Influence Analysis

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LEVEL II In regression analysis, influence analysis is a method used to identify which observations in a dataset have a disproportionate effect on the estimated regression coefficients. This can help to identify outliers or observations that are having a large effect on the overall regression model. There are several measures that can be used to determine the influence of an …

Multicollinearity

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Multicollinearity occurs when two or more independent variables in a multiple regression model are highly correlated with each other. This can create problems when interpreting the regression coefficients, as the estimated coefficients of the correlated variables can change erratically in response to small changes in the data or the model. There are several ways to detect multicollinearity in a regression …

Breusch-Godfrey test [BG Test]

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LEVEL II The Breusch-Godfrey test is a statistical test that is used to detect autocorrelation in the residuals of a linear regression model. It helps to detect autocorrelation at different lags and it’s applicable to both linear and non-linear models. The test starts with an initial regression where we record down all the residuals for each time period. The residual …

Serial Correlation

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LEVEL II Autocorrelation is the correlation of a time series with a lagged version of itself. It measures the similarity between a given time series and a lagged version of the same time series. Positive autocorrelation means that the time series is positively correlated with a lagged version of itself, while negative autocorrelation means that the time series is negatively …

Joint hypothesis test

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LEVEL II A joint hypothesis test is an F-test to evaluate nested models, which consist of a full or unrestricted model, and a restricted model. The F-statistic is calculated using the formula shown. The null hypothesis would be that all coefficients of the excluded variables are equal to zero, and the null that at least one of the excluded coefficients …