EMC E20-007 Online Practice Questions and Exam Preparation

EMC E20-007 Online Questions & Answers

• Question 41:

  When is a Wilcoxon Rank-Sum test used?

  A. When an assumption about the distribution of the populations cannot be made
  B. When the data can be easily sorted
  C. When the populations represent the sums of other values
  D. When the data cannot be easily sorted
  A. When an assumption about the distribution of the populations cannot be made

• Question 42:

  You have been assigned to do a study of the daily revenue effect of a pricing model of online transactions. All the data currently available to you has been loaded into your analytics database; revenue data, pricing data, and online transaction data. You find that all the data comes in different levels of granularity. The transaction data has timestamps (day, hour, minutes, seconds), pricing is stored at the daily level, and revenue data is only reported monthly. What is your next step?

  A. Report back to the business owner that the current data model does not support the business question.
  B. Interpolate a daily model for revenue from the monthly revenue data.
  C. Aggregate all data to the monthly level in order to create a monthly revenue model.
  D. Disregard revenue as a driver in the pricing model, and create a daily model based on pricing and transactions only.
  A. Report back to the business owner that the current data model does not support the business question.

• Question 43:

  Consider a database with 4 transactions: Transaction 1: {cheese, bread, milk} Transaction 2: {soda, bread, milk} Transaction 3: {cheese, bread} Transaction 4: {cheese, soda, juice} You decide to run the association rules algorithm where minimum support is 50%. Which rule has a confidence at least 50%?

  A. {cheese} => {bread}
  B. {juice} => {cheese}
  C. {milk} => {soda}
  D. {soda} => {milk}
  A. {cheese} => {bread}

• Question 44:

  What is the output format from the Map function of MapReduce?

  A. Key-value pairs
  B. Binary representation of keys concatenated with structured data
  C. Compressed index
  D. Unique key record and separate records of all possible values
  A. Key-value pairs

• Question 45:

  Refer to the Exhibit.

  

  You are going into a meeting where you anticipate your manager will have a question on your dataset. Specifically, your manager will want to know about customers that are classified as renters with a good credit status. In order to prepare for the meeting, you create a rule: RENTER => GOOD CREDIT. What is the confidence of this rule?

  A. 18%
  B. 41%
  C. 63%
  D. 73%
  C. 63%

• Question 46:

  A data scientist is given an R data frame, "empdata", with the columns Age, Salary, Occupation, Education, and Gender. The data scientist would like to examine only the Salary and Occupation columns for ages greater than 40. Which command extracts the appropriate rows and columns from the data frame?

  A. empdata[empdata$Age > 40, c("Salary", "Occupation")]
  B. empdata[c("Salary", "Occupation"), empdata$Age > 40]
  C. empdata[Age > 40, ("Salary", "Occupation")]
  D. empdata[, c("Salary", "Occupation")]$Age > 40
  A. empdata[empdata$Age > 40, c("Salary", "Occupation")]

• Question 47:

  How are window functions different from regular aggregate functions?

  A. Rows retain their separate identities and the window function can access more than the current row.
  B. Rows are grouped into an output row and the window function can access more than the current row.
  C. Rows retain their separate identities and the window function can only access the current row.
  D. Rows are grouped into an output row and the window function can only access the current row.
  A. Rows retain their separate identities and the window function can access more than the current row.

• Question 48:

  Refer to the exhibit.

  

  Click on the calculator icon in the upper left corner. An analyst is searching a corpus of documents for the topic "solid state disk". In the Exhibit, Table A provides the inverse document frequency for each term across the corpus. Table B provides each term's frequency in four documents selected from corpus. Which of the four documents is most relevant to the analyst's search?

  A. Document B
  B. Document A
  C. Document C
  D. Document D
  A. Document B

• Question 49:

  You have been assigned to run a Logistic Regression model for 100 countries each. All data is currently stored in a PostgreSQL database. Which tool/library should be used to produce these models with the least effort?

  A. MADlib
  B. Mahout
  C. RStudio
  D. HBase
  A. MADlib

• Question 50:

  What is the purpose of the process step "parsing" in text analysis?

  A. imposes a structure on the unstructured/semi-structured text for downstream analysis
  B. performs the search and/or retrieval in finding a specific topic or an entity in a document
  C. executes the clustering and classification to organize the contents
  D. computes the TF-IDF values for all keywords and indices
  A. imposes a structure on the unstructured/semi-structured text for downstream analysis