Linear regression hyperparameter tuning example. m shows the slope of the equation.

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By contrast, the values of other parameters such as coefficients of a linear model are learned. In machine learning, a hyperparameter is a parameter, such as the learning rate or choice of optimizer, which specifies details of the learning process, hence the name hyper parameter. Note. In Terminal 2, only 1 Trial of Logistic Regression was selected. The process is Nov 2, 2022 · Conclusion. May 16, 2021 · So there you have it, that’s how I do hyperparameter tuning for Lasso and Ridge. It is computed when you train the model. SyntaxError: Unexpected token < in JSON at position 4. likelihood or a cross-validation). Jul 17, 2023 · In this blog, I will demonstrate 1. This lesson delves into the concept of hyperparameters in logistic regression, highlighting their importance and the distinction from model parameters. Mar 10, 2022 · Kshitiz Regmi. This is also called tuning . For example, in healthcare, the choice of hyperparameters can affect the accuracy of medical Tuning Hyperparameters. The R-squared varies a lot from fold to fold, especially for Extreme Gradient Boosting and Multiple Linear Regression. Example: max_depth in Decision Tree, learning rate in a neural network, C and sigma in SVM Jan 11, 2023 · Linear regression is one of the simplest and most widely used algorithms in machine learning. We are ready to tune! Let’s use tune_grid() to fit models at all the different values we chose for each tuned hyperparameter. This is usually the first classification algorithm you'll try a classification task on. The core of the Data Science lifecycle is model building. Logistic Regression (aka logit, MaxEnt) classifier. There are several methods for hyperparameter tuning, including: Grid Search LogisticRegression. The above base model was performed on the original data without any normalization. Apr 6, 2023 · Without proper tuning, your model may underfit or overfit the data, resulting in poor performance. Let us usey = 5000*sin(x) as an example. Three phases of parameter tuning along feature engineering. 2) Weights or Coefficients of independent variables SVM. OneVsRestClassifier(LogisticRegressionCV()) if you still want to use OvR. linear_model. Dec 30, 2020 · The learning algorithm is continuously updating the parameter values as learning progress but hyperparameter values set by the model designer remain unchanged. This technique is able to perfectly fit any linearly dependent data. 3)Depth of tree in Decision trees. Keras Tuner is an easy-to-use, distributable hyperparameter optimization framework that solves the pain points of performing a hyperparameter search. OLS minimizes the LOLS L O L S function by β β and solution, β^ β ^, is the Best Linear Unbiased Estimator (BLUE). e. Unexpected token < in JSON at position 4. Let's demonstrate the naive approach to validation using the Iris data, which we saw in the previous section. You can tune your favorite machine learning framework ( PyTorch, XGBoost, TensorFlow and Keras, and more) by running state of the art algorithms such as Population Based Training (PBT) and HyperBand/ASHA . Hyperparameter tuning by grid-search; Hyperparameter tuning by randomized-search; 🎥 Analysis of hyperparameter search results; Analysis of hyperparameter search results; Evaluation and hyperparameter tuning; 📝 Exercise M3. In machine learning, hyperparameter tuning identifies a set of optimal hyperparameters for a learning algorithm. I hope you found it helpful, the main points again: remember to scale your variables; alpha = 0 is just the linear regression; do multiple steps when searching for the best parameter; use a squared difference based score to measure performance. Mar 26, 2024 · For example, linear regression and logistic regression are algorithms associated with statistical modeling, hyperparameter tuning in machine learning is performed by following the steps Mar 19, 2020 · An example would be to predict the rainfall of tomorrow, given the rainfall of the two previous days and today. In this article, I will demonstrate the process to tune 2 things of Neural Network: (1) the hyperparameters and (2) the layers. Using linear booster has relatively lesser parameters to tune, hence it computes much faster than gbtree booster. Cross-validate your model using k-fold cross validation. Sep 26, 2019 · Automated Hyperparameter Tuning. Variants of linear regression (ridge and lasso) have regularization as a hyperparameter. Ordinary least squares Linear Regression. 