Equation 4 · Part 10 · How Mechanistic Interpretability Research Is Actually Done
addition
addition
What this part means
Add the term after the plus sign to the term or group before it.
Its job in the formula
Add the term after the plus sign to the term or group before it.
Full expression→addition→Article meaning
The passage around this formula
The first concrete operation in almost any interpretability project is the least glamorous: run the model forward on a batch of inputs, and at some chosen point in the computation — a residual-stream position, an attention head’s output, a particular MLP layer — copy the activation tensor out before it is overwritten by the next step of the forward pass. This is extraction, and it produces nothing on its own beyond a large table of vectors. What turns it into evidence is probing: fitting a small, separately trained classifier to predict some property of interest directly from those vectors, while the model’s own weights stay frozen. Formally, for an activation read out at layer …
Learn the underlying idea
Addition combines quantities; subtraction measures the signed difference between them. Parentheses show what is combined before the rest of the expression is evaluated.
Open the illustrated addition and subtraction in an equation guide →
Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.