Hao-2_7

Setup.

library(VennDiagram)

2.7

Proportional contingency table:

##                 Swing Not Swing Total
## Independent        11        24    35
## Not Independent    12        53    65
## Total              23        77   100

1. Are being Independent and being a swing voter disjoint, i.e. mutually exclusive?

• No, some voters are Independent and swing voters.

2. Draw a Venn diagram summarizing the variables and their associated probabilities.

draw.pairwise.venn(area1 = 35, area2 = 23, cross.area = 11, 
                   category = c('% Independent', '% Swing Voter'), 
                   cat.pos = c(3, -1))

## (polygon[GRID.polygon.1], polygon[GRID.polygon.2], polygon[GRID.polygon.3], polygon[GRID.polygon.4], text[GRID.text.5], text[GRID.text.6], text[GRID.text.7], text[GRID.text.8], text[GRID.text.9])

3. What percent of voters are Independent but not swing voters?

• 24% are non-swinging Independents.

4. What percent of voters are Independent or swing voters?

• 47% are Independent and/or swing voters; 36% are Independent or swing voters but not both.

5. What percent of voters are neither Independent nor swing voters?

• 53% are neither Independent nor swing voters.

6. Is the event that someone is a swing voter independent of the event that someone is a political Independent?

• No, the probability of being a swing voter is 23% for all voters, but the probability of being a swing voter given being an independent is 31%. The probabilities would be the same if the two variables were independent.