0. Nov 13, 2019 · What is hyperparameter tuning ? Hyper parameters are [ SVC(gamma=”scale”) ] the things in brackets when we are defining a classifier or a regressor or any algo. These parameters include a number of iterations, learning rate, L2 leaf regularization, and tree depth. To perform hyperparameter optimization in Regression Learner, follow these steps: Choose a model type and decide which hyperparameters to optimize. Then, when we run the hyperparameter tuning, we try all the combinations from both lists. Jun 9, 2023 · For brief explanation and more information on hyper parameter tuning you can refer this Link. Linear regression tries to find the best straight line that predicts the outcome from the features. To see all model parameters that have already been set by Scikit-Learn and its default values, we can use the get_params() method: svc. Let’s take the following values: max_depth = 5: This should be between 3-10. The number/ choice of features is not a hyperparameter, but can be viewed as a post processing or iterative tuning process. 11. Use sklearn. Apr 9, 2022 · Yet, the plethora of hyperparameters, algorithms, and optimization objectives can lead to an unending cycle of continuous optimization effort. It was initially developed by Tianqi Chen and was described by Chen and Carlos Guestrin in their 2016 paper titled “ XGBoost: A Scalable Sep 9, 2021 · linear-regression; bayesian; hyperparameters; Hyperparameter tuning with GridSearch with various parameters. how to interpret and visually explain the optimized hyperparameter space together with the model performance accuracy. Despite its simplicity, it can be quite powerful, especially when combined with proper hyperparameter tuning. the performance metrics) in order to monitor the model performance. hyperparameter tuning) An important task in ML is model selection, or using data to find the best model or parameters for a given task. How we tune hyperparameters is a question not only about which tuning methodology we use but also about how we evolve hyperparameter learning phases until we find the final and best. # start the hyperparameter search process. Since random search randomly picks a subset of hyperparameter combinations, we can afford to try more values. The simplest way of simulating such a scenario is to use a known function and check it’s behavior. Since this is a classification problem, we shall use the Logistic Regression as an example. Implementation of Random Forest Regressor using Python To implement random forest regression we will use sklearn library, which provides different set of tools for machine learning tasks. 906409322651129. In base R, you can fit one using the lmmethod. Using the MLflow REST API Directly. In the multiclass case, the training algorithm uses the one-vs-rest (OvR) scheme if the ‘multi_class’ option is set to ‘ovr’, and uses the cross-entropy loss if the ‘multi_class’ option is set to ‘multinomial’. Methods for Hyperparameter Tuning. GridSearchCV is a scikit-learn class that implements a very similar logic with less repetitive code. Our first caret example consists of fitting a simple linear regression. In the previous exercise we used one for loop for each hyperparameter to find the best combination over a fixed grid of values. target. Typical values for c and gamma are as follows. SVM Hyperparameters. print("[INFO] performing random search") searcher = RandomizedSearchCV(estimator=model, n_jobs=-1, cv=3, Predict class or regression value for X. 02; 📃 Solution for Exercise M3. Unlike many machine learning algorithms that seem to be a black box, the logisitc Nov 2, 2022 · For example, the weights learned w hile training a linear regression model are parameters, but the learning rate in gradient descent is a hyperparameter. keyboard_arrow_up. Based on the problem and how you want your model to learn, you’ll choose a different objective function. Model hyper-parameters are used to optimize the model performance. Jul 21, 2022 · Fitting Linear Regression. Before you learn how to fine-tune the hyperparameters of your machine learning model, let’s try to build a model using the classic Breast Cancer dataset that ships with sklearn. This means that you can use it with any machine learning or deep learning framework. Applying a randomized search. An Example Scenario. To let your tuning job specify the training method, you define a categorical hyperparameter named training_method with the following options: LINEAR_REGRESSION and DNN . As such, XGBoost is an algorithm, an open-source project, and a Python library. k. " Here the prefix "hyper" suggests that the parameters are top-level parameters that are used in controlling the learning process. You can see the Trial # is different for both the output. An example of hyperparameter tuning is a grid search. Tuning may be done for individual Estimator s such as LogisticRegression, or for entire Pipeline s which include multiple algorithms, featurization, and Linear regression assumes that there is an independent scalar variable and a dependent variable (actually a vector of scalar variables in the general case of multiple linear regression). datasetsimportload_irisiris=load_iris()X=iris. Many machine learning algorithms have hyperparameters that need to be set. For a regression model, the predicted value based on X is returned. What are hyperparameters? — The what Nov 21, 2022 · An Intro to Logistic Regression in Python (w/ 100+ Code Examples) The logistic regression algorithm is a probabilistic machine learning algorithm used for classification tasks. Tuning using a grid-search #. Mar 23, 2024 · Hyperparameter tuning is a critical step in optimizing machine learning models for optimal performance. First thing’s first. Linear regression is one of the most well known algorithms. The max depth for a decision tree model is a hyperparameter. 