Airline-competitiveness: Evidence from the U.S. Domestic Market

Contents

DataProcessing

2. …

PanelDataModeling

0. Import Libraries and Load Data
1. Data Preparation for PanelData Model

I. Bassic Panel Model

1. PooledOLS model
2. RandomEffects model
3. BetweenOLS model

II. Testing correlated effects

1. Testing for Fixed Effects
2. Testing for Time Effects
3. First Differences

III. Comparison

1. Comparing between modelBetween, modelRE and modelPooled models
2. Comparing between Robust, Entity and Entity-Time mothods

IV. Instruments as lags of order 1 and 2 of first differences

• Campute the lags of order 1 and 2 of first differences

V. Linear Instrumental-Variables Regression

1. 2SLS as OLS
2. IV 2SLS 1. Sargan test: Testing the absence of correlation between Z and U 2. Testing the correlation of Z and X_endog 3. Endogeneity testing using Durbin and Wu-Hausman test of exogeneity 4. Augmented test for testing the exogeneity of log_fare 5. Instrumenting using two-stage least squares 6. Homoskedasticity – Heteroskedasticity
   1. Breusch–Pagan test
   2. White test 7. Testing Autocorrelation

VI. GMM Estimation

1. Exogeneity test using Sargan-Hansen test
2. Exogeneity test using the augmented regression approach

VII. Feasible Generalized Least Squares (GLS) and GLSA model