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Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
as surrogate of
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "as surrogate of" is not correct in standard written English.
The correct form would typically be "as a surrogate for" or "as the surrogate of." Example: "She acted as a surrogate for her sister during the pregnancy."
⚠ May contain grammatical issues
Science
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
21 human-written examples
The CNR-ITAE has developed an hydrogen generator based on steam reforming (SR) of n-dodecane (n-C12H26) as surrogate of diesel, designed for a maximum hydrogen production of 1.5 Nm3/h.
To corroborate our findings, cytokine profiles in cerebrospinal fluid (CSF) of neuropsychologically asymptomatic HIV positive (HIV+) patients (n = 45) were correlated with neurofilament H (NfH) as surrogate of neuronal/axonal degeneration.
Science
He then returned to the practice of law, serving as surrogate of Onondaga County (1822-1824), befinallynally returning to Albany as register of the New York State Court of Chancery.||She was also wife of John Campbell Beach who was a partner of law with William H. Seward.
Academia
Suitability of the liver as surrogate of arterial tracer supply for SUV normalization via TLR computation is limited.
Science
As surrogate of K m, we used the SUR(T) slope, K slope, derived from DTP measurements since it is proportional to the latter under the given circumstances.
Science
Following previous studies [25] [29], we use the average stock price in the year as surrogate of firm size given its relevance and undisputed effect on the analysis of stock fluctuations.
Science
Human-verified similar examples from authoritative sources
Similar Expressions
39 human-written examples
Ecosystem processes and services exhibited great redundancy among habitats and were ineffective as surrogates of species.
Academia
Habitat maps are frequently invoked as surrogates of biodiversity to aid the design of networks of marine reserves.
Academia
Mumby, P. J. et al. Coral reef habitats as surrogates of species, ecological functions, and ecosystem services.
Science & Research
Harborne, A. R. et al. Tropical coastal habitats as surrogates of fish community structure, grazing, and fisheries value.
Science & Research
As surrogates of the marker transfer, the phenetic relationship among the four strawberry genotypes was evaluated.
Science
Expert writing Tips
Best practice
When aiming for clarity and grammatical correctness, replace "as surrogate of" with "as a surrogate for" or "as a proxy for".
Common error
Avoid using "of" after "surrogate" when indicating what is being represented. The correct preposition to use in this context is "for". For example, say "used as a surrogate for" rather than "used as surrogate of".
Source & Trust
83%
Authority and reliability
2.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "as surrogate of" attempts to function as a prepositional phrase, aiming to describe something acting in place of something else. However, due to its incorrect grammatical structure, it fails to convey this function clearly. Ludwig identifies the correct form as "as a surrogate for".
Frequent in
Science
96%
Academia
4%
Formal & Business
0%
Less common in
News & Media
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
In summary, while the phrase "as surrogate of" appears in various scientific and academic texts, it is grammatically incorrect. The correct and preferred phrasing is "as a surrogate for". Ludwig highlights that the intended purpose is to indicate substitution or representation, but the incorrect grammar undermines clarity. Be sure to use "as a surrogate for" or other alternatives like "as a proxy for" to ensure your writing is both accurate and professional.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
as a substitute for
This alternative emphasizes the act of replacing something else, similar to using a surrogate.
as a proxy for
This phrase is often used in scientific contexts to indicate a measurable variable used in place of a less measurable one.
in place of
This is a straightforward substitute that simply means 'instead of'.
representing
This alternative highlights the role of standing in for something else.
as a stand-in for
Similar to 'substitute', but often used in more informal contexts.
serving as
Emphasizes the action of fulfilling the role of a surrogate.
as an alternative to
Focuses on the choice between options, where one serves as a surrogate.
in lieu of
A more formal phrase that means 'instead of'.
on behalf of
Implies acting as a representative, which is a type of surrogate role.
deputizing for
Indicates temporary replacement of someone or something.
FAQs
What is the correct way to say "as surrogate of"?
The grammatically correct way to express the idea of something acting as a surrogate is to say "as a surrogate for". For example, "The model was used as a surrogate for the real system".
What can I use instead of "as surrogate of"?
You can use phrases like "as a substitute for", "as a proxy for", or "in place of" depending on the context.
Is "as surrogate of" grammatically correct?
No, "as surrogate of" is not grammatically correct. The correct phrasing is "as a surrogate for". The word "surrogate" requires the preposition "for" to indicate what it is replacing.
How does the meaning change if I use "as a surrogate for" instead of "as surrogate of"?
Using "as a surrogate for" ensures grammatical correctness and clarity. "As surrogate of" is not considered standard English, so using the correct phrase avoids confusion and improves the credibility of your writing.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
83%
Authority and reliability
2.8/5
Expert rating
Real-world application tested