# Regression Options

## Content



The RegressionOption object allows specification of the regression model. The [NumTerms](/componentone/api/win/online-chart2d/dotnet-framework-api/C1.Win.C1Chart.4.8/C1.Win.C1Chart.RegressionOptions.NumTerms.html) property defines the number of coefficients to be used by a regression, and is relevant only for regressions with variable number of terms (polynomial and Fourier).

For a polynomial regression, the number of terms is one more than the order of the resulting polynomial. The maximum number of terms for a polynomial is the number of data points, and the minimum number of terms is two (linear).

The following image illustrates a Linear Regression since its number of terms is two:

![](https://cdn.mescius.io/document-site-files/images/70bd33a2-280e-4cc3-a1c0-7b827eceb8aa/imagesext/image9_154.png)

The following image illustrates a Polynomial regression since its number of terms is more than two.

![](https://cdn.mescius.io/document-site-files/images/70bd33a2-280e-4cc3-a1c0-7b827eceb8aa/imagesext/image9_155.png)

[UseYIntercept](/componentone/api/win/online-chart2d/dotnet-framework-api/C1.Win.C1Chart.4.8/C1.Win.C1Chart.RegressionOptions.UseYIntercept.html) property controls whether the first term of polynomial regression is fixed, when UseYIntercept is **True** the trend line intercepts the line x=0 at y-coordinate that is defined by [Yintercept](/componentone/api/win/online-chart2d/dotnet-framework-api/C1.Win.C1Chart.4.8/C1.Win.C1Chart.RegressionOptions.YIntercept.html) property.

The following image illustrates a non-fixed Linear Regression since the UseYIntercept property is False.

![](https://cdn.mescius.io/document-site-files/images/70bd33a2-280e-4cc3-a1c0-7b827eceb8aa/imagesext/image9_156.png)

The following image illustrates a fixed Linear Regression since the trendline is set to intercept the line x=0 at y-coordinate that is defined by the **RegressionOptions.Yintercept** property:

![](https://cdn.mescius.io/document-site-files/images/70bd33a2-280e-4cc3-a1c0-7b827eceb8aa/imagesext/image9_157.png)

## See Also

[Regression Statistics](/componentone/docs/win/online-chart2d/chartingdata/workingwithtrendline/regressiontrendlines/regressionstatistics)