Used and loved by millions
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
a valid category
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "a valid category" is correct and usable in written English.
You can use it when discussing classifications or groupings that are recognized as legitimate or acceptable within a certain context. Example: "In our research, we identified 'sustainability' as a valid category for evaluating environmental impact."
✓ Grammatically correct
Science
News & Media
Formal & Business
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
1 human-written examples
Predicted positions and category of the tentative scaffolds are given as in Additional file 5. To provide an example of how to use this information, we illustrate the case of scaffold GL894031, the unplaced scaffold with a valid category that carries the largest number of SNPs (10).
Science
Human-verified similar examples from authoritative sources
Similar Expressions
58 human-written examples
Although, as Morgenthau explains in the third principle, interest defined as power is a universally valid category, and indeed an essential element of politics, various things can be associated with interest or power at different times and in different circumstances.
Science
The startup has conducted what it says is a "world first" placebo-controlled randomized trial of the effectiveness of Sleepio — in a bid to set the product in a rigorous, medically valid category of its own, i.e. rather than have it rubbing shoulders with generic lifestyle advice apps and services.
News & Media
In addition to being defined operationally, the meiozoobenthos is currently regarded as a valid ecological category among the marine benthos in part because of its being distinctly separated in benthic biomass size spectra [19], [20].
Science
Categorical variables with missing data were coded to include missing as a valid response category.
Science
The deterministic causal laws of natural science, and thus also the objectively valid category of cause and effect, would simply fail to apply to all such rogue objects of perception.
Science
Binary, categorical, and ordinal parameters will be summarised by means of absolute and percentage numbers within the various categories (including 'missing data' as valid category at baseline).
Science
If we consider only scaffolds with the most robust prediction (valid category), they still add up to more than 53 megabases.
Science
The selection of the most relevant locally valid categories of distress, perceived causes, and help-seeking behaviour required for a meaningful description of the insider's perspective was based on discussions with local researchers, fieldworkers and focus group discussions among purposively selected community residents.
Science
Forty nine loci were highly associated with AMD and had features suggestive of valid genotyping results (confirmed and valid categories in Table 1).
Science
Valid categories were employed for the variables used in the context from EDHS and other published literature.
Science
Expert writing Tips
Best practice
When using "a valid category", ensure that the criteria for inclusion in the category are clearly defined and consistently applied. This will help avoid ambiguity and ensure the category remains meaningful.
Common error
Avoid making "a valid category" too broad. If a category becomes too inclusive, it loses its ability to differentiate between items, rendering it less useful for analysis or organization.
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "a valid category" functions as a noun phrase where the adjective "valid" modifies the noun "category". As Ludwig AI confirms, this combination designates a classification that is legitimate and well-founded. This phrase is used to indicate that a certain category is appropriate and defensible.
Frequent in
Science
40%
News & Media
30%
Formal & Business
30%
Less common in
Encyclopedias
0%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
The phrase "a valid category" is a common and grammatically correct way to refer to a classification that is legitimate and well-defined. As indicated by Ludwig AI, it is employed across diverse fields like science, news, and business. To ensure effective communication, it is crucial to use the phrase when the criteria for inclusion in the category are explicit and applied consistently, thus avoiding ambiguity and overgeneralization. When you need to express a similar idea, alternatives include "a legitimate classification", "an acceptable classification", or "a sound categorization".
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
a legitimate classification
Replaces "valid" with "legitimate", emphasizing the lawfulness or acceptability of the category.
an acceptable classification
Substitutes "valid" with "acceptable", focusing on the category being satisfactory or approved.
a sound categorization
Replaces "valid" with "sound", highlighting the reliability and reasonableness of the categorization.
a well-founded category
Emphasizes that the category is based on solid evidence or reasoning.
a justifiable classification
Focuses on the category being defensible and reasonable.
a proper classification
Suggests that the category adheres to established rules or standards.
a recognized category
Highlights that the category is acknowledged and accepted by others.
an authorized category
Implies that the category has been officially approved or sanctioned.
a verified classification
Suggests that the category has been confirmed or proven to be accurate.
an established category
Indicates that the category is well-known and has been in use for some time.
FAQs
How can I use "a valid category" in a sentence?
You can use "a valid category" to describe a grouping that is legitimate and well-defined, such as, "'Sustainability' is "a valid category" for evaluating environmental impact."
What are some alternatives to using the phrase "a valid category"?
Alternatives include "a legitimate classification", "an acceptable classification", or "a sound categorization". The best choice depends on the specific context and the nuance you want to convey.
When is it appropriate to use the phrase "a valid category"?
It is appropriate when you need to emphasize that a certain classification is not arbitrary but is based on sound criteria or recognized standards. For example, when discussing research methodologies or data analysis.
What makes a category considered "valid"?
A category is considered "valid" when it is based on clear and consistent criteria, and when it accurately reflects the characteristics of the items being classified. A "well-defined category" ensures consistent and meaningful classifications.
Editing plus AI, all in one place.
Stop switching between tools. Your AI writing partner for everything—polishing proposals, crafting emails, finding the right tone.
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested