Durbin-Watson Statistic Calculator
Detect autocorrelation in regression residuals.
Durbin-Watson Statistic
0.900000
Approx Autocorrelation0.5500
Durbin-Watson Statistic vs Sum of (et - et-1) squared
Formula
## Durbin-Watson Test **DW = Sum(et - et-1)^2 / Sum(et^2)** DW near 2 = no autocorrelation. DW < 2 = positive, DW > 2 = negative.
Exemplo Resolvido
Sum diff sq=45, sum e sq=50.
- 01DW = 0.90
- 02Positive autocorrelation
Perguntas Frequentes
Good DW value?
Close to 2 means no autocorrelation.
What causes autocorrelation?
Omitted variables or incorrect model form.
Fix?
Add lagged variables or use GLS.
Aprender