Higher Applications RStudio Revision

Question 1

Which command imports a CSV file into R?

importing data

data = open(file)csv(data)data <− read.csv("file.csv")read.file(csv)

Question 2

Which command checks column names?

checking column names

columns dataread.names()labels(data, all)names(data)

Question 3

Write a command to find the mean of data$score.

summary statistics

Your answer

Question 4

Which phrase is best for a project conclusion?

project write-up

This proves forever...This suggests...The graph is prettyThe data is always perfect

Question 5

What does correlation not prove?

correlation

DirectionA numerical valueCausationAssociation

Question 6

Two classes have mean score 75. The table describes class A; class B has SD 8.8 marks. Which conclusion about consistency is justified? RStudio summary output: variable: score, mean: 75, median: 77, sd: 5.8.

interpreting output

Every pupil in class A scored higher than every pupil in class BBoth classes have identical spreads because their means matchClass B is more consistent because its SD is largerClass A is more consistent, but its smaller SD does not imply every pupil scored nearer the mean

Question 7

Which command fits a linear regression model?

linear regression

read.csv(y ~ x)hist(y ~ x)lm(y ~ x, data = data)cor.only(y, x)

Question 8

Which command can produce a confidence interval for a mean?

confidence intervals

names(x)plot(x)read.csv(x)t.test(x)$conf.int

Question 9

Which option is needed for a paired t-test?

t-tests

paired = TRUEprop = TRUEpair = maybehist = TRUE

Question 10

Which command compares two proportions?

proportion tests

t.test(paired = TRUE)boxplot()prop.test()sd()

Question 11

R says object not found. What is a likely issue?

RStudio errors

The p-value is smallThe mean is too largeThe chart has a titleA misspelt or unloaded object

Question 12

What should a project limitation do?