Chapter 4 VI.4
Identification
Identification asks whether an interventional quantity can be written in terms of observed ones, and the graph answers it.
Whether an interventional quantity can be written in observed ones.
How this chapter is built
M3Load-bearing
The content is mathematics. Understanding is demonstrated by computation, not recall.
Five strands, not one. Mathematics is the spine; the other four are the body. A chapter cannot pay its way out of teaching with problems, nor out of problems with teaching.
Before you start
The problem
An experiment is often impossible. The question then is whether the effect is recoverable from observation at all — a question with a yes-or-no answer that depends on the graph and not on the sample size.
What this chapter covers
- Backdoor criterion
- Adjustment
- Front-door criterion
- Conditional independence
Apparatus
The mathematics this chapter leans on, held in Book 0 so it can be assumed here without being taught here. Not a gate — follow a link when a step stops making sense.
Bayes' rule 0.PR.04 · Conditional independence 0.PR.05 · Estimators, bias and variance 0.ST.01
Notation
- do(·)The intervention operator
- X (random)A random variable
- 𝔼Expectation
- VarVariance
Propositions
Not yet written. The topics above are the plan for this chapter; each will become a proposition with its own figure.
Worked problems
0/5 problems0/4 variants0/10 exercisesowes 15 more
Not yet written. At M3 this chapter owes 5 worked problems across 4 distinct variants, and 10 exercises, every one with a published solution. The build enforces that from the day the chapter is marked published.