Data Cleansing Quiz

What is the primary purpose of data cleansing in machine learning?

• To visualize data

• To analyze data trends

• To store data efficiently

• To prepare data for training models

Which function in Pandas is used to check for null values in a dataframe?

• dropna()

• fillna()

• isnull()

• isna()

What does the fillna() function do in a Pandas dataframe?

• Counts the number of NaN values

• Replaces NaN values with specified values

• Removes rows with NaN values

• Normalizes the data

What is the result of using the dropna() function?

• It checks for duplicate rows

• It replaces NaN values with the mean

• It removes all rows containing NaN values

• It fills NaN values with zeros

Which method is used to identify duplicate rows in a dataframe?

• isnull()

• fillna()

• duplicated()

• drop_duplicates()

What does the MinMaxScaler class do in data normalization?

• It identifies duplicate rows

• It removes outliers from the dataset

• It scales values to a specific range

• It checks for null values

What is an outlier in a dataset?

• A missing value in the dataset

• A value that is distant from other observed points

• A duplicate entry in the dataset

• A value that is similar to others

What is the purpose of Tukey's Fences in data analysis?

• To remove duplicate rows

• To fill NaN values

• To identify outliers based on IQR

• To normalize data

What does the Z-score method measure?

• The number of NaN values

• The average of a dataset

• The distance of a data point from the mean

• The range of values in a dataset

Which of the following is NOT a method for handling NaN values?

• Normalizing data

• Replacing with mean

• Filling with zeros

• Removing rows