Data Science

caret

Question 1
Marks : +2 | -2
Pass Ratio : 100%
Point out the correct statement.
Asymptotics are used for inference usually
Caret includes several functions to pre-process the predictor data
The function dummyVars can be used to generate a complete set of dummy variables from one or more factors
All of the mentioned
Explanation:
The function dummyVars takes a formula and a data set and outputs an object that can be used to create the dummy variables using the predict method.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Which of the following argument is used to set importance values?
scale
set
value
all of the mentioned
Explanation:
All measures of importance are scaled to have a maximum value of 100.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
varImp is a wrapper around the evimp function in the _______ package.
numpy
earth
plot
none of the mentioned
Explanation:
The earth package is an implementation of Jerome Friedman’s Multivariate Adaptive Regression Splines.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
Which of the following model sums the importance over each boosting iteration?
Boosted trees
Bagged trees
Partial least squares
None of the mentioned
Explanation:
gbm package can be used here.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
Which of the following can be used to impute data sets based only on information in the training set?
postProcess
preProcess
process
all of the mentioned
Explanation:
This can be done with K-nearest neighbors.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Which of the following function is a wrapper for different lattice plots to visualize the data?
levelplot
featurePlot
plotsample
none of the mentioned
Explanation:
featurePlot is used for data visualization in caret.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
caret does not use the proxy package.
True
False
Explanation:
caret uses the proxy package.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
Point out the correct statement.
findLinearColumns will also return a vector of column positions can be removed to eliminate the linear dependencies
findLinearCombos will return a list that enumerates dependencies
the function findLinearRows can be used to generate a complete set of row variables from one factor
none of the mentioned
Explanation:
For each linear combination, it will incrementally remove columns from the matrix and test to see if the dependencies have been resolved.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
The function preProcess estimates the required parameters for each operation.
True
False
Explanation:
predict.preProcess is used to apply them to specific data sets.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
Which of the following function can be used to identify near zero-variance variables?
zeroVar
nearVar
nearZeroVar
all of the mentioned
Explanation:
The saveMetrics argument can be used to show the details and usually defaults to FALSE.