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Nizamuddin Siddiqui has Published 2307 Articles

Nizamuddin Siddiqui
8K+ Views
To find the sum of squared values of an R data frame column, we can simply square the column with ^ sign and take the sum using sum function. For example, if we have a data frame called df that contains a column say V then the sum of squared ... Read More

Nizamuddin Siddiqui
4K+ Views
If the numeric values are being read as character then we need to convert them into numeric values by using the function as.numeric. For example, if we have a data frame called df that contains a column say x which has numerical values stored in character format then we can ... Read More

Nizamuddin Siddiqui
783 Views
To find the number of unique values for each column in data.table object, we can use uniqueN function along with lapply. For example, if we have a data.table object called DT that contains five columns each containing some duplicate values then the number of unique values in each of these ... Read More

Nizamuddin Siddiqui
2K+ Views
When we have a factor column in an R data frame that has two levels and multiple numerical columns then we can apply paired-test on this data frame but the data must be collected for same subjects, otherwise it will not be a paired data. The t.test application on the ... Read More

Nizamuddin Siddiqui
6K+ Views
To create a frequency column for categorical variable in an R data frame, we can use the transform function by defining the length of categorical variable using ave function. The output will have the duplicated frequencies as one value in the categorical column is likely to be repeated. Check out ... Read More

Nizamuddin Siddiqui
3K+ Views
To display p-value in stargazer output for linear regression model, we can use the report argument. For example, if we have a model called RegressionModel then to display the p-value with coefficients can be done by using the below command −stargazer(RegressionModel, type="text", report=("vc*p"))ExampleConsider the below data frame − Live Demox1Read More

Nizamuddin Siddiqui
198 Views
To create a blank column with randomization in an R data frame, we can use sample function and pass the blanks with single space. For example, if we want to create a vector say x that will be added in the data frame can be created by using the command ... Read More

Nizamuddin Siddiqui
200 Views
The combination of values with repetition is the combination where the values can be repeated when creating the combination. For example, if we have three values say 1 and 2 then the combination of these values with repetition will be as follows −1 1 2 1 1 2 2 2For ... Read More

Nizamuddin Siddiqui
3K+ Views
To find the sum of every n values in R data frame columns, we can use rowsum function along with rep function that will repeat the sum for rows. For example, if we have a data frame called df that contains 4 columns each containing twenty values then we can ... Read More

Nizamuddin Siddiqui
2K+ Views
When we have a factor column in an R data frame that has two levels and a numerical column then we can apply paired-test on this data frame but the data must be collected for same subjects, otherwise it will not be a paired data. The t.test application on the ... Read More