Feedback and testing of the dive statistics

[Dirk Hohndel]

> On Jan 10, 2021, at 1:55 PM, Peter Zaal <peter.zaal at gmail.com> wrote:
> 
> Just a couple of answers and additions to some of the comments to make myself more clear.
> 
>> - How many dives did I do in each country I dived?
>> Not possible, the Country is not available as a variable
> 
> Ugh. This is the whole dive site taxonomy thing all over again. I think this will require more thought. Because in the end what I think many will ask for is a full text search, but restricted to the location text plus taxonomy strings.
> Berthold, this sounds a lot more complex. Thoughts?
> 
> Ah, I thought Country was a separate field. In the Dive Sites tab it shows like that, but I guess it isn't.

I think it is a separate field, but ALSO a derived field in the taxonomy. So if we accept one, we'll have to accept the other or we'll confuse the heck out of our users, don't you think?

>> Then I looked at the data in the infobox, and it showed Min, Q1, Mean, Q3 and max. At first I thought this the Q1 and Q3 meant 1st quarter and 3rd quarter of the year, which made no sense to me at all. Where is Q2 and Q4. But it also didn’t change when selecting Quarterly or Monthly. Then I figured this is probably some statistics thing (I told you I am  a noob in statistics), and indeed it is. I do understand a little about the difference between mean and median, but is Q1 and Q3 something ‘normal’ people are interested in. Is this really something useful information, have not seen it anywhere else ever, and to me it just clutters the information.
>> What I did miss in the infobox is the number of dives it is about. If I select an operation like Mean, it does show an infobox with the Count. I would really like to see the Count also in the infobox on box-whiskers. And btw, vice-versa: when I select an operation I would like to see the Min and Max in the infobox on a bar
> 
> Yeah... when listening to some of the discussions during development, I appreciated how much more familiar Willem is with statistical terms. Mind you, I have a masters in math and understand how all this works, but the (English) terms and lingo threw me a few times. So Q1 and Q3 in this context are the boundaries of the first and third quartile and apparently these are indeed the standard terms that people use to refer to them. So I'm not sure how to communicate this better. Obviously the user manual will be able to help.
> As to whether this is useful information? This was certainly something that I wanted to have in the result because it tells me a lot more about how the data are distributed when I look at things. So yeah, I do believe this is useful.
> 
> 
> Yeah I understand that to statistics people this is very interesting information. On the other hand, I think most users of this statistics won't know about this (and not to be rude, but don't care). Even if it is explained in the manual (and I appreciate the work that goes into making a manual), this is always a last resort for people. Not a deal breaker for me, just my thoughts.

And as your thoughts this is valid and very much appreciated input. I'm not saying that we'll decide one way or another - I'm really curious to hear what others think

>> - The dive list on the lower left is disabled. The scrollbars are also disabled which is not very handy. Even better, if would be great if one could just double-click a dive to go to the edit-mode of that dive!
> 
> Ugh. I'm not sure I agree with that. It adds a ton of complexity. Unless you are ok with us leaving statistics mode for that...
> 
> Yes, I was not clear in that, but that is indeed what I meant. Just close statistics and have that dive selected.

That seems... doable. Something to add to the todo list, I guess.

>> - Binning for Water temperature: add 1 degree, remove 20 degrees
> 
> Disagree on both. 1ºC is realistically not consistently correctly measured by your DC - and worse, on basically every single dive that I have I always have multiple dive computers with me and they ALWAYS disagree by more than 1ºC. And in F it's of course even worse.
> And 20F is indeed a reasonable binning.
> 
> Ah. Yes agree about accuracy. On the other hand most people dive with just 1 computer ;-) And then it can be interesting to see a 1 degree Celsius difference, because it's relative to and valid for that computer.

I have also learned that even the delta between the different computers over a dozen dives is not constant. So I'll have dives where they are all within a couple of degrees, and two hours later they are 5 degrees apart (all in F, so adjust for C)
Still, I get your point.  Hmm. Not sure what to do here. Maybe we do need to offer different bins depending on F or C (see next point)

> Now I also understand the 20 value. For Celsius is not something you would often choose, but it is also not a problem to have it.
> Should we have different binning values for metric and imperial? Or does this make it too complex?

Berthold?

>> - The yellow warning icon on some charts is strange. I did read it means ‘it’s not the best chart’, but actually sometimes it provides useful information. I feel the warning icon should not be shown.
> 
> Willem should speak out on that as he has VERY strong feelings about this :-)
> Suffice to say that while these charts have useful information in them, they typically are marked as 'undesirable' because they can mislead in the way they represent the data. But Willem can do a much better job responding to that.
> 
> I think I read something about that before, but it was too complex for me.

In some cases it's fairly subtle, in some it isn't subtle at all. This is a crazy complex and diverse set of charts that we are offering :-)

>> - For the chart types there is a grouping of Histogram and Categorical. As said before, I don’t know much about statistics, and I am not really interested in this grouping, I just want to select a type.
> 
> But of course, the people who are most likely most interested in this feature are also the people to whom this likely makes a lot of sense. So we are trying to target the right audience here.
> One option would be to have a 'simple' UI mode... but that of course adds a ton of development work and testing overhead and... so I'm not sure if that's a good investment.
> 
> No I don't think so. I think the UI is quite simple enough and easy to use considering the many possibilities.
> This is just from my point of view as an ordinary user.
> 
> Already saw some PR's, so looking forward to an even better statistics module! :-)

New test binaries should be ready very soon. I noticed that something went weird when a faulty push to master confused my build servers and need to restart all of those builds for the latest master.

Give me about 15 minutes (of course it's midnight in Europe, so you may not be in a rush...) :-)

/D

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