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I'm writing a paper about data mining. When I find some pattern periodically occur in some dataset, should I say:

Repeated structures are found in the dataset.


Repeating structures are found in the dataset.

I find myself end up with both forms in my paper so I doubt I really understand the difference and know when to use which.

From the Ngrams both forms seem to be correct.

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Repeating structures are those with an inherent nature of exhibiting/ settling into such a structure. Repeated structures are those that are so constructed by intent. In the context, what is being referred to is a dataset with repeating structures, as you can see that they are "found," to be so, not being "built" to be so. – Kris Aug 29 '13 at 8:31
The verb has an intransitive implication in repeating and a transitive connotation in repeated. – Kris Aug 30 '13 at 6:25
up vote 1 down vote accepted

Since it is periodical, the correct term would be 'Repeating Structures' 'Repeated' could mean only once or twice not forming any pattern or having any significance as such.

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Periodicity exists in both repeated as well as repeating structures. – Kris Aug 29 '13 at 8:27
Repeated is not necessarily periodical. It could be but Repeating is a apt when you're talking of something periodical. – nette Aug 30 '13 at 6:08
Your two statements do not agree. Check again. – Kris Aug 30 '13 at 6:24

The 2nd one Repeating Structures is right.


This example builds on Example 8 to show what happens when you select a set of repeating structures with the "subPaths" constructor option.

It defines that Repeated structures is not right to write here.

Example 9

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I don't think your evidence supports your position. I would think that because the data set the OP refers to is most likely finite it could only contain repeated structures. Where as a fractal or a data stream would contain repeating structures. And once recorded as a data set those repeating structures become repeated structures. – Dan D. Aug 26 '13 at 7:40
in reference has same situation. then why they are not using repeated structure? – Java D Aug 26 '13 at 7:42
Clearly there is uncertainty in the usage and they unlike the OP don't care about it. – Dan D. Aug 26 '13 at 7:44

In this context, it would be futile to attempt to communicate any subtle or technical differences by using one of repeated or repeating rather than the other. That is, both have senses that might or might not apply, such as “Having been said or done again” and “Sequential” for repeated and “That repeats; repetitive” and “Of a decimal: recurring” for repeating. Regardless of which term you use, the reader is likely to conclude that some structure occurs several times in the data. If that is what you mean to say, I recommend using the term repeated because it merely communicates the fact that a structure occurred several times instead of allowing the interpretation that some structure that can repeat occurred, once or more.

For better specificity and precision, consider using different wordings (depending on the facts), such as:
• Some structures appear in the dataset more than once.
• Some structures appear in the dataset multiple times.
• All structures appear in the dataset more than once each.
• Every kind of structure appears in the dataset at least twice.
• Each structure recurs in the dataset infinitely often.
• No structure in the dataset is a singleton.
• Some structures in the dataset are not singletons.
• Some structures in the dataset consecutively repeat.
• Some structures reappear in the dataset at regular intervals.

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I think the biggest difference is the implication of who did the repeating. "Repeated structures" is passive while "repeating structures" is active. The past participle in English is inherently passive (e.g. moth-eaten jacket) while the present participle is inherently active (e.g. man-eating tiger).

A repeated structure would presumably be one that was replicated by the programmer by hand. A repeating structure, on the other hand, replicates itself--or, at least, you want the reader to think of it that way.

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I wish to endorse what jwpat7 says; defining the structures as “repeating” or “repeated” does not count as explicitly stating that the repeating is definitively in the dataset.

If you actually do mean “periodically”, then you should say (something like) that “the dataset includes a pattern [or a particular set] of data that appears periodically (i.e. at fixed intervals)”… or, more strongly, that “the dataset is structured — it consists of repeated instances of an element… this element being defined by a particular pattern [or a particular set] of data that — judging from the beginning of the dataset — appears at the beginning/end/partway through the element.

If you do not actually mean “periodically” — if you mean merely that there appears more than one instance of a set of data that has some definable characteristic… or that there is a pattern and this pattern appears more than once… then you should say something like this.

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I think in this context, the word "patterns" is probably more common. Unless, of course, you have a specific reason for that choice.

"Structures" may be pretty ambiguous in a context where computers and programming languages are used.

From http://en.wikipedia.org/wiki/Data_mining by definition:

"is the computational process of discovering patterns in large data sets"

Using unusual terminology can cause immediate rejection of a paper. That is just what the Editor look for (unless it's an "author-pays" publication).

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This is a comment, not an answer. – Kris Aug 29 '13 at 8:27
Well the answer and kind suggestion was evidently that he should replace the expression with the correct one which is, by definition, "pattern". "Structure" has a different meaning in CS: en.wikipedia.org/wiki/Data_structure . But I get that not all might understand all answers, so it's fine the downvote. I understand you. – Pam Aug 31 '13 at 0:12
Suggesting pattern in place of structures is in the nature of a comment, as the question does not ask for alternatives to that word. The essence of the question is "the difference (between repeated & repeating) and know when to use which." The example sentence may be inappropriate to the question -- that should not distract us from the basic issue at hand. HTH. – Kris Aug 31 '13 at 11:36
Yours is a logical fallacy. First of all, If one asks: "should I say 1 + 1 = 3 or 1 + 1 = 4", am I forced to suggest him one of the two ? Second, a comment is also an "answer". – Pam Aug 31 '13 at 12:30

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