CompTIA DA0-001 Online Practice Questions and Exam Preparation

CompTIA DA0-001 Online Questions & Answers

• Question 231:

  Which one of the following would not normally be considered a summary statistic?

  A. z-score.
  B. Mean.
  C. Variance.
  D. Standard deviation.
  A. z-score.

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  Explanation

  Simply put, a z-score (also called a standard score) gives you an idea of how far from the mean a data point is. But more technically it's a measure of how many standard deviations below or above the population mean a raw score is. A z-score can be placed on a normal distribution curve.

• Question 232:

  A data analyst is working for a shipping company and calculating the volume of boxes according to the following formula: volume = height ?width ?depth. Which of the following variable types describes volume?

  A. Derived
  B. Normalized
  C. Concatenated
  D. Aggregated
  A. Derived

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  Explanation

• Question 233:

  Joe. an analyst. tests the loading time on a dashboard he is preparing to go live and finds it is slower than he would like. Which of the following must occur to decrease the loading time?

  A. Deploy the dashboard to production.
  B. Change the field definitions.
  C. Update the dashboard subscribers.
  D. Optimize the dashboard.
  D. Optimize the dashboard.

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  Explanation

  Optimizing the dashboard is the process of improving its performance and reducing its loading time by applying various techniques and best practices. Some of the common ways to optimize a dashboard are: Reducing the size and complexity of the data model, such as removing unnecessary columns, aggregating data at the source, or using data compression techniques. Leveraging caching strategies, such as setting appropriate cache refresh intervals or utilizing Power BI's built-in caching mechanisms, to minimize data retrieval delays. Utilizing query folding, direct query, or live connection to enhance data processing efficiency and enable real-time data updates. Optimizing DAX queries, such as avoiding nested calculations, using variables, or simplifying measures, to improve data calculation speed. Reducing visualizations and calculations, such as using fewer or simpler charts, filters, or parameters, to speed up dashboard rendering. Evaluating the impact of custom visuals on dashboard load time and avoiding or replacing those that are slow or inefficient. Applying aggregation and summarization techniques, such as using extract filters, context filters, or level of detail expressions, to reduce the amount of data displayed on the dashboard. Troubleshooting and resolving any issues that may cause slow dashboard load, such as network latency, server overload, or hardware limitations.

• Question 234:

  A data analyst has been asked to organize the table below in the following ways:

  By sales from high to low

  By state in alphabetic order

  

  Which of the following functions will allow the data analyst to organize the table in this manner?

  A. Conditional formatting
  B. Grouping
  C. Filtering
  D. Sorting
  D. Sorting

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  Explanation

  Sorting is the function that will allow the data analyst to organize the table in the desired manner. Sorting means arranging the data in a specific order, such as ascending or descending, based on one or more criteria. Sorting can be applied to

  any column in the table, such as sales or state.

  References:

  CompTIA Data+ Certification Exam Objectives, page 11

• Question 235:

  An analyst needs to summarize the number of people in Chicago in 2022 using the following set of data:

  

  Which of the following steps should the analyst use to provide results? (Select two).

  A. Aggregation
  B. Sorting
  C. Filtering
  D. Indexing
  E. Cleaning
  F. Replacing
  A. Aggregation
  C. Filtering

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  Explanation

• Question 236:

  A stakeholder wants to see daily sales targets organized in a dashboard by country, state, city, and ZIP Code.

  Which of the following delivery considerations must a data analyst take into account when creating the dashboard?

  A. Variable formatting
  B. Drill-down capability
  C. Saved searches
  D. Access permissions
  B. Drill-down capability

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  Explanation

• Question 237:

  Which of the following is a best practice when updating a legacy data source?

  A. Placing old data in new fields
  B. Keeping only the most recent data
  C. Creating a codebook to document field changes
  D. Removing the data source from production
  C. Creating a codebook to document field changes

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  Explanation

  When updating a legacy data source, it is a best practice to create a codebook to document field changes. A codebook serves as a detailed guide and record of the data structure, definitions, and any transformations or modifications made to the data fields. This documentation is crucial for maintaining data integrity, ensuring consistency, and facilitating future data use and understanding. It provides a reference that can be invaluable for data analysts, developers, and any stakeholders who need to work with the data. Creating a codebook is preferred over placing old data in new fields, which can lead to confusion and data integrity issues. Keeping only the most recent data may result in the loss of valuable historical information. Removing the data source from production is not a practice related to updating data but rather to retiring a data.

  References: Legacy Data Migration: A Comprehensive Guide | OpenGeeksLab How to Successfully Complete Legacy Database Migration Methods for Saving and Integrating Legacy Data - DATAVERSITY Legacy Data Digitization - Learn The Best Practices

• Question 238:

  An analyst is building a new dashboard for a user. After an initial conversation with the user. the analyst created a mock-up of the dashboard.

  Which of the following best explains why the analyst created the mock-up?

  A. To identify the dimensions and measures
  B. To send to the client after deploying the dashboard to production
  C. To confirm important details before dashboard development begins
  D. To receive client approval for the final dashboard design
  C. To confirm important details before dashboard development begins

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  Explanation

  Answer:

  C. To confirm important details before dashboard development begins.

  A dashboard mockup is a prototype of a finished dashboard directly in the product. It is a way to visualize the layout, design, and functionality of the dashboard before it is built with real data and code. A dashboard mockup can help the

  analyst to confirm important details with the user, such as the business objectives, the key performance indicators, the data sources, the filters, the charts, and the interactivity. By creating a dashboard mockup, the analyst can get immediate

  feedback and validation from the user, and avoid wasting time and resources on developing a dashboard that does not meet the user's expectations or needs.

• Question 239:

  You are working with a dataset and want to change the names of categories that you used for different types of books.

  What term best describes this action?

  A. Recording.
  B. Summarizing
  C. Aggregating.
  D. Filtering.
  A. Recording.

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  Explanation

  The term that best describes the action of changing the names of categories that you used for different types of books is recoding. Recoding is a process of transforming or modifying the values of a variable or a category to make them more

  meaningful, consistent, or accurate. For example, you can recode the names of book genres from "Fiction", "Non-Fiction", "Biography", etc. to "FIC", "NF", "BIO", etc. to make them shorter and easier to use.

  Recoding Data - SPSS Tutorials - LibGuides at Kent State University

• Question 240:

  Which of the following techniques should an analyst use to analyze a data set to get a snapshot of basic measures of central tendency?

  A. Forecasting
  B. Trend analysis
  C. Gap analysis
  D. Descriptive statistics
  D. Descriptive statistics

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  Explanation