Normalization: Comparing the Chapter and the AI Guide¶
This page compares two pages on normalization:
Putting Each Fact in One Place (Normalization), the student chapter (
normalization.md)Normalization — A Guide for the Teacher, the AI-written guide (
normalization-ai.md)
It covers the core teaching content only and leaves out the exercises. It sets out where the two agree, where they put the emphasis differently, and where the guide claims something the chapter does not support. It ends with the one difference that matters most.
Where They Agree¶
The core question is “What is this fact about?” Step 3 of the chapter becomes step 2 of the guide’s session. Both say it has to be written down in pencil, with the computer off.
The structure is the same. Both have three passes (one value per box, the key, the fact hiding behind another fact) and two tests: cross out a row, and change a fact and count how many boxes you fix, which should be one.
The three failures are the same: a change that has to be made in several places, a fact that cannot be recorded, and a fact that disappears with a deleted row.
The names come last. The chapter puts “Now the words” after the work, and the guide says “Last. After they have done it.”
Normalizing has a cost. Both say you end up with four tables and need a join to see the original sheet again.
Where the Emphasis Differs¶
Chapter |
Guide |
|
|---|---|---|
What the lesson is |
The hand procedure, done on every example. |
The worked chapter “is not the lesson.” The lesson “happens between you, the student, and the machine.” |
Where the answer comes from |
“The point of writing them down is to let the sheet tell you.” |
“That claim is not in the data.” You have to ask a person. |
Hand work |
The whole method |
Five minutes with the machine off, to build the habit |
What ends up in the student’s hands |
Correct tables and the two tests |
The two tests (“the student’s independence”) and the question “what did it assume about us?” |
Machines |
Not mentioned |
The main subject |
Claims in the Guide the Chapter Does Not Support¶
“The machine does this topic perfectly… right almost every time.” The chapter says nothing about machines. The guide also contradicts itself: in its next section it says the machine will make a choice the data cannot settle, “sound certain,” and not tell you it chose.
“The machine will pick one, it will sound certain, and it will not tell you it chose.” This is a prediction about how a model behaves, stated as fact. The chapter offers nothing to support it, and the guide’s classroom session depends on it being true.
“Only the first two of those were ever in a textbook.” The chapter is the textbook, and it already teaches the third outcome (running both tests on a design). The guide’s own companion chapter disproves this.
The five-rung ladder (Doing, Acquiring, Comprehending, Verifying, Guiding) and “the old version of this course” come from outside the chapter.
The Difference That Matters Most¶
Important
The chapter teaches students to read dependencies off the rows. The guide’s central claim is that you can’t.
The chapter’s main example of a hidden fact is homeroom: “check the rows… Every 9th grader has the same homeroom teacher. So homeroom… is about the grade.” That conclusion comes from two 9th graders. Its supporting “proof”, that changing Maria’s grade forces her homeroom to change, is a rule about how the school works, not something the sheet shows. The chapter’s warning goes further: “let the sheet tell you.”
The guide’s sentence “for the board” is the opposite: “The machine can read the table. It cannot read the world the table is about.”
This matters because the guide tells teachers to use the chapter as the reference and fallback. A student who studies it learns to read dependencies off the data, which is exactly the habit the guide is trying to break. Used together, as intended, the two pages contradict each other on the one idea the guide says the whole topic turns on.
Suggested Fix¶
The smallest fix is in the chapter, not the guide. Reword the homeroom passage along the lines of “the rows suggest homeroom is about the grade; that’s a guess until you ask the school.” That turns the chapter’s main worked example into the guide’s lesson instead of working against it.