi]

@MasterEmit This could nicely be integrated into #205

But as #205 it requires CWA to switch to ENF v.1.5+ and ExposureWindow mode.

[MasterEmit]

@heinezen I would not say that it is similar because I do not want a history. Of course this would be great but I would have some concerns related to privacy. For me it would be just fine to get a summary for each of both levels. But thanks for linking the other issue.

[daimpi]

@ndegendogo actually brings up a very good and subtle point here:

actually, I am not sure if the notion of "red" (high-risk) and "green" (low-risk) encounters is 100% correct, because they are not considered in isolation. Rather all these encounters are summed up, and contribute a large or a small amount to the overall risk

There are some green contacts which will contribute nothing because their "total risk" is smaller than 11 (i.e. smaller than the minimalRiskScore) but there will be others which combine together to trigger the "red" status even though each on their own would not suffice, exactly as in the example we recently discussed on the community Slack 🙂.
This would probably require some careful thinking how to label such cases, when it comes to the implementation of this issue here.

[ohobby]

From my own experience, I can report that reporting that you have had one or more low risk encounters, but you don't know when it happened, causes many people to panic and/or brood a lot about when and where it happened.
My partner and some friends are such candidates.
For this reason it would be very important that the date of the encounter is mentioned very quickly, even in the case of low risk encounters. This would help some users not to panic or brood. And prevent many requests to the health department and/or doctor.

[webermike]

Please show Date and Time of later on announced risk contacts, even if this leads to still having a green status.

As such contacts might occur only at shopping or eating in a restaurant, one can reconstruct with Date and Time where one habe been and if shopping or queuing anywhere is the risk reason.

This would enhance the analyse and discussion and avoiding of behavior in the future much, when it ia shown if the risk contact was at 8:00 in the bus ir at 12:00 in the McDonalds restaurant or at work at 10:00 o'clock at a certain date/day.

so it is not about "10 days ago" but about exact time and day.

Thanks for implementing that local showup fast.

[Blackjacx]

I got the idea too to show low/high risk encounters separately with date and time. I think this is a very good idea. Yesterday the app of a friend reported red and only showed 7 days ago for the risky encounter. Why do you make it that difficult? You can just show the exact date/time. This way reconstructing the behavior at that date would become much easier.

Also showing each separate encounter, is it low or high, with date and time would be beneficial to reconstruct what happened at that time. The summary as it is now could stay of course. I'm just an iOS developer but honestly I cannot understand how multiple separate encounters that happen in different locations could sum up to a total score. Why should the scores sum up when I have one encounter at e.g. work and another at the supermarket 2hrs later @daimpi. A quick explanation for interested people would be nice 👍

[daimpi]

@Blackjacx

You can just show the exact date/time.

This is currently not possible because the Google/Apple Exposure Notification Framework (ENF) doesn't expose exact timestamps to CWA: #206 (comment)

but honestly I cannot understand how multiple separate encounters that happen in different locations could sum up to a total score. Why should the scores sum up when I have one encounter at e.g. work and another at the supermarket 2hrs later @daimpi. A quick explanation for interested people would be nice 👍

This is a bit complicated, but the example we recently discussed on the community Slack (which you can join here) should help visualize how this can happen 🙂.

[ndegendogo]

multiple separate encounters that happen in different locations could sum up to a total score.

If you roll a dice very often, you will at some time get a six.
If you continue to expose yourself to the virus very often, you have a true risk to be infected.

[Blackjacx]

@ndegendogo thanks for the explanation tis simple dice example makes it clear already 👍

This is currently not possible because the Google/Apple Exposure Notification Framework (ENF) doesn't expose exact timestamps to CWA: #206 (comment)

@daimpi it could be done in a way I explained in corona-warn-app/cwa-documentation#433 (comment) which will already help a lot in avoiding irritation.

[daimpi]

@Blackjacx

it could be done in a way I explained in corona-warn-app/cwa-documentation#433 (comment) which will already help a lot in avoiding irritation.

Just to mirror your response from there:

But it would be possible to show the absoloute date for the reported day, without the time component for the reposrted day. This would already help a lot to not have to calculate in mind which day it exactly was. In a friends app there stand "risk encounter 6 days ago" and on the next day it was still 6 days ago, which can be very irritating! Writing the abs day solves this.

Yes I agree. The day of the most recent encounter (but not the exact timestamp) could indeed be shown and with ENF v1.5+ even differentiation between encounters on different days should become possible 🙂.

[dsarkar]

@MasterEmit FYI PR corona-warn-app/cwa-app-android#2397 will bring some more details