Next: Exercise 8.2 Up: No Title Previous: Exercise 7.3

# Exercise 8.1

1.
Obtain a comparison dotplot of the two samples (X and Y) below. Let T be the number of time a Y beats a X. Under the null hypothesis, what do you expect T to be? Next compute T.
```      X    78    108    121    123    127    140    141
Y   104    107    119    124    135    136
```
(Ans: T= 17).
2.
Below are the batting averages of the switch hitters and the left-handed hitters from the baseball data set. Obtain a comparison dotplot. Dotplot the two samples. Let T be the number of time an average of a left-handed hitter is bigger than the average of a switch-hitter. Under the null hypothesis, what do you expect T to be? Next compute T .
```      Switch  .212   .218   .236   .242   .251   .251   .254   .261   .270  .282
Left   .238   .271   .279   .283   .284   .290   .300   .303
```
(Ans: T = 71).
3.
Consider the following samples of Italian and Etruscan skull sizes. Let T be the number of time an Etruscan skull size is bigger than an Italian skull size. Under the null hypothesis, what do you expect T to be? Next compute T. It's easier if you sort the samples first!
```      Ital.  134    132    126    134    131    130    130    125    132    126
Etru.  141    145    145    146    142    126    144    146    154    149    143     131
```
4.
Below are the batting averages of the right-handed hitters and the left-handed hitters from the baseball data set. Dotplot the two samples. Let T be the number of times an average of a left-handed hitter is bigger than the average of a right-handed hitter. Under the null hypothesis, what do you expect T to be? Next compute T .
```      Right   .225   .238   .239   .243   .244   .245   .262   .271   .271
.274   .274   .276   .282   .286   .286

Left    .238   .271   .279   .283   .284   .290   .300   .303     240
```
5.
Did Manuel I shortchange the people by having less silver in in later days mintings? Try to answer this question by comparing the following two data sets (use comparison boxplots). Let T be the number of times a First minting has a higher percentage than a Fourth minting. Under the null hypothesis, what do you expect T to be? Next compute T .
```      First:     5.9  6.8   6.4  7.0  6.6  7.7  7.2  6.9  6.2
Fourth     5.3  5.6   5.5  5.1  6.2  5.8  5.8
```

Next: Exercise 8.2 Up: No Title Previous: Exercise 7.3

2000-08-26