TruncationSelectionPolicy Class
Defines an early termination policy that cancels a given percentage of runs at each evaluation interval.
Initialize a TruncationSelectionPolicy.
- Inheritance
-
azureml.train.hyperdrive.policy.EarlyTerminationPolicyTruncationSelectionPolicy
Constructor
TruncationSelectionPolicy(truncation_percentage, evaluation_interval=1, delay_evaluation=0)
Parameters
Name | Description |
---|---|
truncation_percentage
Required
|
The percentage of runs to cancel at each evaluation interval. |
evaluation_interval
|
The frequency for applying the policy. Default value: 1
|
delay_evaluation
|
The number of intervals for which to delay the first policy evaluation.
If specified, the policy applies every multiple of Default value: 0
|
truncation_percentage
Required
|
The percentage of runs to cancel at each evaluation interval. |
evaluation_interval
Required
|
The frequency for applying the policy. |
delay_evaluation
Required
|
The number of intervals for which to delay the first policy evaluation.
If specified, the policy applies every multiple of |
Remarks
This policy periodically cancels the given percentage of runs that rank the lowest for their performance on the primary metric. The policy strives for fairness in ranking the runs by accounting for improving model performance with training time. When ranking a relatively young run, the policy uses the corresponding (and earlier) performance of older runs for comparison. Therefore, runs aren't terminated for having a lower performance because they have run for less time than other runs.
The Truncation Selection policy takes the following configuration parameters:
truncation_percentage
: The percentage of lowest performing runs to terminate at each evaluation interval.evaluation_interval
: The frequency for applying the policy. Each time the training script logs the primary metric counts as one interval.delay_evaluation
: The number of intervals to delay policy evaluation. Use this parameter to avoid premature termination of training runs. If specified, the policy applies every multiple ofevaluation_interval
that is greater than or equal todelay_evaluation
.
For example, when evaluating a run at a interval N, its performance is only compared with the performance of other runs up to interval N even if they reported metrics for intervals greater than N.
Attributes
delay_evaluation
Return the value for number of sequences the first evaluation is delayed.
Returns
Type | Description |
---|---|
The delay evaluation. |
evaluation_interval
truncation_percentage
POLICY_NAME
POLICY_NAME = 'TruncationSelection'