1. The chart below gives percentage of counties in US that use many methods for recording votes in 1980 & 2002. Set up side-by-side bar charts by year using instruction for side-by-side charts in the Class Notes Conference.
Method |
1980 |
2002 |
Punch cards |
18.5 |
15.5 |
Lever machines |
36.7 |
10.6 |
Paper ballots |
40.7 |
10.5 |
Optical scan |
0.8 |
43 |
Electronic |
0.2 |
16.3 |
Mixed |
3.1 |
4.1 |
2. The following are a sample of weights of nine jars of peanut butter,
7.697.72 7.80 7.86 7.90 7.94 7.97 8.06 8.09
a) Evaulate the median weight.
b) Evaulate the standard deviation of sample.
c) Employ PHStat to make a box-whisker plot. If PHSTAT has yet to be installed, compute Xmin, Xmax, Q_{1}, Q_{3} and median using equation in Class Notes-Quartiles, Percentile and Dectiles.
d) Are there outliers? An outlier value is stated as usually large or small according to expression:
Outlier > Q3 + 1.5 (Q3 - Q1) or,
Outlier < Q1 - 1.5 (Q3 - Q1)