Why Reparameterization is Not Enough

Oct 13, 2025 by wbrum.org 132 views

How to Avoid Randomness While Validating: A Guide to Stationary Results

In the realm of machine learning, randomness is often used to introduce variability and prevent overfitting. However, when it comes to validation, randomness can be a double-edged sword. While it may help to identify the best model or hyperparameters, it can also lead to non-stationary results, making it difficult to compare and evaluate different models. In this article, we will explore the concept of randomness in validation and provide guidance on how to avoid it, ensuring that your results are stationary and reliable.

Randomness in validation is often introduced through the use of normal distributions or other probabilistic methods. For example, in the SocialCircle and Re models, normal distributions are used to describe randomness. However, as you pointed out, the validation results may not be stationary, and some epochs may perform better than others. This can be attributed to the randomness introduced during training, which can lead to non-stationary results.

The Problem with Non-Stationary Results

Non-stationary results can make it challenging to compare and evaluate different models. When testing with methods that introduce randomness, such as AgentFormer or PGP, it can be difficult to determine whether the SOTA (state-of-the-art) epoch was brought by the randomness or not. This can lead to confusion and make it difficult to draw meaningful conclusions from your results.

Why Reparameterization is Not Enough

Reparameterization is a technique used to introduce randomness during training while maintaining the ability to compute gradients. However, when validating or testing, simply using the mean instead of sampling from a Gaussian distribution may not be enough to avoid randomness. This is because the mean can still be influenced by the randomness introduced during training, leading to non-stationary results.

How to Avoid Randomness While Validating

So, how can you avoid randomness while validating? Here are some strategies to help you achieve stationary results:

1. Use a Fixed Seed

Using a fixed seed for your random number generator can help to introduce a consistent level of randomness during training and validation. This can help to ensure that your results are stationary and reliable.

2. Use a Deterministic Model

Using a deterministic model, such as a neural network with a fixed architecture and weights, can help to avoid randomness altogether. However, this may limit the ability to introduce variability and prevent overfitting.

3. Use a Stationary Distribution

Using a stationary distribution, such as a uniform distribution, can help to introduce a consistent level of randomness during training and validation. This can help to ensure that your results are stationary and reliable.

4. Use a Validation Set with a Fixed Size

Using a validation set with a fixed size can help to ensure that your results are stationary and reliable. This can help to prevent overfitting and ensure that your model is generalizable to new data.

5. Use a Model with a Fixed Architecture

Using a model with a fixed architecture can help to avoid randomness altogether. This can help to ensure that your results are stationary and reliable.

In conclusion, randomness can be a double-edged sword in validation. While it may help to identify the best model or hyperparameters, it can also lead to non-stationary results, making it difficult to compare and evaluate different models. By using a fixed seed, a deterministic model, a stationary distribution, a validation set with a fixed size, and a model with a fixed architecture, you can help to avoid randomness while validating and ensure that your results are stationary and reliable.

Based on the discussion above, we recommend the following for future work:

Investigate the use of fixed seeds for random number generators: This can help to introduce a consistent level of randomness during training and validation.
Explore the use of deterministic models: This can help to avoid randomness altogether and ensure that results are stationary and reliable.
Develop new methods for introducing randomness during training: This can help to prevent overfitting and ensure that models are generalizable to new data.
Investigate the use of stationary distributions: This can help to introduce a consistent level of randomness during training and validation.
Develop new methods for evaluating model performance: This can help to ensure that results are stationary and reliable and that models are generalizable to new data.

The discussion above highlights the importance of avoiding randomness while validating. Future work should focus on developing new methods for introducing randomness during training, evaluating model performance, and ensuring that results are stationary and reliable. By doing so, we can help to ensure that machine learning models are generalizable to new data and that results are reliable and trustworthy.
Q&A: Avoiding Randomness While Validating

In our previous article, we discussed the importance of avoiding randomness while validating machine learning models. We explored the concept of randomness in validation, the problem with non-stationary results, and strategies for avoiding randomness. In this article, we will answer some frequently asked questions (FAQs) related to avoiding randomness while validating.

Q: What is the main problem with randomness in validation?

A: The main problem with randomness in validation is that it can lead to non-stationary results, making it difficult to compare and evaluate different models. When testing with methods that introduce randomness, such as AgentFormer or PGP, it can be challenging to determine whether the SOTA (state-of-the-art) epoch was brought by the randomness or not.

Q: How can I introduce randomness during training while maintaining the ability to compute gradients?

A: You can use reparameterization to introduce randomness during training while maintaining the ability to compute gradients. Reparameterization involves transforming a random variable into a differentiable function of the input variables.

Q: What is the difference between a fixed seed and a deterministic model?

A: A fixed seed is a value used to initialize a random number generator, ensuring that the same sequence of random numbers is generated every time. A deterministic model, on the other hand, is a model that always produces the same output for a given input, without any randomness.

Q: Can I use a stationary distribution to introduce randomness during training?

A: Yes, you can use a stationary distribution, such as a uniform distribution, to introduce randomness during training. This can help to ensure that your results are stationary and reliable.

Q: How can I ensure that my validation set is representative of the data?

A: You can ensure that your validation set is representative of the data by using a validation set with a fixed size and by sampling from the entire dataset. This can help to prevent overfitting and ensure that your model is generalizable to new data.

Q: Can I use a model with a fixed architecture to avoid randomness?

A: Yes, you can use a model with a fixed architecture to avoid randomness. This can help to ensure that your results are stationary and reliable.

Q: What are some common pitfalls to avoid when trying to avoid randomness while validating?

A: Some common pitfalls to avoid when trying to avoid randomness while validating include:

Using a fixed seed without ensuring that the same sequence of random numbers is generated every time.
Using a deterministic model without ensuring that the model is generalizable to new data.
Using a stationary distribution without ensuring that the distribution is representative of the data.
Using a validation set with a fixed size without ensuring that the set is representative of the data.

In conclusion, avoiding randomness while validating is crucial for ensuring that machine learning models are generalizable to new data and that results are reliable and trustworthy. By using a fixed seed, a deterministic model, a stationary distribution, a validation set with a fixed size, and a model with a fixed architecture, you can help to avoid randomness while validating. Remember to avoid common pitfalls, such as using a fixed seed without ensuring that the same sequence of random numbers is generated every time, and using a deterministic model without ensuring that the model is generalizable to new data.

Based on the discussion above, we recommend the following for future work:

Investigate the use of fixed seeds for random number generators: This can help to introduce a consistent level of randomness during training and validation.
Explore the use of deterministic models: This can help to avoid randomness altogether and ensure that results are stationary and reliable.
Develop new methods for introducing randomness during training: This can help to prevent overfitting and ensure that models are generalizable to new data.
Investigate the use of stationary distributions: This can help to introduce a consistent level of randomness during training and validation.
Develop new methods for evaluating model performance: This can help to ensure that results are stationary and reliable and that models are generalizable to new data.