0 or a full penalty. Interpreting a decision tree should be fairly easy if you have the domain knowledge on the dataset you are working with because a leaf node will have 0 gini index because it is pure, meaning all the samples belong to one class. Indeed, my predictions were bad, and I was asked to change the hyperparameters to obtain better results. This is in contrast to parameters which determine the model itself. tuner_rs = RandomSearch(. Hyperparameter tuning, also called hyperparameter optimization, is the process of finding the configuration of hyperparameters that results in the best performance. The most commonly used are: reg:squarederror: for linear regression; reg:logistic: for logistic regression Model selection (a. Keras Tuner makes it easy to define a search Feb 9, 2022 · The GridSearchCVclass in Sklearn serves a dual purpose in tuning your model. A hyperparameter is a model argument whose value is set before the learning process begins. Orchestrating Multistep Workflows. 1. In line 4 GridSearchCV is defined as grid_lr where estimator is the machine learning model we want to use which is Logistic Regression defined as model in line 2. P. Hyperparameters can be classified as model hyperparameters, that typically cannot be inferred 3 days ago · Step 1: Fix Learning Rate and Number of Estimators for Tuning Tree-Based Parameters. If selected by the user they can be specified as explained on the tutorial page on learners – simply pass them to makeLearner(). Feb 23, 2022 · When applying Bayesian methods to ridge regression, we need to address: how do we handle the hyperparameter that controls regularization strength? One option is to use a point estimate, where a value of the hyperparameter is chosen to optimize some metric (e. Jul 29, 2020 · A practical example is a polynomial regression. Automated tuning. It is specified when you create the model. Aug 4, 2020 · Note : in the above examples are using sample datasets and models which we are using linear and logistic regression models will be explain in detail my next posts. The table of actual nearest neighbors in a KNN model is a parameter. General Hyperparameter Tuning Strategy 1. By using libraries like scikit-learn, we can directly implement logistic Sep 19, 2021 · Example: coefficients in logistic regression/linear regression, weights in a neural network, support vectors in SVM. m shows the slope of the equation. May 7, 2022 · In step 9, we use a random search for Support Vector Machine (SVM) hyperparameter tuning. S - I am new to python and machine learning, so maybe code is not very optimised or correct in some way. how to select a model that can generalize (and is not overtrained), 3. Model tuning with a grid. Jul 2, 2023 · Comparison of Non-Linear Kernel Performances; Let's learn how to implement cross validation and perform a hyperparameter tuning. If gamma is small, c affects the model just like how it affects a linear model. Hyperparameters are user-defined configuration settings that guide the learning process and drive the model to peak performance. Next we choose a model and hyperparameters. The value of the Hyperparameter is selected and set by the machine learning Jan 29, 2020 · In fact, many of today’s state-of-the-art results, such as EfficientNet, were discovered via sophisticated hyperparameter optimization algorithms. Aug 6, 2020 · The above table makes it clear why the scores obtained from the 4-fold CV differ to that of the training and validation set. Lasso regression was used extensively in the development of our Regression model. For example, if you want to tune the learning_rate and the max_depth, you need to specify all the values you think will be relevant for the search. Although relatively unsophisticated, a model called K-nearest neighbors, or KNN when acronymified, is a solid way to demonstrate the basics of the model making process …from selection, to hyperparameter optimization and finally evaluation of accuracy and precision (however, take the Tuning in tidymodels requires a resampled object created with the rsample package. One might also be skeptical of the immediate AUC score of around 0. In penalized logistic regression, we need to set the parameter C which controls regularization. 