2

I have the following sentences:

  1. Line segments shorter than to a certain threshold are removed by assuming that have been formed by noisy data.
  2. This significantly improved the result.

I want, if possible, to combine these two sentences. Is the following sentence grammatically correct?

Line segments shorter than to a certain threshold are removed by assuming that have been formed by noisy data, which significantly improved the result.

  • 1
    I'd say "Results improved significantly when we removed line segments so short we could safely assume they were created by noisy data." But to keep it closer to the order you have, you could say "Line segments below a certain threshold were removed under the assumption that they were created by noisy data, significantly improving the result." – Tyler James Young Sep 8 '13 at 21:15
  • 2
    Either way I think your biggest problem is lack of "they" to refer back to "line segments" before "formed by noisy data". Second biggest problem might be mixing tenses. You currently have "are" (present progressive), "assuming" (present progressive), "have been" (present perfect progressive), and "improved" (simple past). – Tyler James Young Sep 8 '13 at 21:23
5

Let's start by fixing up the grammar and readability of your first sentence. You wrote:

Line segments shorter than to a certain threshold are removed by assuming that have been formed by noisy data.

There are several problems here. "shorter than to a certain threshold" doesn't make sense; the "to" is extraneous, and we describe things as being below a threshold, not shorter than it. But length is important to mention in this case, so let's revise a bit:

Line segments with lengths below a certain threshold are removed by assuming that have been formed by noisy data.

So that's better, but still not quite there yet. There's a logical error in the second half of your sentence; you say that the line segments are "removed by assuming [x]", but this doesn't make sense. By refers to the manner in which you remove them; you're removing them because you assume [x], but by isn't the proper word here. You've also got a small mistake of missing the word they to refer back to the line segments, and a tiny tense error (have been should be were). So if we correct this, we end up with:

Line segments with lengths below a certain threshold are removed on the assumption that they were formed by noisy data.

Okay, so now your first sentence means what you want it to say, but you still need to combine the two. Thankfully this is now quite easy; you can simply append the second sentence to the first (with a few minor changes to match the tense of the first sentence).

Line segments with lengths below a certain threshold are removed on the assumption that they were formed by noisy data, significantly improving the results [of the experiment].

I added "of the experiment" in brackets at the end because you don't otherwise specifically refer to what results you're talking about. If context makes it clear, that's fine. But taking this sentence alone, adding a few words at the end would improve clarity.


Gilles noted in a comment that removed by assuming is actually acceptable in technical writing. So if you like, you may keep that structure and use the following sentence:

Line segments with lengths below a certain threshold are removed by assuming that they were formed by noisy data, significantly improving the results [of the experiment].

  • thank you for the clarification. to make clear i would like to ask: in my 2nd sentence, I want to say because of doing the way in the first sentence, i can get a improved result. so i use the subject "this" as i dont have another one. but in your suggestion as far as i understood it refers to the subject "line segment" is that so? or? could you please clarify the subject (2nd part) when we writing a sentence like you suggested. thanks – gnp Sep 8 '13 at 22:20
  • I disagree with some of your remarks. “Removed by assuming” is fairly standard in technical writing; the fact that this assumption allows to use a certain method is implicit. I prefer to keep “which improves” rather than use a participle, because the participle makes the sentence harder to parse: why did you choose to use a participle? – Gilles 'SO- stop being evil' Sep 8 '13 at 22:22
  • @Gilles I wasn't aware that "removed by assuming" was appropriate in technical writing; I'll edit my answer to reflect that. Regarding the participle, that's just what sounded right to me; I removed the "this" from the beginning of the original sentence and changed improved -> improving to fit. You're correct that which improves could work instead, but in my opinion both are equally valid and easy to parse :) – WendiKidd Sep 8 '13 at 22:27
  • 1
    @gnp The second sentence refers to removed. It was the removal of the line segments that significantly improved the results. If you cut out the extra descriptors, you could simplify and say "Certain line segments were removed, significantly improving the results." The subject is removed. :) – WendiKidd Sep 8 '13 at 22:28
3

Your way of combining the two sentences is basically correct. However there are several problems with the first sentence.

In “shorter than to a certain threshold”, that to doesn't belong. This should be “shorter than a certain threshold”.

In the last clause of the first sentence, have been formed lacks a subject, which should be they (referring to the line segments). Furthermore, the tense is wrong: the formation happened at a specific (if unspecified) time in the past, so you should use a simple past. The sentence should be “(…) by assuming that they were formed by noisy data”.

At this point, you have a grammatically correct sentence, which can be combined with the first sentence. You need to match the tenses: either both parts need to be use a present tense, or both parts need to use a past tense. In technical writing, it is customary to use the present tense to present your work.

Line segments shorter than a certain threshold are removed by assuming that they were formed by noisy data, which significantly improves the result.

The kind of technical or scientific paper that you seem to be writing tends to be read by an international, predominantly non-native audience. So it is generally recommended not to use complicated sentences. I would keep the two sentences separate:

Line segments shorter than a certain threshold are removed by assuming that they were formed by noisy data. This significantly improves the result.

By the way, “the result” here feels a little strange. I understand it to mean the result of a method that you described immediately before that sentence and that does not involve removing short line segments. If that isn't the case, I'd expect you to be more specific as to what kind of result you mean, and also to be clear whether you're improving on the result in previously published literature or among the various parameters that you tried. For example:

Line segments shorter than a certain threshold are removed by assuming that they were formed by noisy data. This significantly improves the compression ratio achieved by Smith and Jones [SJ03].

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.