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Choose an option to check your answer.
A.
By recursively combining suffix items with frequent patterns in conditional trees
B.
By testing random itemsets
C.
By fitting a classifier for each item
D.
By sorting confidence values only
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Correct Answer: A. By recursively combining suffix items with frequent patterns in conditional trees
Explanation:
The algorithm mines from shorter suffix-based conditional structures.
Each recursive step expands valid frequent itemsets.
Choose an option to check your answer.
A.
A decision tree using conditional probabilities
B.
A tree storing only infrequent items
C.
A random subset of the original tree
D.
An FP-tree built from the conditional pattern base of a suffix item
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Correct Answer: D. An FP-tree built from the conditional pattern base of a suffix item
Explanation:
It represents frequent prefixes associated with a chosen suffix.
Recursive mining extends those prefixes into larger frequent patterns.
Choose an option to check your answer.
A.
All transactions not containing the item
B.
The set of class labels predicted by the item
C.
The collection of prefix paths leading to a selected item
D.
A matrix of pairwise distances
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Correct Answer: C. The collection of prefix paths leading to a selected item
Explanation:
Prefix paths summarize contexts in which the suffix item appears.
Their counts support construction of a conditional FP-tree.
Choose an option to check your answer.
A.
To store target labels
B.
To link all nodes containing the same item
C.
To rank classifiers by accuracy
D.
To calculate Euclidean distance
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Correct Answer: B. To link all nodes containing the same item
Explanation:
Header links allow efficient traversal of an item's occurrences across the tree.
They are used to construct conditional pattern bases.
Choose an option to check your answer.
A.
An item label, a count, and links within the tree structure
B.
A class probability only
C.
A continuous prediction
D.
A complete confusion matrix
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Correct Answer: A. An item label, a count, and links within the tree structure
Explanation:
The count records how many transactions share the represented prefix.
Links connect nodes to parents, children, and same-item occurrences.
Choose an option to check your answer.
A.
Alphabetically only
B.
By ascending confidence
C.
Randomly for every transaction
D.
By descending global support
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Correct Answer: D. By descending global support
Explanation:
A common global order allows transactions to share prefixes.
Descending frequency generally maximizes compression.
Choose an option to check your answer.
A.
All frequent items
B.
Every item appearing in more than one transaction
C.
Items that do not meet minimum support
D.
The transaction identifier only
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Correct Answer: C. Items that do not meet minimum support
Explanation:
Infrequent items cannot belong to a frequent itemset.
Removing them reduces the tree and preserves relevant pattern information.
Choose an option to check your answer.
A.
One for every possible itemset
B.
Two
C.
Exactly one in all implementations
D.
No scans
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Correct Answer: B. Two
Explanation:
The first scan finds frequent items and their order.
The second inserts filtered, ordered transactions into the tree.
Choose an option to check your answer.
A.
It mines frequent patterns without generating a large candidate set
B.
It requires labeled class data
C.
It computes only one-itemsets
D.
It never scans the database
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Correct Answer: A. It mines frequent patterns without generating a large candidate set
Explanation:
FP-growth compresses transactions into an FP-tree and mines the structure recursively.
This avoids Apriori's candidate explosion.
Choose an option to check your answer.
A.
Training accuracy versus test accuracy
B.
Bias versus label cost
C.
Tree depth versus margin size
D.
Pattern coverage versus computational and interpretive complexity
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Correct Answer: D. Pattern coverage versus computational and interpretive complexity
Explanation:
Lower support finds more and rarer patterns but increases workload and output volume.
Higher support is efficient but may overlook important associations.
Choose an option to check your answer.
A.
All rejected candidates
B.
Only low-confidence rules
C.
The frequent itemsets from the current level
D.
The class confusion matrix
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Correct Answer: C. The frequent itemsets from the current level
Explanation:
Lk is joined to form candidates Ck+1.
Infrequent candidates do not contribute because their supersets cannot be frequent.
Choose an option to check your answer.
A.
Frequent subsets guarantee confidence one
B.
Any infrequent subset proves the candidate cannot meet minimum support
C.
Subsets determine class labels
D.
All subsets must have equal support
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Correct Answer: B. Any infrequent subset proves the candidate cannot meet minimum support
Explanation:
This is the candidate prune step based on anti-monotonicity.
It prevents counting candidates that cannot possibly be frequent.