1. I am generating the data from sinc function with some Gaussian noise. Dec 7, 2023 · Linear regression is one of the simplest and most widely used algorithms in machine learning. Oct 10, 2020 · The scikit-learn Python machine learning library provides an implementation of the Ridge Regression algorithm via the Ridge class. This article will delve into the Mar 7, 2021 · Extreme Gradient Boosting, or XGBoost for short, is an efficient open-source implementation of the gradient boosting algorithm. Take for instance ExtraTreeRegressor (from extremely randomized tree regression model Jun 26, 2019 · It’s a beautiful day in the neighborhood. content_copy. Jun 12, 2020 · Elastic net is a penalized linear regression model that includes both the L1 and L2 penalties during training. Model accuracy is 0. This tutorial won’t go into the details of k-fold cross validation. There are 3 ways in scikit-learn to find the best C by cross validation. 99 by using GridSearchCV for hyperparameter tuning. XGBoost Hyperparameter tuning: XGBRegressor (XGBoost Regression) XGBoost stands for Extreme Gradient Boosting, is a scalable, distributed gradient-boosted decision tree (GBDT) machine learning library. predict(X_test) Ray Tune includes the latest hyperparameter search algorithms, integrates with TensorBoard and other analysis libraries, and natively supports distributed training through Ray’s distributed machine learning engine. Bayesian Optimization can be performed in Python using the Hyperopt library. Parameters: X {array-like, sparse matrix} of shape (n_samples, n_features) The input samples. get_params() This method displays: If the issue persists, it's likely a problem on our side. (and decision trees and random forests), these learnable parameters are how many decision variables are Oct 16, 2023 · Hyperparameter tuning also plays a pivotal role in the development of real-world applications. See Select Hyperparameters to Optimize. A model hyperparameter is a configuration that is external to the model and whose value cannot be estimated from data. 02; Quiz M3. The vector of the independent variable represents the factors that are used to compute the dependent variable or outcome. Hyperparameters are the knobs and levers that we use to adjust the training process, such as learning rate, batch size, regularization strength, and others, depending on the specific model and task at hand. For a classification model, the predicted class for each sample in X is returned. Feb 18, 2021 · In this tutorial, only the most common parameters will be included. Model validation the wrong way ¶. Hence, it's more useful on high dimensional data sets. May 14, 2021 · XGBoost is a great choice in multiple situations, including regression and classification problems. At the end of the learning process, model parameters are what constitute the model itself. Feb 21, 2023 · Hyperparameter optimization is the key to unlocking a machine learning model ‘s full potential, ensuring it performs at its best on a given task. Decision Tree Regression Decision Tree Regression builds a tree like structure by splitting the data based on the values of various features. Hyperparameter tuning can also help prevent issues like vanishing gradients, exploding gradients, and overfitting. get_params(). This example shows how to tune hyperparameters of a regression ensemble by using hyperparameter optimization in the Regression Learner app. Note that this only applies to the solver and not the cross-validation generator. Step 1 : Importing Necessary Libraries Oct 20, 2021 · Performing Classification using Logistic Regression. This increase in complexity of the structure, despite reducing errors, does not May 31, 2020 · For a linear kernel, we just need to optimize the c parameter. The main hyperparameters we may tune in logistic Aug 17, 2020 · Comparing Terminal 1 Output and Terminal 2 Output, we can see different parameters are selected for Random Forest and Logistic Regression. random_stateint, RandomState instance, default=None. It forms an equation like. Hyperparameter optimization is not supported for the models in Linear Regression Models. Hyperparameter tuning is the process of tuning a machine learning model's parameters to achieve optimal results. The class allows you to: Apply a grid search to an array of hyper-parameters, and. Utilizing an exhaustive grid search. I have used a LinearRegression (lr) to predict some values. For example, in tree-based models like XGBoost. Apr 21, 2023 · Optuna is a hyperparameter tuning library that is specifically designed to be framework agnostic. e OLS, there is none. Packaging Training Code in a Docker Environment. Parameters for Linear Booster. Jun 25, 2024 · For example, with neural networks, you decide the number of hidden layers and the number of nodes in each layer. Now, in oder to find the best parameters to for RBF kernel, I am using GridSearchCV by running 5-fold cross validation. Reproducibly run & share ML code. It involves selecting the best combination of hyperparameters, such as regularization Feb 18, 2022 · For example: The number of neighbors to inspect in a KNN model is a hyperparameter. LinearRegression (*, fit_intercept=True, normalize=False, copy_X=True, n_jobs=None) From here, we can see that hyperparameters we can adjust are fit_intercept, normalize, and n_jobs. May 14, 2018 · For standard linear regression i. Using the terminology from “ The Elements of Statistical Learning ,” a hyperparameter “ alpha ” is provided to assign how much weight is given to each of the L1 and L2 penalties. Python Package Anti-Tampering. Hyperparameter Tuning. 