Linear Regression Flashcard

Front

What is linear regression?

Back

Linear regression is a statistical method used to model the relationship between a dependent variable and one or more independent variables by fitting a linear equation to observed data.

Front

What does the correlation coefficient (r) indicate?

Back

The correlation coefficient (r) measures the strength and direction of a linear relationship between two variables, ranging from -1 (perfect negative correlation) to +1 (perfect positive correlation).

Front

What does a weak negative correlation mean?

Back

A weak negative correlation indicates that as one variable increases, the other variable tends to decrease slightly, but the relationship is not strong.

Front

What is the equation of the line of best fit?

Back

The equation of the line of best fit is a linear equation that best represents the data points in a scatter plot, typically expressed in the form y = mx + b, where m is the slope and b is the y-intercept.

Front

How do you calculate the slope (m) in linear regression?

Back

The slope (m) in linear regression is calculated using the formula: m = (NΣ(xy) - ΣxΣy) / (NΣ(x^2) - (Σx)^2), where N is the number of data points.

Front

What is the significance of the y-intercept (b) in a linear equation?

Back

The y-intercept (b) is the value of the dependent variable when the independent variable is zero, representing the starting point of the line on the y-axis.

Front

What does it mean if r = 0?

Back

If r = 0, it indicates that there is no linear correlation between the two variables, meaning changes in one variable do not predict changes in the other.

Front

What is a scatter plot?

Back

A scatter plot is a graphical representation of two variables, showing the relationship between them by displaying data points on a Cartesian plane.

Front

What does a strong positive correlation indicate?

Back

A strong positive correlation indicates that as one variable increases, the other variable also increases, and the relationship is close to a straight line.

Front

What is the purpose of linear regression analysis?

Back

The purpose of linear regression analysis is to predict the value of a dependent variable based on the value(s) of one or more independent variables.