Weighted Linear Regression Calculator
Fit an intercept and slope by positive weighted least squares and predict at an entered x.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Center both variables using the same normalized positive weights to fit one line.
Slope=Σw(x−x̄w)(y−ȳw)/Σw(x−x̄w)²; intercept=ȳw−slope x̄w
Worked example
Responses 1,3,5 at x0,1,2 lie on y=1+2x for any positive weights.
Assumptions and input details
Weights are relative inverse-variance-style weights, not replicate frequencies. No uncertainty interval, robust covariance, causal model or automatic extrapolation validity. Predictor must vary.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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