In this chapter you will learn the basics of applying logistic regression and support vector machines (SVMs) to classification problems. You'll use the <code>scikit-learn</code> library to fit classification models to real data.

Revisão de scikit-learn

Classificação com KNN

Comparando modelos

Overfitting

Aplicando regressão logística e SVM

Executando LogisticRegression e SVC

Análise de sentimento para críticas de filmes

Classificadores lineares

Qual fronteira de decisão é linear?

Visualizando fronteiras de decisão

Applying logistic regression and SVM

In this chapter you will discover the conceptual framework behind logistic regression and SVMs. This will let you delve deeper into the inner workings of these models.

Linear classifiers: the coefficients

How models make predictions

Changing the model coefficients

What is a loss function?

The 0-1 loss

Minimizing a loss function

Loss function diagrams

Classification loss functions

Comparing the logistic and hinge losses

Implementing logistic regression

Loss functions

In this chapter you will delve into the details of logistic regression. You'll learn all about regularization and how to interpret model output.

Logistic regression and regularization

Regularized logistic regression

Logistic regression and feature selection

Identifying the most positive and negative words

Logistic regression and probabilities

Getting class probabilities

Regularization and probabilities

Visualizing easy and difficult examples

Multi-class logistic regression

Counting the coefficients

Fitting multi-class logistic regression

Visualizing multi-class logistic regression

One-vs-rest SVM

Logistic regression

In this chapter you will learn all about the details of support vector machines. You'll learn about tuning hyperparameters for these models and using kernels to fit non-linear decision boundaries.

Support vectors

Support vector definition

Effect of removing examples

Kernel SVMs

GridSearchCV warm-up

Jointly tuning gamma and C with GridSearchCV

Comparing logistic regression and SVM (and beyond)

An advantage of SVMs

An advantage of logistic regression

Using SGDClassifier

Conclusion

Support Vector Machines

Neste curso, você vai aprender a usar classificadores lineares — especificamente regressão logística e máquinas de vetores de suporte (SVM) — com scikit-learn. Depois de ver como aplicar esses métodos, você vai explorar as ideias por trás deles e entender o que realmente faz tudo funcionar. Ao final, você saberá treinar, testar e ajustar esses classificadores lineares em Python. Também terá uma base conceitual para entender muitos outros algoritmos de Machine Learning.

Supervised Learning with scikit-learn

Neste curso, você aprenderá sobre classificadores lineares como regressão logística e SVM.

Classificadores Lineares em Python

Neste curso, você aprenderá os detalhes dos classificadores lineares, como regressão logística e SVM.

Cientista de machine learning em Python

Aprendizado de máquina supervisionado em Python

Comparando modelos

Classificadores Lineares em Python

exercicio interativo prático