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Real Data Analysis. Linear VS Non-Linear. Regression http://n-steps.tetratech-ffx.com/PDF%26otherFiles/stat_anal_tools/regression_final.pdf. One of the most common statistical modeling tools used, regression is a technique that treats one variable as a function of another.
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Real Data Analysis Linear VS Non-Linear
Regression http://n-steps.tetratech-ffx.com/PDF%26otherFiles/stat_anal_tools/regression_final.pdf • One of the most commonstatistical modeling tools used, regression is a technique that treats one variable as a function of another. • The result of a regression analysis is an equation that can be used to predict a response from the value of a given predictor. • Regression is often used in experimental tests where … one tests whether there is a significant increase or decrease in the response variable ….
What’s that mean? • One tool used in the ‘real world’ to help make business decisions and determine the results of scientific experiments is regression analysis. • You use regression analysis to see if one thing (like the periods of time a store is open) strongly affects another thing (like how much money the store makes). • There are many types of regression analysis. • Two of those are linear and nonlinear.
Linear Regression line of best fit scatterplot • The relationship between the two variables is directly proportional. • Directly Proportional: If one value increases, the other increases as well. • The function that passes through the middle of the scatterplot is called the line of best fit. Linear Regression Model
Nonlinear Regressions • There are many types of nonlinear regressions due to the fact that they are anything that is not linear. • Quadratic Regression • Cubic Regression • Quartic Regression • Power Regression • Exponential Regression • Logarithmic Regression • Logistic Regression
Nonlinear Regressions • Quadratic Regression • Cubic Regression Y=ax2+bx+c Y=ax3+bx2+cx+d
Nonlinear Regressions • Quartic Regression • Power Regression Y=ax4+bx3+cx2+dx+c Y=axb
Nonlinear Regressions • Exponential Regression • Logarithmic Regression Y=kax Y=klogax
Nonlinear Regressions • Logistic Regression
Calculating a Regression Function Step One: Press STAT Step Two: Select EDIT Step Three: Enter the data
Calculating a Regression Function Step Four: Press STAT PLOT Step Five: Select 1 Step Six: Select ON
Calculating a Regression Function Step Seven: Press WINDOW Step Eight: Adjust x-min, x-max, y-min, and y-max Step Nine: Press GRAPH
Calculating a Regression Function Step Ten: Press STAT Step Eleven: Select CALC Step Twelve: Select 4: LinReg(ax+b) [we’re going to see if it’s linear] Step Thirteen: Tell the Calculator where you want the equation stored.
(How to find the Y-Variables) Press VARS
Calculating a Regression Function Step Fourteen: Press ENTER Step Fifteen: Press GRAPH Does that look like the graph is best fit with a line?
Calculating a Regression Function The best regression equation for this set of data is