My data & code
library(ggplot2)
Year <- c(rep(1997, 8), rep(2004, 6), rep(2005, 3), rep(2006, 5),
rep(2007, 7), rep(2008, 2), rep(2009, 8), rep(2010, 12),
rep(2011, 18), rep(2012, 7), rep(2013, 6), rep(2014, 9),
rep(2015, 7), rep(2016, 5), rep(2017, 3), rep(2018, 18),
rep(2019, 40))
Group <- c(rep("b", 6), rep("c", 2), rep("b", 2), rep("c", 1), rep("d", 3),
rep("d", 3), rep("d", 5), rep("c", 1), rep("d", 6), rep("b", 2),
rep("a", 3), rep("b", 2), rep("c", 1), rep("d", 2), rep("b", 8),
rep("c", 4), rep("b", 1), rep("c", 6), rep("d", 11),rep("a", 1),
rep("b", 4), rep("c", 2), rep("a", 1), rep("c", 1), rep("d", 4),
rep("b", 5), rep("c", 4), rep("b", 2), rep("c", 5), rep("b", 1),
rep("c", 3), rep("d", 1), rep("a", 2), rep("d", 1), rep("a", 3),
rep("b", 7), rep("c", 7), rep("d", 1), rep("a", 13), rep("d", 27))
data <- data.frame(Year, Group)
table(data$Year, data$Group)
Doing tables on this would suggest that there's a huge bump in group D in 2019. By the end, Group D has 39% of observations and A has 14% (2018 it was 29% and 8%).
table(data$Year, data$Group)
a b c d
1997 0 6 2 0
2004 0 2 1 3
2005 0 0 0 3
2006 0 0 0 5
2007 0 0 1 6
2008 0 2 0 0
2009 3 2 1 2
2010 0 8 4 0
2011 0 1 6 11
2012 1 4 2 0
2013 1 0 1 4
2014 0 5 4 0
2015 0 2 5 0
2016 0 1 3 1
2017 2 0 0 1
2018 3 7 7 1
2019 13 0 0 27
But, when I do geom_density in ggplot2:
ggplot(data, aes(x=Year)) +
stat_density(geom="line", aes(group=Group, linetype=Group, color=Group))+
ylab("Density")+
scale_colour_manual(values = c("brown","gold", "green", "red"))+
scale_linetype_manual(values = c("twodash", "solid", "dotted", "longdash")) +
theme_bw()+
theme(panel.grid.major=element_blank(),
panel.grid.minor=element_blank(),
panel.border=element_blank(),
axis.line=element_line(),
text=element_text(family='Times'),
legend.title=element_blank())
Group A has this huge bump. I've checked the levels; I've tried it with lattice::densityplot(), etc. Am I not understanding how geom_density displays things?
Edit: Adding a photo of the graph that gets outputted for clarity.
