Criterion D: Results

Type I, Mathematical Investigation: Generalization

Achievement level

0    The student does not produce any general statement consistent with the patterns and/or structures generated.
1    The student attempts to produce a general statement that is consistent with the patterns and/or structures generated.
2    The student correctly produces a general statement that is consistent with the patterns and/or structures generated.
3    The student expresses the correct general statement in appropriate mathematical terminology.
4    The student correctly states the scope or limitations of the general statement.
5    The student gives a correct, informal justification of the general statement.

D0 Type I    The student does not produce any general statement consistent with the patterns and/or structures generated.

This could only happen with an assignment that was largely incomplete. Happily, I didn't have any examples to show.

D1 Type I    The student attempts to produce a general statement that is consistent with the patterns and/or structures generated.

Here the student has attempted a generalization, but it's not complete. His table indicates that he hasn't gotten enough of the pattern down -- he ignores the values from Pascal's triangle, and the probabilities on the side don't clearly represent anything in particular. You may also notice the messiness of the work. His handwriting is naturally atrocious, but on this page, he has actually made an effort to be legible. It doesn't remain this easy to read later in the response.
D1 I example 1
D1 I example 2

D2 Type I    The student correctly produces a general statement that is consistent with the patterns and/or structures generated.

Student 1

Earlier in the response, this student has gotten a correct general statement for the coin-tossing process. At this point, he tries to extend that to the general statement, but as you can see, he really hasn't done it. In fact, he succeeds mainly in being confusing.
D2 I example 1

Student 2

This example shows an incomplete general statement. He has sort of implied how a general statement would be constructed, but he never gets there. The exponents are missing from the description of how to do the computation (and a formula would be much easier to follow); he only really says how to get the coefficient from the calculator.
D2 I example 2

D3 Type I    The student expresses the correct general statement in appropriate mathematical terminology.

The conclusion here is incomplete. There has been a general statement in a previous part, but this conclusion does not have sufficient scope to constitute the general statement. It's an important distinction. Later in the student's work, he implies a fuller conclusion, but he never states it explicitly, which means that the "appropriate mathematical terminology" requirement is not met, either.
D3 I example 1

D4 Type I    The student correctly states the scope or limitations of the general statement.

This student did get level 4. He has stated what values of r and n make sense here, and in other places has addressed the numerical relationship of the probabilities of success and failure. What he does not do is explain why his process should produce the correct probabilities. This is why he doesn't earn level 5. You can see that in my last comment on the page I point out that he hasn't said why those powers produce the desired results.

D4 I example 1

D5 Type I    The student gives a correct, informal justification of the general statement.

These excerpts show how the student has explained why her processes work in two different parts of the assignment. Note that she's not just stating what she has done -- she's saying why it works mathematically. In the second example, she has a couple of notation problems, but she's done a good job of making clear why each of the computations is done. When she gives the general statement in generalized terms soon after, it is clear what she means, since she has worked through the reasoning here.
D5 I example 1

D5 I example 2


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