CompTIA DA0-001 Online Practice Questions and Exam Preparation

CompTIA DA0-001 Online Questions & Answers

• Question 171:

  During data cleansing, an analyst conducts measures of central tendency on a data set.

  Which of the following data is the analyst attempting to identify?

  A. Duplicate
  B. Missing
  C. Outlying
  D. Invalid
  C. Outlying

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  Explanation

• Question 172:

  A financial analyst is creating a daily billing report for a company. One night, the company's data warehouse did not update the data, which caused the data to be reported incorrectly the next day.

  Which of the following documentation elements should the analyst add to catch this error?

  A. Version number
  B. Data refresh
  C. Frequently asked questions tab
  D. Summary
  B. Data refresh

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  Explanation

  A data refresh is a documentation element that indicates when the data was last updated or refreshed from the source. A data refresh can help the analyst to catch the error of the data warehouse not updating the data, as it will show a discrepancy between the expected and actual date of the data update. A data refresh can also help the users of the report to verify the timeliness and accuracy of the data, and to avoid making decisions based on outdated or incorrect data

• Question 173:

  Q3 2020 has just ended, and now a data analyst needs to create an ad-hoc sales report that demonstrates how well the Q3 2020 promotion went versus last year's Q3 promotion. Which of the following date parameters should the analyst use?

  A. 2019 vs. YTD 2020
  B. Q3 2019 vs. Q3 2020
  C. YTD 2019 vs. YTD 2020
  D. Q4 2019 vs. Q3 2020
  B. Q3 2019 vs. Q3 2020

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  Explanation

  The date parameters that the analyst should use are Q3 2019 vs. Q3 2020, as this will allow the analyst to compare the sales performance of the Q3 2020 promotion with the same period of last year. This will help to eliminate any seasonal or

  cyclical effects that might affect the sales data. The other options are not relevant for this purpose, as they either compare different quarters or different years.

  CertMaster Practice for Data+ Exam Prep - CompTIA

• Question 174:

  A user imports a data file into the accounts payable system each day. On a regular basis. the field input is not what the system is expecting. so it results in an error for the row and a broken import process. To resolve the issue, the user opens the file, finds the error in the row, and manually corrects it before attempting the import again. The import sometimes breaks on subsequent attempts though.

  Which of the following changes should be made to this process to reduce the number of errors?

  A. Delete all incorrect inputs and upload the corrected file.
  B. Have the user manually review the file for data completeness before loading it
  C. Create a data field to data type validator to run the file through prior to import.
  D. Spot-check the file prior to import to catch and correct field errors.
  C. Create a data field to data type validator to run the file through prior to import.

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  Explanation

  A data field to data type validator is a tool or a process that checks if the data in each field of a file matches the expected data type, such as text, number, date, etc. A data field to data type validator can help to identify and correct any errors or inconsistencies in the data before importing it into the accounts payable system. This would reduce the number of errors and broken imports, as well as save time and effort for the user.

• Question 175:

  A data analyst needs to present the results of an online marketing campaign to the marketing manager. The manager wants to see the most important KPIs and measure the return on marketing investment.

  Which of the following should the data analyst use to BEST communicate this information to the manager?

  A. A real-time monitor that allows the manager to view performance the day the campaign was launched
  B. A sell-service dashboard that allows the manager to look at the company's annual budget performance
  C. A spreadsheet of the raw data from all marketing campaigns and channels
  D. A summary with statistics, conclusions, and recommendations from the data analyst
  D. A summary with statistics, conclusions, and recommendations from the data analyst

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  Explanation

  The option that the data analyst should use to best communicate the information to the manager is a summary with statistics, conclusions, and recommendations from the data analyst. A summary is a concise and clear way of presenting the

  main findings and insights from the data analysis report. A summary should include relevant statistics that support the conclusions and recommendations from the data analyst. A summary should also highlight the most important KPIs and

  measure the return on marketing investment in relation to the objectives of the online marketing campaign. The other options are not as effective as using a summary to communicate the information to the manager, as they either provide too

  much or too little information or do not address the manager's needs or expectations. A real-time monitor may provide too much information that can be overwhelming or distracting for the manager who wants to see only the most important

  KPIs and measure the return on marketing investment. A self-service dashboard may provide too little information that can be insufficient or unclear for the manager who wants to see some guidance and interpretation from the data analyst. A

  spreadsheet of raw data may provide irrelevant or inaccurate information that can be confusing or misleading for the manager who wants to see some analysis and insights from the data analyst.

  [How to Write an Executive Summary for Your Data Analysis Report - Towards Data Science]

• Question 176:

  Samantha needs to share a list of her organization's top 50 customers with the VP of sales.

  She would like to include the name of the customer, the business they represent, their contact information, and their total sales over the past year.

  The VP does not have any specialized analytics skills or software but would like to make some personal notes on the dataset.

  What would be the best tool for Samantha to use to share this information?

  A. Power BI.
  B. Microsoft Excel.
  C. Minitab.
  D. SAS.
  B. Microsoft Excel.

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  Explanation

  Microsoft Excel.

  This scenario presents a very simple use case where the business leader needs a dataset in an easy-to-access form and will not be performing any detailed analysis. A simple spreadsheet, such as Microsoft Excel, would be the best tool for

  this job. There is no need to use a statistical analysis package, such as SAS or Minitab, as this would likely confuse the VP without adding any value. The same is true of an integrated analytics suite, such as Power BI.

• Question 177:

  Given the image below:

  

  Which of the following file formats is depicted?

  A. JSON
  B. CSV
  C. XML
  D. HTML
  A. JSON

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  Explanation

  The image depicts a snippet of code in the JSON format, which stands for JavaScript Object Notation. JSON is a lightweight data-interchange format that is easy for humans to read and write and easy for machines to parse and generate. It is

  based on a subset of the JavaScript Programming Language and is commonly used to transmit data in web applications.

  CSV, or Comma-Separated Values, is a simple file format used to store tabular data, such as a spreadsheet or database. It uses commas to separate values. XML, or eXtensible Markup Language, is a markup language that defines a set of

  rules for encoding documents in a format that is both human-readable and machine-readable.

  HTML, or HyperText Markup Language, is the standard markup language for documents designed to be displayed in a web browser.

  References:

  JSON.org - Introducing JSON

  W3Schools - JSON Introduction

  Mozilla Developer Network - JSON

• Question 178:

  What SQL command is used to delete an entire table from a database?

  A. DROP.
  B. MODIFY.
  C. DELETE.
  D. ALTER.
  A. DROP.

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  Explanation

• Question 179:

  Which of the following is the best technique for transferring data from one database to another with some data manipulation?

  A. Application programming interfaces
  B. Delta load
  C. Extract, transform, load
  D. Export/import
  C. Extract, transform, load

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  Explanation

• Question 180:

  Which of the following roles is responsible for ensuring an organization's data quality, security, privacy, and regulatory compliance?

  A. Data owner.
  B. Data steward.
  C. Data custodian.
  D. Data processor.
  B. Data steward.

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  Explanation

  Correct answer

  B. Data steward.

  A data steward is responsible for leading an organization's data governance activities, which include data quality, security, privacy, and regulatory compliance.