Bryson_BIOL3000_Quiz1_2

BIOL3000 Quiz1 Hannah Bryson Mon Jan 29 10:18:25 2024 EST Instructions: Please do not print the whole data as it is long, jut print head(data) to see first few rows only. Please change the name of your file with your last name as lastname_Biostat_Quiz1.Rmd . Question 1 You need to use R to answer all questions • Read the builtin dataset called ‘iris’ (name it as A) in R. The data set gives the measurements in centimeters of the variables sepal length and width and petal length and width, respectively, for 50 flowers from each of 3 species of iris. The species are Iris setosa, versicolor, and virginica. A = iris head (A) ## Sepal.Length Sepal.Width Petal.Length Petal.Width Species ## 1 5.1 3.5 1.4 0.2 setosa ## 2 4.9 3.0 1.4 0.2 setosa ## 3 4.7 3.2 1.3 0.2 setosa ## 4 4.6 3.1 1.5 0.2 setosa ## 5 5.0 3.6 1.4 0.2 setosa ## 6 5.4 3.9 1.7 0.4 setosa • If any columns have missing/blank values, first replace them by NA and then list the columns that have NA values. is.na (A) <- A == colnames (A)[ apply ( is.na (A), 2 , any)] head (A) ## Sepal.Length Sepal.Width Petal.Length Petal.Width Species ## 1 5.1 3.5 1.4 0.2 setosa ## 2 4.9 3.0 1.4 0.2 setosa ## 3 4.7 3.2 1.3 0.2 setosa ## 4 4.6 3.1 1.5 0.2 setosa ## 5 5.0 3.6 1.4 0.2 setosa ## 6 5.4 3.9 1.7 0.4 setosa • Add a new column named Sepal_Size in A. This new column uses the column named Sepal.Length. If Sepal.Length< 5, then the Sepal_Size is ‘small’, if Sepal.Length > 5 but smaller than 6.4, then the Sepal_Size is ‘medium’, and if the Sepal.Length > 6.4, then the Sepal_Size is ‘big’. Hint: use cut and breaks function.

B = data.frame (A) B $ Sepal_Size = cut (A $ Sepal.Length, breaks = c ( 0 , 5 , 6.4 , 20 ), labels = c ( 'small' , 'medium' , 'big' ), include.lowest = TRUE ) head (B) ## Sepal.Length Sepal.Width Petal.Length Petal.Width Species Sepal_Size ## 1 5.1 3.5 1.4 0.2 setosa medium ## 2 4.9 3.0 1.4 0.2 setosa small ## 3 4.7 3.2 1.3 0.2 setosa small ## 4 4.6 3.1 1.5 0.2 setosa small ## 5 5.0 3.6 1.4 0.2 setosa small ## 6 5.4 3.9 1.7 0.4 setosa medium * Using table function, find how many Sepal_Size are small, medium and big. Name the table as Tab1. Also, using species column and table function, find how many data are setosa, versicolor and virginica. Name the second table as Tab2. ```r Tab1=table(B$Sepal_Size) Tab1 ## ## small medium big ## 32 83 35 Tab2 = table (B $ Species) Tab2 ## ## setosa versicolor virginica ## 50 50 50 • Find the average, median and variance of the column Sepal.Length. Also find the 55th percentile of the column Sepal.Width. mean (B $ Sepal.Length) ## [1] 5.843333 median (B $ Sepal.Length) ## [1] 5.8

library (plotrix) pie3D (Tab2, labels= c ( 'short' , 'medium' , 'long' ), col= 2 : 6 , main= "Species Type" , radius= 2 , explode= 0.1 , labelcex= 1.0 )