Re: Some advice required [OT]

[Ben Bacarisse <ben.usenet@bsb.me.uk>]

Laurent <lutgenl@icloud.com> writes:

> On Monday, 27 December 2021 at 14:14:42 UTC+1, Ben Bacarisse wrote:
>> Laurent <lut...@icloud.com> writes: 
>> 
>> > On Monday, 27 December 2021 at 12:16:27 UTC+1, Niklas Holsti wrote: 
>> > 
>> >> Sorry, but I found your problem description impossible to understand. 
>> >> Try to describe more clearly the experiment that is done, the structure 
>> >> of the data the experiment provides (the meaning of the Excel rows and 
>> >> columns), and the statistic you want to compute. 
>> > 
>> > Sorry tried to keep it short, was too short. 
>> > 
>> > Columns are the antimicrobial drugs 
>> > Rows are the microorganism. 
>> > 
>> > So every cell contains a result of S, I, R or simply an empty cell 
>> > 
>> > S = Sensible 
>> > I = Intermediate 
>> > R = Resistant 
>> > 
>> > empty cell <S<I<R 
>> > 
>> > If a patient has 3 strains of the same microorganism but with 
>> > different resistance profiles I have to find the most resistant 
>> > one. Or if they are different I keep them all. 
>> > 
>> > I have no idea how to explain what I am doing to the compiler.
>> I think when you can explain it to people, you'll be able to code it. I 
>> am still struggling to understand what you need.
>> > Why I would choose result from strain B over the result from strain A. 
>> > 
>> > strain A: SSSRSS 
>> > strain B: SSRRRS
>> Let's space it out 
>> 
>> drug 1 drug 2 drug 3 drug 4 drug 5 drug 6 
>> strain A S S S R S S 
>> strain B S S R R R S 
>> 
>> You want to choose B because it has is resistant to more drugs, yes? 
>> 
>
> Yes indeed
>
>> I think, from the ordering you give, you need a measure that treats an R 
>> as "more important" that any "I" which is "more important" than an "S". 
>> (We will come to empty cells later.) 
>> 
>> I think you need to treat the number of Rs, Is and Ss like digits in a 
>> number. In base 10, the strains score 
>> 
>> R S I 
>> strain A 1 5 0 = 150 
>> strain B 3 3 0 = 330 
>> 
>> Now, in fact, you don't need to use base 10. The smallest base you can 
>> use is one more than the maximum number of test results. If there can 
>> be up to 16 tests (say) the score is 
>> 
>> n(R)*17*17 + n(S)*17 + n(I). 
>> 
>> If this suits your needs, we can consider empty cells later on. It's 
>> not at all clear to me how to compare 
>> 
>> strain C R____ 
>> strain D RRSSSS 
>> 
>> Strain C is "less resistant" but only because there is not enough 
>> information. In fact it seems more serious as it is resistant to all 
>> tested drugs. 
>> 
>
> Strain C is probably garbage and I would remove it. With a bit of luck I will have the result with the same sample Id which would be complete.
>
>> And then what about 
>> 
>> strain D SR 
>> strain E RS 
>> 
>
> Yes those are the cases which are annoying me.
>
> That's why I came up withe idea of multiplying the value of the result
> (S=1, I=2 and R=3) with the position of the value.  Tried it with
> triplets but there will still be cases where different results will
> give the same numeric value.  Ignoring empty cell able tps for the moment.
>
> Strain F: SSR (1*1+2*1+3*3) =12 and Strain G: RRS (1*3+ 2*3+3*1) = 12
> will be the same numerical value but they are different resistance
> profiles I would in this case keep both.
>
> How to prevent that from happening.

Can you first say why the suggestion I made is not helpful?

-- 
Ben.