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The following frequent 4-sequences were the only frequent 4-sequences generated by a candidate generation step:

<{1}{2}{3}{4}>
<{1}{2}{4}{5}>
<{1,2}{3,4>>
<{1,3}{4}{5}>
<{2}{3,4}{5}>
<{2}{3}{4}{5}>

a. Is it possible to merge <{1,2}{3,4;> and <{2}{3,4}{5}> and generate a 5-sequence? If yes, write down that sequence. If no, explain briefly.

User Chornge
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The a. Yes, it is possible to merge <\{1,2\}\{3,4}\> and <{2}{3,4}{5}\> and generate a 5-sequence:<\{1,2\}\{3,4\}\{5\}>. b. No, it is not possible to merge <\{1\}\{2\}\{3\}\{4\}> and <\{2\}\{3,4\}\{5\}\rangle. c. Yes, the candidate <{1}{2}{3}{4}{5}> will survive the pruning step.

It is possible to merge <\{1,2\}\{3,4}\> and <{2}{3,4}{5}\> and generate a 5-sequence:<\{1,2\}\{3,4\}\{5\}>

No, it is not possible to merge <\{1\}\{2\}\{3\}\{4\}> and <\{2\}\{3,4\}\{5\}\rangle and generate a 5-sequence.

This is because the two sequences have different lengths, and the order of events in a sequence matters.

Yes, the candidate <{1}{2}{3}{4}{5}> will survive the pruning step.

This is because it is a supersequence of two frequent 4-sequences, <{1}{2}{3}{4}> and <{2}{3}{4}{5}>.

In sequential pattern mining, a frequent sequence is a sequence of events that occurs in a dataset with a minimum support threshold.

The support of a sequence is the percentage of transactions in the dataset that contain the sequence.

The pruning step is a step in sequential pattern mining that removes candidate sequences that cannot be frequent.

A candidate sequence is a sequence that is generated by merging two frequent sequences.

In order for a candidate sequence to survive the pruning step, it must be a supersequence of two frequent sequences.

A supersequence of a sequence is a sequence that contains all of the events in the original sequence, in the same order.

In the example provided, the candidate sequence <{1}{2}{3}{4}{5}> is a supersequence of the two frequent 4-sequences <{1}{2}{3}{4}> and <{2}{3}{4}{5}>.

Therefore, it will survive the pruning step.

The following frequent 4-sequences were the only frequent 4-sequences generated by-example-1
User CopOnTheRun
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