• ECONOMETRICS I
  • 1 Preface
    • 1.1 Welcome
    • 1.2 Context
  • I Overview
  • 2 What is Econometrics
  • 3 This Course
    • 3.1 Virtual Campus
      • 3.1.1 Contents
      • 3.1.2 Calendar
      • 3.1.3 Grading
      • 3.1.4 Course Format
    • 3.2 Bibliography
      • 3.2.1 Basic bibliography
      • 3.2.2 Recommended bibliography
      • 3.2.3 Software
    • 3.3 Gretl
      • Ingredients
      • Recommendations
  • 4 Design of Experiments
  • 5 Causal Models
    • 5.1 An Example
    • 5.2 Regression Analysis
  • 6 Case 01: Monet
    • 6.1 Dataset
      • 6.1.1 What Are Variables?
    • 6.2 Descriptive Statistics
      • 6.2.1 Data Summary and Presentation
    • 6.3 Data Display
    • 6.4 The Output
      • 6.4.1 Distribution I
      • 6.4.2 Distribution II
    • 6.5 New variables
      • 6.5.1 Relation with PRICE
    • 6.6 Comparing Group Means
      • 6.6.1 Decision Making for Single Sample
      • 6.6.2 Decision Making for Two Samples
  • 7 Case 02: Mobile
    • 7.1 Data
    • 7.2 Describing Data
    • 7.3 Price by OS
      • 7.3.1 Data
      • 7.3.2 Research question
      • 7.3.3 Preparing Data
      • 7.3.4 Mean Comparison
      • 7.3.5 More on data visualization
    • 7.4 Price by Brand
    • 7.5 Price by Screen Size
    • 7.6 Price by Storage Capacity
    • 7.7 Price by Dual Sim
  • II Design of Experiments
  • 8 Introduction
    • 8.1 An Example
  • 9 Hypothesis Testing
    • 9.1 How to?
    • 9.2 Terminology
    • 9.3 A snapshot
  • 10 Inference on the Mean
    • 10.1 One-Sample: Hypothesis Testing on the Mean
      • 10.1.1 Example
    • 10.2 Two-Samples: Hypothesis Testing on the Difference in Means
      • 10.2.1 Independent samples and Equal variances
      • 10.2.2 Example
    • 10.3 p-values: t Distribution
  • III Causal Models
  • 11 What are causal models?
  • 12 Simple Linear Regression
    • 12.1 Straigh Line Relationship
    • 12.2 Topics to cover
      • 12.2.1 Our Monet Case
    • 12.3 Regression Basics
    • 12.4 Calculating the Regression Line
      • 12.4.1 Technical Note: the “Best Fitting Line”
    • 12.5 Hypothesis Testing on Parameters
    • 12.6 Confidence Intervals
      • 12.6.1 Confidence Interval on Regression Coefficients
      • 12.6.2 Confidence Interval on Fitted Values
    • 12.7 Coefficient of Determination
      • 12.7.1 Technical notes
    • 12.8 Dummy Variables
      • 12.8.1 A Dummy variable
      • 12.8.2 In the Model
      • 12.8.3 An Example
    • 12.9 Log-Log Models
    • 12.10 Quadratic Models
      • 12.10.1 Example
    • 12.11 Parameter Interpretation
    • 12.12 Spurious Regression
  • 13 Multiple Linear Regression
    • 13.1 Applications
    • 13.2 Model Parameters
    • 13.3 Fitted Values and Residuals
    • 13.4 ANOVA
    • 13.5 R-squared, and Adjusted R-squared
    • 13.6 Significance Testing of Each Variable
    • 13.7 Assumptions of Multiple Linear Regression
    • 13.8 Multicollinearity
      • 13.8.1 The problem
      • 13.8.2 Exact collinearity
      • 13.8.3 Indicators of Multicollinearity
      • 13.8.4 Detecting Multicollinearity
      • 13.8.5 Corrections for Multicollinearity
      • 13.8.6 Our Monet Case
      • 13.8.7 Revisiting Monet Case
    • 13.9 Heteroscedasticity
  • Appendix
  • A Descriptive Statistics
  • B In Excel
  • C Students’t Distribution
    • C.1 Degrees of Freedom (df)
    • C.2 Area under the curve
    • C.3 The t-table
    • C.4 Acceptance/Rejection Region
  • D Datasets
    • D.1 Case 1
    • D.2 Case 2
    • D.3 Case 3
    • D.4 Case 4
    • D.5 Case 5
    • D.6 Case 6
    • D.7 Case 7
    • D.8 Case 8
    • D.9 Case 9
  • E About me
  • Universidad Nebrija.
    Published with bookdown

Econometrics I | Class Notes

7.7 Price by Dual Sim


Sources

  • Predicting Mobile Phone Prices
  • Product Chart
  • Comparing Means of Two Groups in R