Corrected typo in Unusual values (hadley#512)

the unusually wide limits are either on the y-variable or on the x-axis

EDA.Rmd

@@ -164,7 +164,7 @@ Many of the questions above will prompt you to explore a relationship *between*
 
 ### Unusual values
 
-Outliers are observations that are unusual; data points that don't seem to fit the pattern. Sometimes outliers are data entry errors; other times outliers suggest important new science. When you have a lot of data, outliers are sometimes difficult to see in a histogram.  For example, take the distribution of the `y` variable from the diamonds dataset. The only evidence of outliers is the unusually wide limits on the y-axis.
+Outliers are observations that are unusual; data points that don't seem to fit the pattern. Sometimes outliers are data entry errors; other times outliers suggest important new science. When you have a lot of data, outliers are sometimes difficult to see in a histogram.  For example, take the distribution of the `y` variable from the diamonds dataset. The only evidence of outliers is the unusually wide limits on the x-axis.
 
 ```{r}
 ggplot(diamonds) +