Figure 8.15 shows a graph of state senatorial elections in Philadelphia from 1982 through 1993. Table 8.14 shows the data (Democrat minus Republican) for the 21 elections preceding the disputed 1993 election. Estimate the regression model Y = α + βX + ε, where the dependent variable is the absentee ballots and the explanatory variable is the Election Day ballots. In the disputed 1993 election, the difference in the Election Day ballots was −564. Find a 95 percent prediction interval for the absentee ballots in 1993.

Is 1,025, the actual value for the absentee ballots, inside this prediction interval?

Table 8.14

Figure 8.15

Transcribed Image Text:

Election Day Absentee Election Day Absentee 26,427 346 65,862 378 15,904 282 -13,194 -829 42,448 223 56,100 394 19,444 593 700 151 71,797 572 11,529 -349 -1,017 -229 26,047 160 63,406 671 44,425 1,329 15,671 293 45,512 368 36,276 360 -5,700 -434. 36,710 306 51,206 391 21,848 401