Chi-squared test in R Programming - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to perform a chi-squared test on the table 'data_table'.

R Programming

result <- chisq.test([1])

Drag options to blanks, or click blank then click option'

Amatrix()

Bdata.frame

Cdata_table

Dtable()

Attempts:

3 left

💡 Hint

Common Mistakes

Passing a function call like matrix() instead of the table variable.

Using data.frame which is not a contingency table.

The function chisq.test() requires a contingency table as input. Here, data_table is the correct variable representing the table.

2fill in blank

medium

Complete the code to extract the p-value from the chi-squared test result stored in 'result'.

R Programming

p_value <- result$[1]

Drag options to blanks, or click blank then click option'

Astatistic

Bobserved

Cparameter

Dp.value

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'statistic' which gives the test statistic, not the p-value.

Using 'parameter' or 'observed' which are different parts of the result.

The p-value of the chi-squared test is stored in the p.value element of the result object.

3fill in blank

hard

Fix the error in the code to correctly create a contingency table from vectors 'group' and 'outcome'.

R Programming

table_data <- [1](group, outcome)

Drag options to blanks, or click blank then click option'

Atable

Bmatrix

Ccbind

Ddata.frame

Attempts:

3 left

💡 Hint

Common Mistakes

Using cbind which just binds columns without counting.

Using data.frame or matrix which do not create frequency tables.

The table() function creates a contingency table from categorical vectors.

4fill in blank

hard

Fill both blanks to perform a chi-squared test with continuity correction disabled on 'table_data'.

R Programming

result <- chisq.test([1], [2]FALSE)

Drag options to blanks, or click blank then click option'

Atable_data

Bcorrect =

Ccorrect=

Ddata_table

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'correct = ' with spaces around the equals sign.

Passing wrong variable names like 'data_table'.

The first argument is the contingency table variable table_data. The parameter to disable continuity correction is correct=FALSE with no space around the equals sign.

5fill in blank

hard

Fill all three blanks to create a table from 'gender' and 'smoking' vectors, perform a chi-squared test, and extract the test statistic.

R Programming

tab <- [1](gender, smoking)
result <- chisq.test([2])
st <- result$[3]

Drag options to blanks, or click blank then click option'

Atable

Btab

Cstatistic

Ddata.frame

Attempts:

3 left

💡 Hint

Common Mistakes

Using data.frame instead of table.

Passing wrong variable names or extracting wrong elements.

First, create the contingency table with table(). Then pass that table variable tab to chisq.test(). Finally, extract the test statistic with statistic.