Perform Data Exploration DA0-001 Practice Questions (Page 3)

Questions 11–15

1. 11foundation · easy

   An analyst finds an outlier in a dataset that is due to a data entry error. What is the most appropriate action to manage this outlier?

   • AKeep the outlier as is
   • BCorrect the error if possible, otherwise remove the record
   • CReplace the outlier with the mean of the column
   • DIgnore the outlier and proceed with analysis
   Reveal Solution Discussion Select an answer first
2. 12foundation · easy

   When resolving duplicate records, why is it important to verify that the duplicates are truly identical before removal?

   • ATo ensure the dataset is large enough for analysis
   • BTo confirm that the duplicates are outliers
   • CTo check if the duplicates contain missing values
   • DTo avoid accidentally removing unique records that share some fields
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4. 13application · medium

   An e-commerce analyst is reviewing a product order dataset. The analyst suspects that some orders were recorded twice due to a system glitch. The dataset has an 'order_id' column that should be unique. What is the most efficient way to identify duplicate orders?

   • ACalculate the average order amount and flag orders above the average.
   • BSort the dataset by 'order_id' and visually scan for repeats.
   • CGroup by 'order_id' and count the number of records in each group.
   • DRemove all rows where 'order_id' appears more than once.
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5. 14application · medium

   A database administrator finds that a customer table has duplicate records where the same customer appears with slightly different spellings of their name (e.g., 'Jon Smith' and 'John Smith') but the same phone number. The administrator needs to consolidate these records. What is the best approach?

   • ADelete one of the records arbitrarily.
   • BKeep both records because they have different names.
   • CMerge the records, keeping the most complete information from each.
   • DReplace both names with a standard version, such as 'John Smith'.
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6. 15application · medium

   A data analyst is exploring a dataset of test scores. The analyst finds a few scores that are much lower than the rest, and investigation reveals they are data entry errors (e.g., a score of 2 instead of 82). What is the most appropriate action?

   • AReplace the erroneous values with the mean test score.
   • BRemove the erroneous records from the dataset.
   • CKeep the erroneous values because they are part of the original data.
   • DCorrect the data entry errors if the true values can be determined from source documents.
   Reveal Solution Discussion Select an answer first