Chapter 4 (4-4.4.1) Flashcards
What are predictors?
Variables that you use to make predictions.
What are outcome variables?
Variables you want to predict.
True or false: predictors are “Y” and outcome variables are “X”.
False
True or false: predictors are independent variables and outcome variables are dependent variables.
True
What does the correlation coefficient range from?
-1 to 1.
How do you make good predictions?
By choosing predictors that are highly correlated with outcome variables, i.e. predictors that have a strong linear association with outcome variables.
What’s another word for prediction errors?
“residuals”.
How is the relationship between X and Y summarized?
With a line.
What does the intercept of a line specify?
The vertical location of the line.
What does the slope of a line specify?
The steepness of the line.
True or false: on a scatter plot, predictors are always on the y-axis and outcome variables are always on the x-axis.
What’s the aim of estimating causal effects?
To estimate the effect of X on Y.
What’s the aim of inferring population characteristics?
To infer the characteristics of X on the population.
What’s the aim of making predictions?
To predict Y as accurately as possible.
Account for the “least squares” method.
A mathematical approach used to find the best-fitting line or curve for a dataset by minimizing the sum of the squares of the difference (residuals) between observed values and predicted values.
A line is defined by two coefficients; what are they?
- intercept (specifies the vertical location of the line)
- slope (specifies the steepness of the line)
True or false: the line that best summarizes the relationship between X and Y can be used to make predictions.
True
