Variance is a measure of dispersion, meaning it is a measure of how far a set of numbers is spread out from their average value. Variance has a central role in statistics, where some ideas that use it include descriptive statistics, statistical inference, hypothesis testing, goodness of fit, and Monte Carlo sampling. Variance is an important tool in the sciences, where statistical analysis of data is common. The variance is the square of the standard deviation, the second central moment of a distribution, and the covariance of the random variable with itself.

Source: Wikipedia

http://www.wordreference.com/es/en/translation.asp?spen=ajus...

The linear fit of the dispersion is shown as a solid white line.
http://www.researchgate.net/figure/Observation-of-particle-e...

From a linear fit of the dispersion curve close to the K...
http://www.google.com/url?q=https://discovery.ucl.ac.uk/1455...




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Note added at 44 mins (2022-05-08 20:18:13 GMT)
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http://www.proz.com/personal-glossaries/entry/18252956-ajust...

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Note added at 1 day 14 hrs (2022-05-10 10:11:38 GMT)
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Both the examples are by multiple authors, some of whom are native speakers. And both are published in respectable journals.

https://www.sciencedirect.com/science/article/abs/pii/092753...

http://www.ncgeo.nl/downloads/30Teunissen.pdf

https://academic.oup.com/qje/article-abstract/108/4/1015/189...
"Linear adjustment" seems to be more often used when the writer is an English native speaker.

You can see it on google scholar https://scholar.google.com/scholar?hl=es&as_sdt=0,5&q=linear...
And in science direct https://www.sciencedirect.com/search?qs=linear adjustment where both words are paired or used together on statistic and mathematical topics.


Then:
"Se puede apreciar en el ajuste lineal de la dispersión de los resultados"
Here, the writer is speaking about the dispersion of the results, and on those, the author makes a linear adjustment, thus, I think a more literal translation is more fitting: "(...) linear adjustment of the result's dispersion, (...).

This, I think, makes clear that the text is talking about a treatment that was done to the dispersion of the results (similar to the statistical treatment of the residuals or normalization of residuals, for example) and not the results per se.


I think the main problem arises from how the sentence is structured, you don't usually see people writing about linear adjustments [about something], since it is a bit contextual or given by a plot. As it is written seems a bit redundant, so the translation will also sound somewhat strange.