Question

Statistics, R-Studio

Researchers are interested in the effect of a certain nutrient on the growth rate of plant seedlings. Using a hydroponics grow procedure that utilized water containing the nutrient, they planted six tomato plants and recorded the heights of each plant 14 days after germination. Those heights, measured in millimeters, were as follows: 55.5, 60.3, 60.6, 62.1, 65.5, 69.2.

Use Rstudio to plot the t distribution graph of the six given heights with a 95% confidence interval.

Answer 1

> X=c(55.5, 60.3, 60.6, 62.1, 65.5, 69.2)
> summary(X)
   Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
  55.50   60.38   61.35   62.20   64.65   69.20 
> # T-distribution graph
> t.test(X,mu=62.20, alternative="two.sided", conf.level = 0.95)

        One Sample t-test

data:  X
t = 0, df = 5, p-value = 1
alternative hypothesis: true mean is not equal to 62.2
95 percent confidence interval:
 57.25628 67.14372
sample estimates:
mean of x 
     62.2 

> boxplot(X)
> # Hence, the plot is given below and confidence interval is (57.26,67.14).