CISC482 - Lecture13

Regression Practice

Dr. Jeremy Castagno

Class Business

Schedule

  • Reading 6-1: Mar 08 @ 12PM, Wednesday
  • HW4 - Mar 08 @ Midnight
  • Proposal: Mar 22, Wednesday

Today

  • Review Linear Regression
  • Review Logistic Regression
  • Practice Problems

Review Linear Regression

Give me the function models

  • Simple Linear Regression
    • \(\hat{y} = \beta_0 + \beta_1 x\)
  • Simple Polynomial Linear Regression
    • \(\hat{y} = \beta_0 + \beta_1 x + ... + \beta_k x^k\)
  • Multiple Linear Regression
    • \(\hat{y} = \beta_0 + \beta_1 x_1 + ... \beta_k x_k\)
  • Multiple (Variable) Polynomial Regression
    • \(\hat{y} = \beta_0 + \beta_1 x_1 + \beta_2 x_1^2 + \beta_3 x_1 x_2 + \beta_4 x_2 + \beta_5 x_2^2\)

Review Logistic Regression

Logistic Regression

  • We often use logistic regression for classification problems? Then why do we call it logistic regression? What is being regressed?
  • What is the function for logistic regression?
    • \(\hat{p}(x) = \frac{e^{\beta_0 + \beta_1 x}}{1+ e^{\beta_0 + \beta_1 x}}\)
  • What do we call this non-linear function? HINT - what shape does it make?

Why not Linear Regression?

  • Linear Regression is strongly affected by outliers
  • Linear Regression is strongly affected by imbalanced classes

Visual

Class Activity

Class Activity 7