Hi All,

I am looking to create an interaction plot where I need to get the mean of linear growth. Using the summarize function, my mean is different from the mean i manually calcuated from excel.

Here is my a subset of my data.

The mean for the linear growth for yellow at time 2 is 118.7050667.

Using the summarize function on R :

sum = Summarize(Linear.Extension.mm.~ Time_factor+ Colour)

sum$se= sum$sd / sqrt(sum$n)

sum

Time_factor Colour n mean sd min Q1 median Q3 max se

1 Time_0 Blue 15 78.60000 26.23193 22 65.50 83.0 91.00 123 6.773056

2 Time_1 Blue 15 84.53333 46.72697 13 48.00 94.0 118.00 147 12.064851

3 Time_2 Blue 15 45.26667 50.18461 2 11.50 31.0 40.50 148 12.957611

4 Time_0 Brown 20 76.95000 25.22629 46 55.00 74.5 102.00 120 5.640770

5 Time_1 Brown 20 86.40000 42.91411 3 65.25 99.5 117.50 138 9.595887

6 Time_2 Brown 20 83.70000 51.79524 10 34.50 88.0 131.75 150 11.581769

7 Time_0 Yellow 15 76.86667 24.27187 45 62.50 69.0 85.50 132 6.266971

8 Time_1 Yellow 15 93.73333 45.38324 1 66.00 110.0 126.50 142 11.717901

9 Time_2 Yellow 15 46.60000 49.46543 4 16.00 27.0 42.50 145 12.771919

this is what i got. all the mean from different colors at different time are different from those manually calculate from excel.

Does anyone know why this happened? or is there a better function?

*UPDATE*

All the codes type from the console.

library(ggplot2)

library(rlang)

attach(data1)

library(FSA)

sum = Summarize(lineargrown ~ color+Time,)

sum$se= sum$sd / sqrt(sum$n)

sum

pd = position_dodge(.2)

ggplot(sum,

aes(x = Time,

y = mean,

color = color)) +

geom_point(shape = 15,

size = 4,

position = pd) +

geom_errorbar(aes(ymin = mean - se,

ymax = mean + se),

width = 0.2,

size = 0.7,

position = pd) +

theme_bw() +

theme(axis.title = element_text(face = "bold")) +

ylab("Linear Growth")