On categories and dimensions and zooks

Jason,

Abyot…

Can you explain me this further? Because if I got you correct - you are

saying you couldn’t do aggregation by dimesnsions which are not included in

the category combos.

I think it is clear that I can create data elements for the data entry

sheet I sent the exisitng cateogry combo functionality. This seems

straight forward, except we are using 1.4 here as the data collection

tool, and 2 analysis and presentation purposes. That is another

complication, but anyway, lets assume it is possible, and it certainly

seems to be the case.

Then for me… you are trying to do something else

which is not envisioned during data collection. If a dimesion can not be

constructed from the category combos (and corresponding options) then this

dimesion shouldn’t be asked during analysis.

I must completely disagree with you. As I stated previously, a DHIO

asked me two weeks ago, "How do I calculate the total incidence of

vector borne diseases?" Well, I said, You can create an indicator for

this, and add every vector borne disease to it and divide it my the

population. Seems reasonable. A bit of work, but it seems possible.

However, it gets stickier when you think about beginning to slice and

dice the data. Would an indicator need to be created for every

possible combination of diseases, age groups that we could possibly

dream up? If so, then we can completely do away with the PivotTables,

as we can just define an indicator for every possible combination that

we can dream up! This does not seem practical.

Another solution, as Johan just points out, is that we can use

different data element groups for this purpose. This seems possible as

well I guess. DHIS 1.4 and 2 will allow you to do this, but it does

result in a data integrity violation as entries in the resulting

PivotTables will be duplicated. Sure we can lump them together, but

which table tells me that two data element groups should be lumped

together? The problem is the lack of data element group sets (like

organizational unit group sets). If there was, then I think everything

would be fine (at least I think).

I am only convinced of one thing from this whole discussion - that we need

to extend the API so that we can do aggregation of different combinations

for the available (collected) atomic dimesion elements. As far as the MD

model … I can take your comments for renaming some of the objects - but

I don’t see a limitation in the model. But again everything is open here -

and anyone can take it further. I am just sharing my views as I was the

central person in the MD issue.

Well, my problem is that in my case, the data elements have not been

created as multidimensional from the beginning, thus the need to group

them into dimensions afterwards. I agree, as the categories have been

implemented now, it seems totally possible to create a data entry form

for the Excel sheet I have sent you. No problems there, it is just in

the analaysis that we are missing something.

In reply to Johan,

Vector-borne diseases can be a DE group.

But why can’t it be a category as well? This is a matter that is still

not clear. Where should the categories start and data element group

sets take over? Anyway, this is more of an academic question, and not

entirely relevant. it would seem that creating categories-category

combos should be used for data entry, and that data element group sets

should be used for anaysis.

If data elements have a category

inpatient/outpatient, you can easily get only outpatient data from the

pivot table (or, as many other countries: have two headcount elements for

each form: Total inpatients, Total outpatients). Communicable and

non-communicable diseases can also be an DE group, and if you don’t want

DEs to belong to two groups, you can lump them together with a query or in

he pivot table.

How can I lump them together in a PivotTable if I cannot determine

that they are in a group set together? I can hardwire it in the query

with regular expressions to pull out all instances of OPD, IP and

Deaths in data elements. I can create a supporting table and populate

them with data elements, but how will it be maintained and accessible

through the UI? I have done both of these things, but I do not think

it is part of the current functionality.

Anyway, to summarize this, as it seems we may be nearing some consensus.

  1. Current functionality for category-category combos is sufficient

for the purposes of multidimensional data entry, and provides enough

functionality for analysis of data based on the dimensions defined

during the data element creation.

What it seems is missing is the ability to isolate a category in, for example, a report table. So if there is an Age-Sex categorycombo on Malaria, you cannot isolate Malaria by Sex without also bringing Age. This may not be a problem. If it is we can probably solve it through API

  1. Current functionality for grouping of data elements by dimensions

for analysis is insufficient and needs to be extended to include the

concept of data element group sets.

Funny. We seem to have the opposite problem here with the above. If I understand you right you are saying effectively we cannot create multiple dimensions by composition because data elements can only be members of one group.

And presumably this also applies to indicators.

Yes. That is why I so eagerly pushed data element/indicator group sets yesterday. We need it for exactly this purpose.

···

2009/10/1 Bob Jolliffe bobjolliffe@gmail.com

2009/10/1 Jason Pickering jason.p.pickering@gmail.com

Regards
Bob

Capiche?

Regards,

Jason

Best regards,

Jason


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