3) Split points in Decision Tree. get_params() Dec 21, 2021 · In line 3, the hyperparameter values are defined as a dictionary where keys are the hyperparameter name and a list of values containing hyperparameter values we want to try. fit(X_train,y_train["speed"]) y_predict_speed = model. The default value is 1. There are several options for building the object for tuning: Tune a model specification along with a recipe Nov 7, 2021 · I recently started working on Machine Learning with Linear Regression. Dec 26, 2019 · sklearn. It provides parallel tree boosting and is the leading machine learning library for regression, classification, and ranking Nov 18, 2018 · Consider the Ordinary Least Squares: LOLS =||Y −XTβ||2 L O L S = | | Y − X T β | | 2. Jul 15, 2021 · A core benefit to machine learning is its ability to discover and identify patterns and regularities in Big Data by automatically tuning many thousands or millions of “learnable” parameters. For example, if the hyperparameters include the learning rate and the number of hidden layers in a neural Jan 28, 2021 · Hyperparameter tuning is an important part of developing a machine learning model. In Terminal 1, we see only Random Forest was selected for all the trials. 2)Value of K in KNN. For example, 1)Kernel and slack in SVM. Jun 7, 2021 · Additionally, a stochastic optimization approach may also be applied for hyperparameter tuning which will automatically navigate the hyperparameter space in an algorithmic manner as a function of the loss function (i. 9. We achieved an R-squared score of 0. Used when solver='sag', ‘saga’ or ‘liblinear’ to shuffle the data. multiclass. Examples of parameters. In this tutorial, we will be using the grid search Start learning. Dec 13, 2019 · 1. The performance of a model on a dataset significantly depends on the proper tuning, i. May 17, 2021 · In this tutorial, you learned the basics of hyperparameter tuning using scikit-learn and Python. When using Automated Hyperparameter Tuning, the model hyperparameters to use are identified using techniques such as: Bayesian Optimization, Gradient Descent and Evolutionary Algorithms. Optuna offers three distinct features that make it an optimal hyperparameter optimization framework: Eager search spaces: automated search for optimal hyperparameters Apr 17, 2017 · For example, 1) Weights or Coefficients of independent variables in Linear regression model. Model with default parameters: model = XGBRegressor() model. In this article, I illustrate the importance of hyperparameter tuning by comparing the predictive power of logistic regression models with various hyperparameter values. In order to decide on boosting parameters, we need to set some initial values of other parameters. Dec 30, 2017 · I am trying to create a SV Regression. , finding the best combination of the model hyperparameters. Each function has its own parameters that can be tuned. Hyperparameter Tuning is a critical step in the machine learning pipeline that can make a significant difference in the final model's performance and generalization ability. Apr 30, 2020 · Random Search. Jan 8, 2019 · Normalization and Resampling. The decision tree has max depth and min number of observations in leaf as hyperparameters. #. In grid search, the data scientist or machine learning engineer defines a set of hyperparameter values to search over, and the algorithm tries all possible combinations of these values. c represents the constant value. In sklearn , hyperparameters are passed in as arguments to the constructor of the model classes. Let’s see how to use the GridSearchCV estimator for doing such search. x represents the x value. a. Exploring hyperparameters involves Jun 5, 2023 · Also we will learn some hyperparameter tuning techniques. Bayesian Optimization. Here, we adopt the MinMaxScaler and constrain the range of values to be between 0 and 1. We investigated hyperparameter tuning by: Obtaining a baseline accuracy on our dataset with no hyperparameter tuning — this value became our score to beat. Refresh. If gamma is large, the effect of c becomes negligible. Mar 15, 2023 · For example, the weights learned while training a linear regression model are parameters, but the learning rate in gradient descent is a hyperparameter. how to learn a boosted decision tree regression model with optimized hyperparameters using Bayesian optimization, 2. In caret, you can do the same using: lm_model <- train(mpg ~ hp + wt + gear + disp, data = mtcars_train, method = "lm") Jul 9, 2024 · For example, you could define a hyperparameter tuning job with the goal of finding an optimal model using either linear regression or a deep neural network (DNN). Exemple: Here is an example of Python code that performs Hyperparameter Tuning on a linear regression model using GridSearchCV from the sklearn library. Aug 28, 2021 · The basic way to perform hyperparameter tuning is to try all the possible combinations of parameters. As the name suggests, this hyperparameter tuning method randomly tries a combination of hyperparameters from a given search space. 