Slope: used to measure the inclination of a slope. Mathematically, the slopes of straight lines are equal everywhere, which is a measure of the inclination of straight lines. Through algebra and geometry, the slope of a straight line can be calculated; The tangent slope of a point on the curve reflects the changing speed of the variable of this curve at this point. The tangent slope of any point on the curve can be calculated by calculus. The concept of the slope of a straight line is equivalent to the slope in civil engineering and geography.

Formula: ax+by+c=0, where k =-a/b.

Intercept: Mathematically, it refers to the (horizontal or vertical) coordinates of all intersections between a function and a coordinate axis, which can be any number.

Formula: for a linear function y=kx+b, b is the intercept of the function image.

Mathematically, we can find two points (x 1, y 1)(x2, y2), and then the slope k = (y1-y2)/(x1-x2);

Intercept can bring x=0 into the function, and the value of y is the intercept.

Correlation coefficient: it is a statistical index to reflect the close correlation between variables. The correlation coefficient is calculated according to the product-difference method, which is also based on the deviation between two variables and their respective average values, and the correlation degree between the two variables is reflected by multiplying the two deviations; The linear single correlation coefficient is studied emphatically.