Dell EMC Data Science and BigData Certification Questions and Answers

Question : Refer to the Exhibit.
You are working on creating an OLAP query that outputs several rows of with summary rows of
subtotals and grand totals in addition to regular rows that may contain NULL as shown in the
exhibit. Which function can you use in your query to distinguish the row from a regular row to a
subtotal row?


1. GROUPING
2. RANK
3. Access Mostly Uused Products by 50000+ Subscribers
4. ROLLUP



Correct Answer : Get Lastest Questions and Answer :

Explanation:





Question : Refer to the exhibit.
After analyzing a dataset, you report findings to your team:
1. Variables A and C are significantly and positively impacting the dependent variable.
2. Variable B is significantly and negatively impacting the dependent variable.
3. Access Mostly Uused Products by 50000+ Subscribers
After seeing your findings, the majority of your team agreed that variable B should be positively
impacting the dependent variable.
What is a possible reason the coefficient for variable B was negative and not positive?


1. The information gain from variable B is already provided by another variable
2. Variable B needs a quadratic transformation due to its relationship to the dependent variable
3. Access Mostly Uused Products by 50000+ Subscribers
4. Variable B needs a logarithmic transformation due to its relationship to the dependent variable



Correct Answer : Get Lastest Questions and Answer :

Explanation:





Question : Refer to the exhibit.
You have run a linear regression model against your data, and have plotted true outcome versus
predicted outcome. The R-squared of your model is 0.75. What is your assessment of the model?

1. The R-squared may be biased upwards by the extreme-valued outcomes. Remove them and
refit to get a better idea of the model's quality over typical data.
2. The R-squared is good. The model should perform well.
3. Access Mostly Uused Products by 50000+ Subscribers
see if the R-squared improves over typical data.
4. The observations seem to come from two different populations, but this model fits them both
equally well.



Correct Answer : Get Lastest Questions and Answer :

Related Questions

---

Question : In R, functions like plot() and hist() are known as what?

1. generic functions
2. virtual methods
3. Access Mostly Uused Products by 50000+ Subscribers
4. generic methods





Question : Review the following code:
SELECT pn, vn, sum(prc*qty)
FROM sale
GROUP BY CUBE(pn, vn)
ORDER BY 1, 2, 3;
Which combination of subtotals do you expect to be returned by the query?


1. (pn, vn)
2. ( (pn, vn), (pn) )
3. Access Mostly Uused Products by 50000+ Subscribers
4. ( (pn, vn) , (pn), (vn) , ( ) )



Question : In MADlib what does MAD stand for?


1. Machine Learning, Algorithms for Databases
2. Mathematical Algorithms for Databases
3. Access Mostly Uused Products by 50000+ Subscribers
4. Modular, Accurate, Dependable


Question : The web analytics team uses Hadoop to process access logs. They now want to correlate this
data with structured user data residing in their massively parallel database. Which tool should they
use to export the structured data from Hadoop?


1. Sqoop
2. Pig
3. Access Mostly Uused Products by 50000+ Subscribers
4. Scribe



Question : When would you prefer a Naive Bayes model to a logistic regression model for classification?


1. When some of the input variables might be correlated
2. When all the input variables are numerical.
3. Access Mostly Uused Products by 50000+ Subscribers
4. When you are using several categorical input variables with over 1000 possible values each.



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


1. The mean of the series is close to 0.
2. The series is normally distributed.
3. Access Mostly Uused Products by 50000+ Subscribers
4. There appears to be no apparent trend component