Proportion explained variance in Watson OpenScale quality metrics

Proportion explained variance at a glance

• Description: Proportion explained variance is the ratio of explained variance and target variance. Explained variance is the difference between target variance and variance of prediction error.
• Default thresholds: Lower limit = 80%
• Default recommendation:
  • Upward trend: An upward trend indicates that the metric is improving. This means that model retraining is effective.
  • Downward trend: A downward trend indicates that the metric is deteriorating. Feedback data is becoming significantly different than the training data.
  • Erratic or irregular variation: An erratic or irregular variation indicates that the feedback data is not consistent between evaluations. Increase the minimum sample size for the Quality monitor.
• Problem type: Regression
• Chart values: Last value in the timeframe
• Metrics details available: None

Do the math

The Proportion explained variance is calculated by averaging the numbers, then for each number, subtract the mean, and square the results. Then, work out the squares.

                                  sum of squares between groups 
Proportion explained variance =  ________________________________

                                      sum of squares total

Learn more

Reviewing quality results

Parent topic: Quality metrics overview