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How does a GBM work?

How does a GBM work?

A Gradient Boosting Machine or GBM combines the predictions from multiple decision trees to generate the final predictions. Keep in mind that all the weak learners in a gradient boosting machine are decision trees.

Why is XGBoost faster than GBM?

XGBoost is more regularized form of Gradient Boosting. XGBoost uses advanced regularization (L1 & L2), which improves model generalization capabilities. XGBoost delivers high performance as compared to Gradient Boosting. Its training is very fast and can be parallelized / distributed across clusters.

What is the difference between GBM and XGBoost?

There has been only a slight increase in accuracy and auc score by applying Light GBM over XGBOOST but there is a significant difference in the execution time for the training procedure. Light GBM is almost 7 times faster than XGBOOST and is a much better approach when dealing with large datasets.

What problems is gradient boosting good for?

i) Gradient Boosting Algorithm is generally used when we want to decrease the Bias error. ii) Gradient Boosting Algorithm can be used in regression as well as classification problems. In regression problems, the cost function is MSE whereas, in classification problems, the cost function is Log-Loss.

What is shrinkage in GBM?

In the context of GBMs, shrinkage is used for reducing, or shrinking, the impact of each additional fitted base-learner (tree). It reduces the size of incremental steps and thus penalizes the importance of each consecutive iteration.

Why LightGBM is fast?

There are three reasons why LightGBM is fast: Histogram based splitting. Gradient-based One-Side Sampling (GOSS) Exclusive Feature Bundling (EFB)

Does LightGBM use gradient descent?

LightGBM is a gradient boosting framework based on decision trees to increases the efficiency of the model and reduces memory usage. Gradient-based One Side Sampling Technique for LightGBM: Different data instances have varied roles in the computation of information gain.

Can boosting be used for regression?

Gradient boosting can be used for regression and classification problems.

How can I speed up my gradient boosting?

To accelerate the gradient-boosting algorithm, one could reduce the number of splits to be evaluated. As a consequence, the generalization performance of such a tree would be reduced. However, since we are combining several trees in a gradient-boosting, we can add more estimators to overcome this issue.

How can you improve the performance of gradient boosting Regressor?

General Approach for Parameter Tuning

  1. Choose a relatively high learning rate.
  2. Determine the optimum number of trees for this learning rate.
  3. Tune tree-specific parameters for decided learning rate and number of trees.
  4. Lower the learning rate and increase the estimators proportionally to get more robust models.

What is an example of a stop loss order?

For example, a trader may buy a stock and places a stop-loss order 10% below the purchase price. Should the stock drop, the stop-loss order would be activated, and the stock would be sold as a market order.

Do stop-loss orders work in a rapidly moving market?

Therefore, in a rapidly moving market, a stop-loss order may not be filled at exactly the specified stop price level, but will usually be filled fairly close to the specified stop price. But traders should clearly understand that in some extreme instances stop-loss orders may not provide much protection.

What is a buy stop order?

In a buy stop order, the stop price is set above the current market price. Investors may further enhance the efficacy of their stop-loss order by combining it with a trailing stop.

What is the guarantee if a stop-loss order is triggered?

The only guarantee if a stop-loss order is triggered is that the order will be immediately executed, and filled at the prevailing market price at that time.