Standard error of y estimate (also known as Standard Error of a regression) shows how big the prediction error is After changing the variables to X = ln ( x), the calculations become similar to the linear case Y = b * x + A:Įxcel offers the following functions to calculate trendline parameters: Note: Excel the logarithmic function approximation into the linear model fitting: the logarithmic function y = a * ln ( x) + b is transformed into a linear function using a change of variables. The LN () function returns the natural logarithm of a given number: The logarithmic trendline is a curved line with the function:
Logarithmic trendline equation and formulas a dependent or response variable y (named as known_y's).an independent, predictor, or explanatory variable x (named as known_x's),.Excel uses the least squares method to fit a trend line to the data points.įor a trend line, two sets of variables are required:
