Forum Discussion

Anonymous's avatar
Anonymous
Not applicable
6 years ago
Solved

R Script - Overlay Normal Distribution Curve

Hi everyone, 

 

Having a bit of an issue overlaying a normal distribution curve on a histogram visual, using R scripts. 

 

# The following code to create a dataframe and remove duplicated rows is always executed and acts as a preamble for your script: 

# dataset <- data.frame(Ratings)
# dataset <- unique(dataset)

# Paste or type your script code here:
library(ggplot2)
ggplot(data=dataset,aes(x=dataset$Ratings)) +
    geom_histogram(aes(y=..density..),col="#ffffff",fill="#bfd730") +
    labs(title="Employee 2019 Performance Rating", x="Performance Ratings", y="Frequency") +
    geom_density(col=2) 

#Adding Normal Curve 
ratings_norm_curve=rnorm(length(Ratings),mean(Ratings),sd(Ratings))

#Adding it to Histogram 
lines(density(ratings_norm_curve, adjust = 2), col="blue", lwd=2)

What might I be doing wrong here?  

Need Help
Tips and Tricks
  • Icey's avatar
    Icey
    6 years ago

    Hi Anonymous ,

     

    Sorry to reply late. Please check whether this could meet your requirements:

    library(ggplot2)
ggplot(data=dataset,aes(x=dataset$Ratings)) +
    geom_histogram(aes(y=..density..),col="#ffffff",fill="#bfd730") +
    labs(title="Employee 2019 Performance Rating", x="Performance Ratings", y="Frequency") +
    geom_density(col=2) +
    stat_function(fun = dnorm, 
        args = list(mean = mean(dataset$Ratings, na.rm = TRUE), 
                    sd = sd(dataset$Ratings, na.rm = TRUE)), 
                    colour = 'blue')

     

     

    Best Regards,

    Icey

     

    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

6 Replies

  • Icey's avatar
    Icey
    Community Support
    6 years ago

    Hi Anonymous ,

     

    Please share me some dummy sample data, not real data, for test.

     

     

    Best Regards,

    Icey

     

    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

    • Anonymous's avatar
      Anonymous
      Not applicable
      6 years ago

      Icey  apologies for the delay, but you I curated the dataset for you - it's a sample, and within the spreadsheet I've included the current visual output, the code I'm using, and a desired outcome statement. 🙂 

       

      Let me know what you've come up with! Appreciate your assistance with this. 

      Thanks Much! 

  • Icey's avatar
    Icey
    Community Support
    6 years ago

    Hi Anonymous ,

     

    Sorry to reply late. Please check whether this could meet your requirements:

    library(ggplot2)
ggplot(data=dataset,aes(x=dataset$Ratings)) +
    geom_histogram(aes(y=..density..),col="#ffffff",fill="#bfd730") +
    labs(title="Employee 2019 Performance Rating", x="Performance Ratings", y="Frequency") +
    geom_density(col=2) +
    stat_function(fun = dnorm, 
        args = list(mean = mean(dataset$Ratings, na.rm = TRUE), 
                    sd = sd(dataset$Ratings, na.rm = TRUE)), 
                    colour = 'blue')

     

     

    Best Regards,

    Icey

     

    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

    • Anonymous's avatar
      Anonymous
      Not applicable
      6 years ago

      Yes thank you so much!!! 🙂 

       

    • Anonymous's avatar
      Anonymous
      Not applicable
      6 years ago

      Icey  is it possible to show the count of frequency on the x-axis of this code?