#################
### Data load ###
#################
# https://data.giss.nasa.gov/gistemp/graphs/
# https://en.wikipedia.org/wiki/List_of_Presidents_of_the_United_States
# Drop Hayes and Garfield (1880-1881) since the temperature record starts in the middle
# of Hayes' term and no trend can be calculated for Garfield (< 1 year in office)
dat = read.csv("globalTemp.csv", stringsAsFactors = F)
dat = dat[-(1:2), ]


############
### Prep ###
############
pres = unique(unlist(strsplit(dat$President, "/")))
res  = data.frame(pres  = pres,
                  party = NA,
                  t0    = NA,
                  tF    = NA,
                  yrs   = NA,
                  slope = NA,
                  stringsAsFactors = F)

for(i in 1:length(pres)){
  idx          = grep(pres[i], dat$President)
  res$party[i] = dat$Party[which(dat$President == pres[i])[1]]
  res$t0[i]    = head(dat$Year[idx], 1)
  res$tF[i]    = tail(dat$Year[idx], 1)
  res$yrs[i]   = res$tF[i] - res$t0[i]
  res$slope[i] = coef(lm(Temp~Year, dat[idx,]))[2]
  res$total[i] = res$yrs[i]*res$slope[i]
}