Lesson 14 Flashcards
- Predicts values of one variable based on information of the values of one or more variables.
- Uses the relation between two or more quantitative variables to predict the values of one variables using the values of the other variables
Regression Analysis
In regression analysis, ____? relationships cannot be determined
Causal
- Straight line that describes how the values of a response variable (y) depends on the values of an explanatory variable (x)
- The line with the “best fit” i.e. the line that minimizes the differences between the line and all the data points
Regression Line
Relationship approximated with a straight line
Linear Relationship
Determine (Perfect) Linear Relationship
- A perfect Straight line
- All X values correspond to Y
- Technique that produces the least square line
- Produces the prediction line that minimizes the sum of the squares of the deviations of the observed values from the predicted Y.
- The sum of squared deviations (Or the sum of the squared errors) denoted by SSE.
Ordinary Least Squares (OLS) Method
Correlation vs Regression
Correlation: Two values being measured are treated interchangeably
Regression: There is a clear asymmetry in the relationship between variables
Method for evaluating the relationship between 2 continuous variable
Simple Linear Regression
- Method used to visualize whether a relationship between two interval/ratio variables is linear
- The values of IV are placed on the x-axis while the values of DV are placed on the y-axis
Scatterplot or Scatter Diagram
In Simple Linear Regression, (X) is regarded as the ___?
Predictor, Explanatory, or Independent Variable
In Simple Linear Regression, (Y) is regarded as the ___?
Response, Outcome, or Dependent Variable
In the prediction equation 𝑌(hat) = α + βX + ε, what is Y(hat)?
Predicted value of the dependent variable, Y
In the prediction equation 𝑌(hat) = α + βX + ε, what is X?
Value of the independent variable, X
In the prediction equation 𝑌(hat) = α + βX + ε, what is ε?
Residuals or prediction error, e
In the prediction equation 𝑌(hat) = α + βX + ε, what is α?
The point where the line crosses the y-axis (X=0), intercept