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DA0-002 · Question #72

A data analyst calculated the average score per student without making any changes to the following table: Which of the following exploration techniques should the analyst have considered before calcu

The correct answer is A. Duplication. Before calculating an average, it is crucial to address data quality issues such as duplicate records to ensure accuracy.

Data Acquisition and Preparation

Question

A data analyst calculated the average score per student without making any changes to the following table:

Which of the following exploration techniques should the analyst have considered before calculating the average?

Options

  • ADuplication
  • BRedundancy
  • CBinning
  • DGrouping

How the community answered

(23 responses)
  • A
    87% (20)
  • B
    4% (1)
  • C
    4% (1)
  • D
    4% (1)

Why each option

Before calculating an average, it is crucial to address data quality issues such as duplicate records to ensure accuracy.

ADuplicationCorrect

Duplication can inflate the count and sum of values, leading to an inaccurate or skewed average by counting the same entry multiple times.

BRedundancy

Redundancy is a broader concept that may include duplication but is not the most precise data exploration technique to address before averaging.

CBinning

Binning is a data transformation technique used to group data into intervals, not a pre-calculation cleaning step for averages.

DGrouping

Grouping is an aggregation technique to summarize data by categories, not a technique to address data quality issues before calculating an overall average.

Concept tested: Data quality and preprocessing-duplication

Source: https://learn.microsoft.com/en-us/power-query/remove-duplicates

Topics

#Data Quality#Duplicate Data#Data Preprocessing#Exploratory Data Analysis

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