The simplest baseline rule repeats the last observed value. The lesson treats that as a deterministic formula output, not as evidence about what comes later.
highlighted = computed this step
Last-value rule
The naive rule repeats the last observed value, 8. Motivation: a carry-forward baseline gives a simple reference point before any smoothing choices are introduced.
naive output=xlast=8
Next formula output
For period 7, the rule outputs 8. Why: no new data is used; the rule copies the last observed value exactly.
x^7=8
Baseline mechanic
Interpretation: the baseline is easy to audit because one input controls the output. That transparency is useful, but it is still not validation.
computed output is not validation
Diagram note
Honesty note: These values are exact formula outputs on the pinned integer series; they do not validate what happens later. Pixel positions are rounded for layout; every number shown is exact.