Code for making "Active Window" trends plot on http://john-joseph-horton.com/

code_for_making_freelancer_active_window_trends_plot.R

library(JJHmisc)
library(oDeskTools) #internal package for working with oDesk data
library(ggplot2)
library(reshape2)
library(scales)

connectDB(get_credentials())

df.wide <- dbGetQuery(con, "select * from active_window_trends")

df <- melt(df.wide, id.vars = c("year"))
df.compare <- merge(subset(df, year == 2010), 
                    subset(df, year == 2013), by = "variable")
df.compare$pct <- with(df.compare, round(100 * (value.y - value.x)/value.x))
df.compare$pct.label <- with(df.compare, sprintf('%.1f', pct))
df.final <- merge(df, df.compare[, c("variable", "pct.label", "pct")])
df.final$better.label <- with(df.final, paste0(variable,": ", pct.label, "%"))
df.final$direction <- with(df.final, sign(pct))

g <- ggplot(data = df.final, aes(x = year, y = value)) +
    geom_line(aes(group = variable)) +
    geom_text(data = subset(df.final, year == 2013),
              aes(x = year,
                  y = value,
                  hjust = 0, 
                  colour = factor(direction), 
                  label = better.label)) +
    geom_text(data = subset(df.final, year == 2010),
              aes(x = year,
                  y = value,
                  hjust = 1, 
                  colour = factor(direction), 
                  label = variable)) +  
    theme_bw() +
    scale_y_log10(labels = percent) + 
    scale_colour_manual(values=c("red", "darkgreen")) +
    xlab("Year") +
    ylab("Percentage of Observations for Month of August (Log Scale)") +
    theme(legend.position = "none") +
    labs(title = "Changes in Freelancer 'Active Window'")


writeImage(g, "what_freelancers_use", width = 9, height = 12, path = "./")