Logistic Regression Report
Data, Method, and Model
| Number of cases used in the analysis | 23 |
| Number of incomplete (omitted) cases | 0 |
| Link Function | logit |
| Model | cbind(damaged, undamaged) ~ temperature |
Response Information
| Variable | Value | Count |
|---|---|---|
| damaged | Damaged O-ring | 11 |
| Undamaged O-ring | 127 | |
| trial_var | Total | 138 |
Parameter Estimates
Model: cbind(damaged, undamaged) ~ temperature
Event = Damaged O-ring
| Term | Coefficient | Standard Error | Z-Value | P-Value |
|---|---|---|---|---|
| (Intercept) | 11.663 | 3.296 | 3.538 | 0.0004028 |
| temperature | -0.21623 | 0.05318 | -4.066 | 4.777e-05 |
Odds Ratios
Model: cbind(damaged, undamaged) ~ temperature
Event = Damaged O-ring
| Term | Change | Odds Ratio | 2.5% Lower CL | 97.5% Upper CL |
|---|---|---|---|---|
| temperature | 1 | 0.8055 | 0.7258 | 0.894 |
Measures of Model Fit
Model: cbind(damaged, undamaged) ~ temperature
Event = Damaged O-ring
| Measure | Value | df |
|---|---|---|
| Deviance* | 16.9123 | 21 |
| Null Deviance** | 38.8977 | 22 |
| Log Likelihood | -14.8374 | 2 |
| MSE (Brier Score) | 0.00913606 | |
| R-Squared | 56.52% | |
| Adj R-Squared | 54.45% | |
| AIC | 33.6748 | |
| BIC | 35.9458 |
* Deviance for the specified model.
** Deviance for the intercept-only model.
Goodness-of-Fit Tests
| Test | DF | Chi-Square | P-Value |
|---|---|---|---|
| Deviance | 21 | 16.9123 | 0.7164 |
| Pearson | 21 | 28.0674 | 0.1383 |
| Hosmer-Lemeshow* | 6 | 7.38052 | 0.2871 |
* Number of groups used for the Hosmer Lemeshow test = 8
Confusions Matrix
Event = Damaged O-ring; Classification Cutoff = 0.5
| Actual | Predicted Damaged O-ring | Predicted Undamaged O-ring | Total |
|---|---|---|---|
| Damaged O-ring | 5 (3.62%) | 6 (4.35%) | 11 (7.97%) |
| Undamaged O-ring | 1 (0.725%) | 126 (91.3%) | 127 (92%) |
| Total | 6 (4.35%) | 132 (95.7%) | 138 (100%) |
ROC Plot and Cost Function Plot
