CHAPTER 10 EXERCISES

Chapter 10 Single Sample t-Test

10.1 Preliminary Data Exploration

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   313.2   323.5   335.2   337.1   350.3   366.8

##  Time-Series [1:468] from 1959 to 1998: 315 316 316 318 318 ...

10.1 Preliminary Data Exploration

with(temp.data, t.test(co2, mu = 338))

## 
##  One Sample t-test
## 
## data:  co2
## t = -1.3681, df = 467, p-value = 0.1719
## alternative hypothesis: true mean is not equal to 338
## 95 percent confidence interval:
##  335.6941 338.4130
## sample estimates:
## mean of x 
##  337.0535

10.2.2 Example: Reject the Null

with(temp.data, t.test(co2, mu = 321))

## 
##  One Sample t-test
## 
## data:  co2
## t = 23.205, df = 467, p-value < 2.2e-16
## alternative hypothesis: true mean is not equal to 321
## 95 percent confidence interval:
##  335.6941 338.4130
## sample estimates:
## mean of x 
##  337.0535