Thursday, June 19, 2014

Correlation coefficient of linear fit?

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The Common Core State Standards Initiative has, in its High School Statistics and Probability section, the statement 
Compute (using technology) and interpret the correlation coefficient of a linear fit.
You can find it here.

I suppose I can accept the utilitarian notion of being able to computer something on a calculator while having no idea where it comes from, as long as the result can be interpreted correctly.

I do have a problem with question 11 from the New York State Algebra I (Common Core) exam. 

I see nothing in here involving interpretation or understanding. All I see is a question asking whether or not the student could remember a cook-book recipe from their calculator's user manual. Pity the poor teacher whose students have the gamut of calculators. (After all, school cannot be a mandate for using a certain company's products.)  I must assume that this question is not testing the students ability to state the coordinate names for the points, as the question requires a number of steps beyond that.

What I do see here is a lousy test question. 

As for the relevance of the topic itself, well, that is debatable. If Algebra I is considered as an introductory high school course, I say absolutely not. Comprehension of correlation coefficient requires a skills base and a time commitment better suited to a later course. If Algebra I is considered an exit exam, perhaps the situation changes. Since New York now considers Algebra I regents exam as both an introductory course (anything below it is considered remedial) and an exit course, in a one-size-fits-all scenario, things are very confusing.

By the way, I looked at NYSED's page regarding this test. It is here, and as of today, all its links are password-protected. 

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