Introduction
In this article, we will discuss Vertex AI Vizier. We will see how it works and how it is different from custom training, we will be discussing Vertex AI Vizer in detail along with its functionality.
Vertex AI Vizier overview
Vertex AI Vizier is a black-box optimization service that can optimize hyperparameters for complex machine learning (ML) models. If your ML model contains different hyperparameters, tuning them manually can be difficult and time-consuming. Vertex AI Vizier optimizes the output of your model by optimizing the hyperparameters.
A black box optimization is an optimization of a system that meets one of the following criteria:
- No known objective function to evaluate.
- Systems are usually too complex to be evaluated using an objective function.
Additional Vertex AI Vizier functionality
Vertex AI Vizier optimizes hyperparameters for ML models, but can also perform other optimization tasks.
Tune parameters
Vertex AI Vizier can be used to effectively tune function parameters. For example, a subscribe button on a news site can be used to determine the most effective combination of background color and link color font size. See use cases for more examples.
Read more about the difference between parameters and hyperparameters.
Optimize any evaluable system
Vertex AI Vizier works with any system that can be evaluated, including systems that cannot be expressed as closed-form analytical functions. For example, you can use Vertex AI Vizier to determine the optimal neural network depth, width, and learning rate for your TensorFlow model.
How Vertex AI Vizier works
The following sections define the terms, behaviors, and possible values you can use in Vertex AI Vizier to optimize your Machine Learning model or function. Start by defining your study configuration.
Study configurations
A study configuration is a definition of an optimization problem that you are trying to solve. It contains the results of the optimization and the hyperparameters or parameters that affect the results.
Studies and trials
A study is an implementation of a study configuration. A study uses the goals (metrics) and input values (hyperparameters or parameters) of the study configuration to perform an experiment called a trial. A trial is a set of specific input values that produces measurement results related to a goal.
Vertex AI Vizier suggests input values to use for each experiment but does not run the experiment. The
exam will continue until the specified number of trials is reached or the exam is paused. The trial will continue until you indicate that it is complete or infeasible.
Measurements
The measured value is the measurement result of the experiment. Each measurement can contain one or more metrics, and each experiment can contain one or more measurements collected over a period of time. You can add new measurements to your experiment at any time before you complete the experiment.
Search algorithms
If you don't specify an algorithm, Vertex AI Vizier will use a default algorithm. The default algorithm applies Bayesian optimization to more efficiently search the parameter space to reach the optimal solution.
The following values are available:
-
ALGORITHM_UNSPECIFIED: Same as no algorithm specified. Vertex AI chooses the best search algorithm from Gaussian process bandit, linear combination search, or their variants.
-
GRID_SEARCH: Simple grid search within the allowed space. This option is useful for specifying more attempts than the number of points in the space allowed. In such cases, the default algorithm may generate duplicate candidates if no grid search is specified. To use grid search, all parameters must be of type INTEGER, CATEGORICAL, or DISCRETE.
- RANDOM_SEARCH: A simple random search within the allowed range.
How Vertex AI Vizier differs from custom training
Vertex AI Vizier is an independent service for optimizing complex models with different parameters. It can be used for both Machine Learning and non-Machine Learning use cases. It can be used in training jobs or other systems (even multi-cloud). Custom training hyperparameter tuning is a built-in feature that VertexAIVizier uses for training jobs. It helps you determine the best hyperparameter settings for your ML model.
Use cases
Vertex AI helps Vizier fine-tune hyperparameters to optimize models or fine-tune parameters to optimize results in the following scenarios:
- Optimize the batch size, learning rate, and other hyperparameters of the neural network recommendation engine.
- Test different layouts of user interface elements to optimize the usability of your application.
- Minimize the computational resources of a job by determining the ideal buffer size and number of threads.
- Optimize the amount of ingredients in recipes to create the tastiest version.
Read about Batch Operating System here.