02; 🏁 Wrap-up quiz 3; Main take-away; Linear models Feb 16, 2019 · A hyperparameter is a parameter whose value is set before the learning process begins. It controls L1 regularization (equivalent to Lasso regression) on weights. In this tutorial, we will show you how to integrate Ray Tune into your PyTorch training workflow. LinearRegression fits a linear model with coefficients w = (w1, …, wp) to minimize the residual sum of squares between the observed targets in the dataset, and the targets predicted Tune is a Python library for experiment execution and hyperparameter tuning at any scale. Discover various techniques for finding the optimal hyperparameters The answer is, " Hyperparameters are defined as the parameters that are explicitly defined by the user to control the learning process. Jul 6, 2024 · y = mx + c. So, the linear regression model takes the data with x or input values and y or output values and calculates the m/slope and the constant. Jul 9, 2024 · Hyperparameter tuning overview. Below, you can find a number of tutorials and examples for various MLflow use cases. I used the following command to obtain the hyperparameters: lr. Simply it creates different subsets of data. Explore and run machine learning code with Kaggle Notebooks | Using data from California Housing Prices. However, if we want to use an RBF kernel, both c and gamma parameter need to optimized simultaneously. Build a grid search for tuning hyperparameters. keys() lr. . My code: Jun 13, 2024 · Hyperparameter-tuning is important to find the possible best sets of hyperparameters to build the model from a specific dataset. However, by construction, ML algorithms are biased which is also why they perform good. For instance, LASSO only have a different Tutorials and Examples. Logistic regression finds the best possible fit between the predictor and target variables to predict the probability of the target variable belonging to a labeled class/category. Model performance depends heavily on hyperparameters. Hyperparameters: Vanilla linear regression does not have any hyperparameters. In the above equations: Y represents the continuous output value. Oct 31, 2021 · I'm trying to do some hyperparameter tuning with RandomizedSeachCV, and the performance of the model with the best parameters is worse than the one of the model with the default parameters. Confusingly, the lambda term can be configured via the “ alpha ” argument when defining the class. I find it more difficult to find the latter tutorials than the former. To use this method in keras tuner, let’s define a tuner using one of the available Tuners. Alpha is a value between 0 and 1 and is used to Unlike linear regression, which predicts continuous outcomes, logistic regression is used to predict binary outcomes. Tune further integrates with a wide range of Nov 11, 2019 · The best way to tune this is to plot the decision tree and look into the gini index. Often suitable parameter values are not obvious and it is preferable to tune the hyperparameters, that is May 31, 2021 · of hyperparameters defined we can kick off the hyperparameter tuning process: # initialize a random search with a 3-fold cross-validation and then. It covers the significance of hyperparameter tuning and introduces GridSearchCV, a tool in sklearn for optimizing hyperparameters systematically. Here’s a full list of Tuners. Some examples of hyperparameters include penalty in logistic regression and loss in stochastic gradient descent. In addition to shrinkage, enabling alpha also results in feature selection. We will start by loading the data: In [1]: fromsklearn. Apr 12, 2021 · Hyperparameter Tuning. Compare the test set performance of the trained optimizable ensemble to that of the best-performing preset ensemble model. g. This post is about the differences between LogisticRegressionCV, GridSearchCV and cross_val_score. For more information on Decision tree Regression you can refer to this blog by Ashwin Prasad - Link. datay=iris. LinearRegression(*, fit_intercept=True, copy_X=True, n_jobs=None, positive=False) [source] #. Consider the following setup: StratifiedKFold, cross_val_score. The coefficients (or weights) of linear and logistic regression models. If we look at the generating code and the plot, it would look like below. Nov 10, 2023 · Creating high-performance machine learning (ML) solutions relies on exploring and optimizing training parameters, also known as hyperparameters. If you want to discover more hyperparameter tuning possibilities, check out the CatBoost documentation here. Normalization class sklearn. eq xs pf pz xs hj bs xw au vk