Contents

- 1 What is regret in online learning?
- 2 What is regret in machine learning?
- 3 What is regret in reinforcement learning?
- 4 What is no regret learning?
- 5 What is batch learning?
- 6 What is a regret bound?
- 7 What is online learning machine learning?
- 8 What is counterfactual regret?
- 9 What is Sublinear regret?
- 10 Why do we need to balance exploration and exploitation in Q learning?
- 11 What is the importance of exploration in RL?
- 12 What is Epsilon in reinforcement learning?

## What is regret in online learning?

A popular criterion in online learning is. regret minimization. Regret is defined as the difference between the reward that could have been achieved, given the choices of the opponent, and what was actually achieved.

## What is regret in machine learning?

Mehryar Mohri – Introduction to Machine Learning. Regret. Definition: the regret at time is the difference. between the loss incurred up to by the algorithm.

## What is regret in reinforcement learning?

Regret in Reinforcement Learning So we define the regret L, over the course of T attempts, as the difference between the reward generated by the optimal action a* multiplied by T, and the sum from 1 to T of each reward of an arbitrary action.

## What is no regret learning?

A learning algorithm is said to exhibit no – regret iff average payoffs that are achieved by the algorithm exceed the payoffs that could be achieved by any fixed strategy in the limit.

## What is batch learning?

In batch learning the machine learning model is trained using the entire dataset that is available at a certain point in time. Once we have a model that performs well on the test set, the model is shipped for production and thus learning ends. This process is also called offline learning.

## What is a regret bound?

A regret bound measures the performance of an online algorithm relative to the performance of a competing prediction mechanism, called a competing hypothesis.”

## What is online learning machine learning?

In computer science, online machine learning is a method of machine learning in which data becomes available in a sequential order and is used to update the best predictor for future data at each step, as opposed to batch learning techniques which generate the best predictor by learning on the entire training data set

## What is counterfactual regret?

Counterfactual Regret Minimization (CFR) is a popular, iterative algorithm for computing strategies in extensive-form games. The Monte Carlo CFR (MCCFR) variants reduce the per iteration time cost of CFR by traversing a smaller, sampled portion of the tree.

## What is Sublinear regret?

1 Recap of Multi-armed bandits Finally, we looked at a frequentist algorithm, the upper confidence bounds (UCB) algorithm, which is ”opti- mal’ in the sense that it achieves a sublinear regret, meaning that it learns and makes a decreasing number of mistakes as time grows.

## Why do we need to balance exploration and exploitation in Q learning?

Balancing the ratio of exploration and exploitation is an important problem in reinforcement learning [1]. The agent can choose to explore its environment and try new actions in search for better ones to be adopted in the future, or exploit already tested actions and adopt them.

## What is the importance of exploration in RL?

A classical approach to any reinforcement learning ( RL ) problem is to explore and to exploit. Explore the most rewarding way that reaches the target and keep on exploiting a certain action; exploration is hard. Without proper reward functions, the algorithms can end up chasing their own tails to eternity.

## What is Epsilon in reinforcement learning?

Reinforcement learning is a subtype of artificial intelligence which is based on the idea that a computer learn as humans do — through trial and error. It aims for computers to learn and improve from experience rather than being explicitly instructed.