EMC EMC Certifications E20-007 Questions & Answers

• Question 161:

  A disk drive manufacturer has a defect rate of less than 1.0% with 98% confidence. A quality assurance team samples 1000 disk drives and finds 14 defective units. Which action should the team recommend?

  A. The manufacturing process should be inspected for problems.

  B. A larger sample size should be taken to determine if the plant is functioning properly

  C. A smaller sample size should be taken to determine if the plant is functioning properly

  D. The manufacturing process is functioning properly and no further action is required.

  Correct Answer: A

• Question 162:

  In the MapReduce framework, what is the purpose of the Map Function?

  A. It processes the input and generates key-value pairs

  B. It collects the output of the Reduce function

  C. It sorts the results of the Reduce function

  D. It breaks the input into smaller components and distributes to other nodes in the cluster

  Correct Answer: A

• Question 163:

  A data scientist is given an R data frame (i.e., empdata) with the following columns: Age Salary Occupation Education Gender The scientist wants 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

  Correct Answer: A

• Question 164:

  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

  Correct Answer: A

• Question 165:

  Before you build an ARMA model, how can you tell if your time series is weakly stationary?

  A. There appears to be a constant variance around a constant mean.

  B. The mean of the series is close to 0.

  C. The series is normally distributed.

  D. There appears to be no apparent trend component.

  Correct Answer: A

• Question 166:

  Which SQL OLAP extension provides all possible grouping combinations?

  A. CUBE

  B. ROLLUP

  C. UNION ALL

  D. CROSS JOIN

  Correct Answer: A

• Question 167:

  When would you use GROUP BY ROLLUP clause in your OLAP query?

  A. where all subtotals and grand totals are to be included in the output

  B. where only the subtotals are to be included in the output

  C. where only the grand totals are to be included in the output

  D. where only specific subtotals and grand totals for a combination of variables are to be included in the output

  Correct Answer: A

• Question 168:

  When would you use a Wilcoxson Rank Sum test?

  A. When you cannot make an assumption about the distribution of the populations

  B. When the data can easily be sorted

  C. When the populations represent the sums of other values

  D. When the data cannot easily be sorted

  Correct Answer: A

• Question 169:

  Which type of numeric value does a logistic regression model estimate?

  A. Probability

  B. A p-value

  C. Any integer

  D. Any real number

  Correct Answer: A

• Question 170:

  What is Hadoop?

  A. Java classes for HDFS types and MapReduce job management and HDFS

  B. Java classes for HDFS types and MapReduce job management and the MapReduce paradigm

  C. MapReduce paradigm and HDFS

  D. MapReduce paradigm and massive unstructured data storage on commodity hardware

  Correct Answer: A