Topic models

We will leave behind the 19th century and look at these recent times of trial and tribulation (1965 through 2016). In looking at this data, I found something interesting and troubling. Let's take a look at the 1970s:

> sotu_meta[185:191, 1:4]
# A tibble: 7 x 4
  president        year  years_active party 
  <chr>            <int> <chr>        <chr> 
1 Richard M. Nixon 1970  1969-1973    Republican
2 Richard M. Nixon 1971  1969-1973    Republican
3 Richard M. Nixon 1972  1969-1973    Republican
4 Richard M. Nixon 1972  1969-1973    Republican
5 Richard M. Nixon 1974  1973-1974    Republican
6 Richard M. Nixon 1974  1973-1974    Republican
7 Gerald R.   Ford 1975  1974-1977    Republican

We see there are two 1972 and two 1974 addresses, but none for 1973. What? I went to the Nixon Foundation website, spent about 10 minutes trying to deconflict...