Here are 3 ways to create a jitter plot in R, also called a strip chart or a dot plot which is a one-dimensional scatter plot. A jitter plot in R makes it easier to view overlapping data points by categorical or discrete values.

In that scenario, the scatter plot groups all data points in one line above the category, but the jitter plot creates additional dispersion. In other words, this variation of scatter plot displays numerical data along a single strip and jitter to avoid substantial overlap.

## Jitter plot in R using *ggplot2*

Here is a scatter plot that you can make with the *geom_point*.

require(ggplot2) ggplot(chickwts, aes(x = feed, y = weight)) + geom_point( size = 3, alpha = 0.7, shape = 16, color = "cadetblue") + geom_vline( xintercept = seq(1.5, length(unique(chickwts$feed)), by = 1), color = "gray90", size = 1) + labs( title = "the effectiveness of various feed supplements", subtitle = "on the growth rate of chickens after six weeks", x = "feed type", y = "weight (grams)") + theme_minimal() + theme(panel.grid = element_blank())

There are no default gridlines, and here is more about them. In this case, there are vertical lines between *ggplot2* axis categories. All data points are above the category, and they overlap. It might be hard to evaluate data in general.

By using the *geom_jitter*, you can create a jitter plot in *ggplot2*, and the difference in the result is noticeable.

set.seed(123) ggplot(chickwts, aes(x = feed, y = weight)) + geom_jitter( size = 3, alpha = 0.7, shape = 16, width = 0.2, color = "cadetblue") + geom_vline( xintercept = seq(1.5, length(unique(chickwts$feed)), by = 1), color = "gray90", size = 1) + labs( title = "the effectiveness of various feed supplements", subtitle = "on the growth rate of chickens after six weeks", x = "feed type", y = "weight (grams)") + theme_minimal() + theme(panel.grid = element_blank())

### Horizontal jitter with *ggplot2*

If you want to rotate the *ggplot2* plot, you can do that like in this post by using the *coord_flip*.

set.seed(123) ggplot(chickwts, aes(x = feed, y = weight)) + geom_jitter( size = 3, alpha = 0.7, shape = 16, width = 0.2, color = "cadetblue") + geom_vline( xintercept = seq(1.5, length(unique(chickwts$feed)), by = 1), color = "gray90", size = 1) + labs( title = "the effectiveness of various feed supplements", subtitle = "on the growth rate of chickens after six weeks", x = "feed type", y = "weight (grams)") + coord_flip()+ theme_minimal() + theme(panel.grid = element_blank())

## Jitter plot in *plotly*

You might be interested to get an interactive jitter plot. If you have the jitter plot in *ggplot2*, the easiest way is to translate that into *plotly*. Here is how to do that, but there is a problem with the subtitle.

require(plotly) set.seed(123) ggplotly( ggplot(chickwts, aes(x = feed, y = weight)) + geom_jitter( size = 3, alpha = 0.7, shape = 16, width = 0.2, color = "cadetblue") + geom_vline( xintercept = seq(1.5, length(unique(chickwts$feed)), by = 1), color = "gray90", size = 1) + labs( title = "the effectiveness of various feed supplements", subtitle = "on the growth rate of chickens after six weeks", x = "feed type", y = "weight (grams)") + theme_minimal() + theme(panel.grid = element_blank()) )

As I mentioned, there is a problem with the R *plotly* subtitles after using the *ggplotly* function. Here is a post with the solution to fix that.

require(dplyr) ggplotly( ggplot(chickwts, aes(x = feed, y = weight)) + geom_jitter( size = 3, alpha = 0.7, shape = 16, width = 0.2, color = "cadetblue") + geom_vline( xintercept = seq(1.5, length(unique(chickwts$feed)), by = 1), color = "gray90", size = 1) + labs( title = "the effectiveness of various feed supplements", subtitle = "on the growth rate of chickens after six weeks", x = "feed type", y = "weight (grams)") + theme_minimal() + theme(panel.grid = element_blank()) ) %>% layout(title = list(text = paste0('the effectiveness of various feed supplements', '<br>', '<sup>', 'on the growth rate of chickens after six weeks', '</sup>')))

## Jitter plot in base R

It is worth respecting the functionality of base R. Despite the improvements of multiple packages, some of the base functionality is better. Here is a jitter plot in base R that looks pretty enough. The tricky part is to add a subtitle in the base R plot.

set.seed(123) stripchart( chickwts$weight ~ chickwts$feed, vertical = TRUE, pch = 20, cex = 1.5, col = "sky blue", method = "jitter", frame.plot = FALSE, ylab = "weight (grams)", xlab = "feed type", main = "the effectiveness of various feed supplements" ) subtitle <- "on the growth rate of chickens after six weeks" mtext(at = 1, adj = -0.8, subtitle)

## Jitter chart in Excel

Sometimes it is necessary to do something similar in Excel. It is not as easy as it is in R, but doable. Here are two posts that will help you.

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