color{#6A5ACD}{Y_i}\)` changes as we look at different values of `\(x_{0}\)`.
- Only a statement about the data, not about the reasons behind the pattern.

.hi-purple[**Prediction:**] Model does **not** need to be interpretable.
- Coefficients `\(\beta\)` are informative only of predictive power, not causal effects.
- `\(\color{#e64173}{\beta_0}\)` might reflect the treatment effect of `\(x_{0}\)`, *or* the effects of omitted variables for which `\(x_0\)` happens to be a good proxy.
- Generally, the model c