# Selection of a trend line. Trendline & R²

The type of data you have determines the type of trendline you should use.

Polynomial Power These options tell Tableau to build a linear regression model based on this type of transformation on one or both variables. How can I add a trend line? You can add a trend line in a couple of different ways.

By default, this gives a linear model trend line. You can also use the Drag and Drop options selection of a trend line the Analytics pane.

If you click on this and drag across, you will be given the different options available for your type of graph. Now, simply drag your mouse to the type of trend line that you want to add.

Removing a trend line is just as simple, just click and drag it off the view. And edit a trend line? This will bring up a dialogue box with a variety of different options for our trend line depending on graph and model type.

### Day Trading Rules - Secret to Using Fibonacci Levels

Assessing whether a trend line provides us with useful information is really important. The P-value and R-squared are vital when it comes to assessing whether the trend line model is useful or not and which model is best suited to your data.

P-value The p-value is a measure of significance for the trend line. A p-value of 0.

A large p-value can indicate that the apparent trend in the data is due to chance, not the factors in the model. R-squared The R-squared is also an important measure when assessing if the model is suitable and tells us whether the model effectively fits our data. The R-squared is measured on a scale from ; the closer to 1 the more effective the model.