average line plot with shaded confidence interval in ggplot2

Question

I am making a line plot and would like to plot the average with confidence interval in shades next to it. I can plot the data just as line plot, but that doesn't work quite well because the data is scattered way to much.

Data looks like this:

     subsidy_to_port tick industry_cost_to_store
1                20    7                1900000
2                20    8                2800000
3                20    9                3700000
4                20   10                4600000
5                20   11                5500000
6                20   12                6400000
7                20   13                7300000
8                20   14               10300000
9                20   15               13300000
10               20   16               16300000

The subsidy to port goes from 0 to 100 % in steps of 20, I want that factored to show 5 different graphs in one figure. The ticks go from 0 to 32, and the industry_cost_to_store gradually goes up. I tried this for the normal plot:

StoredCO215mln <- ggplot(i3, aes(x = tick, y =           
total_co2_emissions_captured)) + geom_point(aes(color =    
factor(subsidy_to_port))) + ylab("Amount CO2 captured") + labs(title   
= "Total CO2 captured in 32 years (subsidy = 15mln)") + 
scale_color_discrete(name="Subsidy to port (%)")

Choosing points gives a lot of scattered points, geom_line just does not work for this data. As you can see, the data set is called i3. I looked at the geom_ribbon command but cannot figure out how this works. All help appreciated! Thanks a lot.

Max

Konrad Rudolph Konrad Rudolph · Accepted Answer · 2019-01-31T10:48:19

From your description, the following should be what you want:

StoredCO215mln <- ggplot(i3) +
    aes(x = tick, y = total_co2_emissions_captured, color = factor(subsidy_to_port)) +
    geom_smooth(method = loess) +
    labs(title = "Total CO2 captured in 32 years (subsidy = 15mln)", y = "Amount CO2 captured") + 
    scale_color_discrete(name = "Subsidy to port (%)")

Since you mentioned “average line” I’ve used LOESS regression but you might want to play around with this and try others, e.g. simple linear regression.

average line plot with shaded confidence interval in ggplot2

2 Answers