The Least-squares Trend Inference calculator computes the value of the dependent variable (Y) based on the intercept (a), the slope (b) and a value of X. This is the result of a least-squares trend linear equation, through a set of X and Y values. This is also known as simple linear regression.
INSTRUCTIONS: Enter the following:
Domain (Y): The calculator returns the value of Y.
Theis in the following form:
`b = ( (sum(XY) - (sumX * sumY)"/n")) / (sum(X^2) - (sumX)^2"/n") `
` a = MY - b*MX` MY is mean of Y. MX is mean of X.
After you have entered the values in the calculator for a, b and x, the plot function will let you enter a range (min and max) for x and a number of steps. When you enter the range for x and number of steps, it will generate a graph of the line graphing the values of y using your entered a and b, stepping through values of x between the range specified.