Examples
Examples
Try the starting example
- Observed weights: date, kg
- 2026-10-01,5 2026-10-11,5.2 2026-10-21,5.4
- Display window start date
- 2026-10-01
- Display window end date
- 2026-10-21
- Latest observed weight (kg)
- 5.4
- Last minus first observed weight (kg)
- 0.4
- Least-squares slope (kg/day)
- 0.02
- Measurements included
- 3
Try another scenario
- Observed weights: date, kg
- 2026-10-01,5 2026-10-11,5.2 2026-10-21,5.4
- Display window start date
- 2026-10-11
- Display window end date
- 2026-10-21
- Latest observed weight (kg)
- 5.4
- Last minus first observed weight (kg)
- 0.2
- Least-squares slope (kg/day)
- 0.02
- Measurements included
- 2
Calculation method
Calculation method
Latest observed weight (kg)
Use the last dated observation inside the inclusive display window.
Last minus first observed weight (kg)
Subtract first from last observation; this is an observed difference, not a fitted prediction.
Least-squares slope (kg/day)
Fit weight=a+b×days with an intercept: b=Σ((x−mean x)(y−mean y))/Σ((x−mean x)²). Days are centred near the first included date.
Measurements included
Count distinct-date measurements within the selected window; at least two are required.
Symbols and units
- a
- Observed weights: date, kg
- b
- Display window start date
- c
- Display window end date
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- An observational dated-weight summary, with no diagnosis, target weight, feeding recommendation or future-weight forecast. Measurement consistency and clinical interpretation require separate assessment.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
NIST: linear least-squares regression ↗
Background reading; this does not imply endorsement or independent review of SumFizz.