Week 16- R studio

Question 1

What is the as.factor function and how do you use it?

Answer 1

When you want to convert the data type of a variable to a factor/categorical variable.

studytwo$ETHNICITY <- as.factor(studytwo$ETHNICITY)
summary(studytwo)

Question 2

How to see an overview of the data

Answer 2

head(studytwo)
summary(studytwo)

Question 3

How do you do a histogram (using a ggplot)

Answer 3

ggplot(data = studytwo, aes(x = mean.acc)) + geom_histogram()

Question 4

What is a binwidth and how do you add it onto a calculation?

Answer 4

We adjust binwidth typically to improve the appearance of the plot.
ggplot(data = studytwo, aes(x = SHIPLEY)) + geom_histogram(binwidth = 0.1)

Question 5

How to edit the colour of histogram theme?

Answer 5

ggplot(data = studytwo, aes(x = SHIPLEY)) +
geom_histogram(binwidth = 0.5) +
theme_bw()

Question 6

How to edit the labels of the histogram

Answer 6

ggplot(data = studytwo, aes(x = SHIPLEY)) +
geom_histogram(binwidth = 0.5) +
theme_bw() +
labs(x = “SHIPLEY”, y = “number of”)

Question 7

How do you create a scatterplot examining the association between variables?

Answer 7

ggplot(data = studytwo, aes(x = SHIPLEY, y = HLVA)) +
geom_point()

Question 8

How to change the appearance of a ggplot- alpha, size, colour, theme, labels

Answer 8

ggplot(data = studytwo, aes(x = HLVA, y = mean.self)) +
geom_point(alpha = 0.5, size = 2, colour = purple) +
theme_bw() +
labs(x = “HLVA”, y = “mean self rated accuracy”)

Question 9

How would you code a correlation test?

Answer 9

cor.test(studytwo$HLVA, studytwo$mean.acc, method = “pearson”, alternative = “two.sided”)