# Violin Plot¶

Visualize the distribution of feature values in a violin plot.

**Inputs**

- Data: input dataset

**Outputs**

- Selected Data: instances selected from the plot
- Data: data with an additional column showing whether a point is selected

The **Violin Plot** widget plays a similar role as a Box Plot. It shows the distribution of quantitative data across several levels of a categorical variable such that those distributions can be compared. Unlike the Box Plot, in which all of the plot components correspond to actual data points, the Violin Plot features a kernel density estimation of the underlying distribution.

Select the variable you want to plot. Tick

*Order by relevance to subgroups*to order variables by Chi2 or ANOVA over the selected subgroup.Choose

*Subgroups*to see violin plots displayed by a discrete subgroup. Tick*Order by relevance to variable*to order subgroups by Chi2 or ANOVA over the selected variable.*Box plot*: Tick to show the underlying box plot.*Strip plot*: Tick to show the underlying data represented by points.*Rug plot*: Tick to show the underlying data represented by lines.*Order subgroups*: Tick to order violins by*median*(ascending).*Orientation*: Determine violin orientation.*Kernel*: Select the kernel used to estimate the density. Possible kernels are:*Normal*,*Epanechnikov*and*Linear*.*Scale*: Select the method used to scale the width of each violin. If*area*is selected, each violin will have the same area. If*count*is selected, the width of the violins will be scaled by the number of observations in that bin. If*width*is selected, each violin will have the same width.

## Examples¶

The **Violin Plot** widget is most commonly used immediately after the File widget to observe the statistical properties of a dataset. In the first example, we have used *heart-disease* data to inspect our variables.

The **Violin Plot** could also be used for *outlier detection*. In the next example we eliminate the outliers by selecting only instances that fall inside the Q1 − 1.5 and Q3 + 1.5 IQR.