[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [school-discuss] Collecting Assessments at District Level



hello,

On Scaling : --> fitting data topology to need and demand.

two seperate factors must be scaled :

(1) Quantity

If I must keep 10,000 100 byte records (A) per 9 week term,
with four measured terms per year
then the volume of the data will grow by 
4A per annum.

this is a number all your vendors need.

(2) Accessability

if one hundred users access together the average wait is ~
% fails rises on slope @ with volume to M

you respond to these motivations by publishing  agreed to service levels.
this ties service to a transactional cost.
"Within 30 days, late orders 72 hour delivery on notification of tardiness 
and so on ..



benefit --> you can observe tradeoffs between cost, effectiveness and public 
image. (Response time and failure rate are the major impacts of record keeping
operations on public image of the institution.  ( Purely based on 
observation, not statistics. )

let's take :

50 folders of 100 bytes each : 
5000 bytes - 50 folders by one backup : 10000 bytes - 100 folders
by 40000-400  (four measured terms) annual 

for 10 users with 8 record accesses over the total population of folders : 
10x8x400 = 32,000 accesses

if all accesses occur exactly on the four term boundaries
on a single 6 hour day in each of these four instances 
and an average fetch is one minute user time (at the client / terminal )
each day you can do 360 transactions
but you need to do 8000 in this period
so you can either :

a : drop the transaction time.  at one second,  it's at 21,600 - overshoot !

b: lengthen the publishing period.  at 6 days of 7 hours each 2520 (not good 
enough to meet anticipated demand).

these worst case rough cuts establish scalibility goals - the end points.
this approach lets you size the ruler you're going to use.

vendor relationships could start with this number ?

my "hunch" is that growth in accesses for a given folder show high demand for 
at most 5 measured terms to span years, then they decline on an exponentially 
increasing ( if negativce ? ) slope i.e. people look at newer records more 
than older records and that as the distance along that line increases so does 
disinterest.

you can design a solution with these numbers.

i would use two brand new wal-mart 1gig athalons
with 2 40 gig drives
and 256 meg memory 
and standard redhat 7.2
maybe swapping out some parts
more than enough to do the job, but,
price and value count too :-)

there are better math guys than me on every street corner,
so the idea is a little rough cut, but
... well - you tell me.


mike eschman, etc ...
not just an afterthought
http://www.engima.com





On Wednesday 13 March 2002 09:48 am, Stephen Braunius wrote:
> Thanks for the response!  I'll try to clarify my situation by responding
> to your questions:
>
> Les Richardson wrote:
> >1) What format are the assessment items in now? Are they in just raw text
> >or are they marked up in some fashion...Tex, HTML, etc. or are they just
> >collections of files in proprietary formats like Word, Wordperfect, etc?
>
> Currently we are collecting or converting all assessment data into CSV
> files using either FMPro or Excel.  These assessments are typically
> either percents or scales from 1-4.  Everything is currently tagged to
> our district assigned student id's.  These assessments are created as a
> part of our curriculum rewrite/revisit process.
>
> >2) How do you want these items to be assembled into tests?
>
> The assessments are actually cumulative scores (kind of like final
> grades).
>
> >3) How are you going to classify these items so that they can be usefully
> >retrieved?
>
> This is what I am struggling with.  I don't know how best to store the
> data to be meaningful over a long period of time.  Is it best to have a
> table with characteristics of each assessment (year given, score type,
> scale, quantatative/qualitative, curricular area, etc) and a table with
> just data and the associated test?
>
> >4) What kind of output formats do you want to generate?
>
> I would like an individual teacher to be able to pull up information
> about each student, the average for their class, and the average for the
> building in each area.
>
> >5) Who has access both for retrieval and for entry/editing of existing
> >items?
>
> Currently all entry is coordinated by me using CSV files imported into
> MySQL with with fields like this: student id, score1, score2, etc.  They
> are then associated with a table that has some very general test
> information.
>
> >So, I'm willing to help out with some opinions or code if you wish. I use
> >a MySQL database and Perl/DBI for my testbank. Markup is either raw text
> >or TeX for the items.
>
> Thanks for the offer.  I enjoyed looking at the testbank stuff you have
> created.  It looks like you have already worked through a lot of the
> items for how to collect assessment data.  I wish there were some site
> out there that has a diagram for how best to create the database tables
> for creating an academic assessment warehouse.
>
> Wow, if anyone made it to the end of this email and actually understood
> what I was saying I would be amazed. ;^)
>
> I'll see how many people have ideas on this topic and will then probably
> contact you outside of this list since the topic probably isn't of
> interest to everyone.  Thanks again for sharing your work.