Saturday, June 4, 2011

Sample Testing

People who need something quantifiably simple and repeatable to judge how well schools are doing find test scores to be remarkably convenient. Test scores can then be used to fill colour coded spreadsheets that act as a carrot for the successful schools and a stick for the under-performing.

The problem is that even the most test-loving psychometricians know the limits of testing. They understand that even the best tests are merely samples of a larger domain and making inferences based on these tests must be tempered with the understanding that all tests have an element of error that must be compiled with multiple measures.

The problem with census testing is that we get cocky and reckless with the results. Just because everyone writes the test that doesn't change the fact that the test is still nothing more than a sample. Those who are not familiar with testing seem to think otherwise.

While it is true that I am not a proponent of testing, even I can see how moving from census to sample testing could be a step in the right direction. Here's what I mean:

When we hear the results of political polling, we would never say "well, if we have polling, why do we even need to bother with the election?" When it comes to polling, I think even the most uninformed understand that polls are merely samples of the entire population - polls may be informative but they are not a substitute for the actual election.

If testing was done only by a sample of the population, I think it would be much harder for anyone to sell testing as a substitute for other more authentic and direct measures of learning. Sample testing would help us all to understand that the tool chosen to tell us about our schools cannot do what we ask of it.

2 comments:

  1. I like this concept. We participate in SfL, acronym that I no longer know what it stands for but know it is somehow related to learning. With SfL we are supposed to focus on a sample, or slice as they call it. Whereas your idea is supposed to test just a portion of the population, SfL still tests the whole population. The difference being that you are supposed to look at justnthe sample's results to determine what you are doing as a teacher is working. Either way there is faculty logic in the practice because of the innumerable factors that play into using humans as test subjects. So then, would your sample become completely random, and the tet subjects chosen by lottery much like drug testing that occurs in baseball or jury duty in the Uniited States? Or would the sample chosen be determined by the state, district, etc. who would require that you have representation of all your subgroups to prove that you are closing the academic achievement gap? I'm with you, eliminate standardized testing all together.

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  2. Great analogy, Joe! We've tried to use the same argument here in Ontario. Our students do very well on random-sample national and international tests, yet our government believes that every child needs to be tested. Can you say 'public accountability'??

    I mentioned to you that we submitted our position paper on EQAO (recommending a move to sample-based testing) to the Drummond Commission as a potential cost-saving. It is here: http://www.otffeo.on.ca/english/media_room/briefs/new_vision.pdf In February, the EQAO published a paper that appears to be a 'response' (defense??) to our paper. It is here: http://www.eqao.com/pdf_e/12/PowerOntProv_TestingProg_en.PDF

    We believe that they really didn't like our paper. At least, if that is true, we have their attention!

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