Deriving Ordinary Least Squares Estimates

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What is the total sum of squares (SST) in OLS regression?

The explained sum of squares (SSE)

The sum of squared residuals (correct)

The variation explained by x

The residual sum of squares (SSR)

If the OLS intercept and slope estimates are multiplied by a constant c, what happens?

They increase proportionally (correct)

They remain unchanged

They become undefined

They decrease proportionally

What does the residual sum of squares (SSR) represent in OLS regression?

The unexplained variation in the dependent variable (correct)

The fraction of sample variation explained by x

The explained variation compared to the total variation

The total variation in the dependent variable

If the independent variable in OLS regression is divided by a constant c, what happens to the OLS slope coefficient?

It decreases proportionally Signup and view all the answers

What is the interpretation of R-squared in regression analysis?

The fraction of sample variation in y explained by x Signup and view all the answers

Incorporating nonlinearities, what form is used in the example of a Log Wage Equation?

Semi-logarithmic form Signup and view all the answers

What is the purpose of the error term in a regression model?

To represent the variability in the dependent variable that is not explained by the independent variable Signup and view all the answers

In a regression analysis, what does a residual represent?

The difference between the actual observed value and the predicted value by the regression model Signup and view all the answers

How are Ordinary Least Squares estimates calculated in a regression model?

By minimizing the sum of squared residuals Signup and view all the answers

What does it mean if a residual is negative?

The observed value is less than the predicted value by the regression model Signup and view all the answers

Why is minimizing the sum of squared residuals important in regression analysis?

It ensures that the model fits the data as closely as possible Signup and view all the answers

What effect does an outlier have on the sum of squared residuals in a regression model?

Increases the sum of squared residuals Signup and view all the answers

What does the sum of squared residuals represent in the context of Ordinary Least Squares (OLS)?

The total sum of the unexplained errors Signup and view all the answers

What is the significance of having a sample covariance of zero between regressors and OLS residuals?

It implies no linear relationship between the independent and dependent variables Signup and view all the answers

What is the primary interest in most cases when determining Ordinary Least Squares (OLS) regression estimates?

The slope of the regression line Signup and view all the answers

What does it signify if the OLS regression line underpredicts yi for a given observation?

The residual for that observation is positive Signup and view all the answers

What does Property 3 of Algebraic Properties of OLS Statistics state?

The OLS regression line passes through a specific point Signup and view all the answers

In terms of OLS, what does it mean if the sample average of the OLS residuals is zero?

The errors in prediction balance out to zero on average Signup and view all the answers