Question

Boxplot of yield Descriptives ale amount i Spraying Standard Scheme Mean: Deviation: 53.50 84.91 84.83 63.30 6.77 18.45 9.15 29.1 Spraying Scheme (b) The fruit yields observed are displayed in the figure below, where a separate boxplot is drawn for the observations from trees following the four different spraying schemes (i) Using the boxplots and the descriptive statistics provided below, describe the distributions of fruit yield for each of the different spraying schemes. (ii) Which spraying scheme do you think is the most successful? Give a reason for your answer (ii) Which spraying scheme do you think leads to the most consistent yield? Give a reason for your answer c) In order to explore the relationship between fruit yield and the age of a tree the correlation coefficient for this sample of trees is calculated to be 0.85. Interpret the meaning of this value in terms of this application 20 marks]

Answer 1

SolutionBi:

From boxplot we observe that 4 group means are different.

There are outliers for spray type B seen frommboxlot

spray A is negatively skewed

spray B is positively  skewed.

spray C is normally distributed.

spray D is positively skewed.

mean for spray type B is highest and mean for spray type A is least

mean(B)=84.91 and mean(A)=53.50

spread is highest for type A and least for type C.

sd(A)=6.77 and sd(D)=29.1

SolutionBi:

spray B is most successful a mean is highest and spread is least

Mean(B)=84.91 sd(B)=18.45

SolutionBi:

spray C is most consistent as mean =84.83 and sd(C)=9.15

spread is also less comparatively to mean

Solutionc:

r=0.85

There exists a strong positive relationship between fruit yield and age of tree .

as age of tree increases,fruit yield increases and viceversa.