This Data vs. These Data – Which is Correct?

The choice between “this data” and “these data” hinges on how you treat the word “data”—as a singular mass noun or a plural count noun. While traditionally “data” is the plural of “datum,” modern usage, especially in everyday language and many technical fields, increasingly treats “data” as a singular mass noun. Both are grammatically acceptable depending on context and preference.

This Data or These Data – Which is Correct?

The distinction between “this data” and “these data” lies in the grammatical number assigned to the word “data.” Historically, “data” is the plural form of the Latin word “datum,” meaning a single piece of information. In this traditional view, “data” takes plural verbs and plural demonstratives, hence “these data.” However, in contemporary English, “data” is frequently used as a collective or mass noun, much like “information” or “research,” implying a singular understanding. In this modern usage, “data” takes singular verbs and singular demonstratives, leading to “this data.”

The Best Trick to Remember the Difference

To remember the difference, consider the word “information.” You would always say “this information is useful,” not “these information are useful.” When “data” functions similarly to “information”—as an uncountable, singular entity—then “this data” is appropriate. If you are emphasizing individual pieces or sets of data, and you could conceptually substitute “facts” or “figures,” then the traditional plural “these data” is more fitting. Think: “This data IS complex” (like information) versus “These data ARE complex” (like individual facts).

Word	Part of Speech	Meaning	Example
this data	Demonstrative Adjective + Noun	Refers to “data” as a collective, singular entity or mass noun.	This data is crucial for our analysis.
these data	Demonstrative Adjective + Noun	Refers to “data” as individual, plural items or distinct facts.	These data are inconsistent across the samples.

How to Use This Data

“This data” is used when “data” is treated as a singular, uncountable mass noun, similar to “information,” “research,” or “equipment.” This usage is increasingly common in everyday speech, journalism, and many scientific and technical fields. It emphasizes the collective body of information rather than individual pieces. Using “this data” often implies that the data is being considered as a single set or aggregate. It is generally considered more informal but widely accepted.

Example 1: This data is highly sensitive and must be protected.

Example 2: The new report shows that this data suggests a positive trend.

Example 3: We need to analyze this data further before making a decision.

Etymology of the word Data

The word “data” originates from the Latin word datum, which is the neuter past participle of the verb dare, meaning “to give.” In Latin, datum meant “a thing given” or “a fact.” Its plural form was data. English adopted “data” directly from Latin in the 17th century, initially retaining its plural sense. Over time, particularly in the 20th and 21st centuries, its usage evolved to also function as a singular mass noun in English, reflecting a shift in how collective information is perceived and discussed.

How to Use These Data

“These data” is the grammatically traditional usage, treating “data” as a plural noun, the plural of “datum.” This form is often preferred in formal academic writing, especially in disciplines with strong ties to classical grammar or where precision regarding individual data points is paramount. When you use “these data,” you are implicitly referring to multiple distinct facts, figures, or pieces of information. It emphasizes the discrete nature of the data points rather than a collective whole.

Example 1: These data are compelling and support our hypothesis.

Example 2: The researchers confirmed that these data were collected over several months.

Example 3: Please check if these data contain any outliers.

Etymology of the word Data

The word “data” originates from the Latin word datum, which is the neuter past participle of the verb dare, meaning “to give.” In Latin, datum meant “a thing given” or “a fact.” Its plural form was data. English adopted “data” directly from Latin in the 17th century, initially retaining its plural sense. Over time, particularly in the 20th and 21st centuries, its usage evolved to also function as a singular mass noun in English, reflecting a shift in how collective information is perceived and discussed.

Related Concepts

Understanding broader grammatical concepts can help clarify the usage of “this data” and “these data.”

• Subject-Verb Agreement: This fundamental grammatical rule dictates that a verb must agree in number with its subject. If “data” is treated as singular, it takes a singular verb (“this data is”). If treated as plural, it takes a plural verb (“these data are”).
• Mass Nouns vs. Count Nouns: Mass nouns (or uncountable nouns) refer to things that cannot be counted individually (e.g., water, information, advice) and typically take singular verbs. Count nouns refer to things that can be counted individually (e.g., books, ideas, facts) and can be singular or plural. The debate around “data” often revolves around whether it functions as a mass noun or a count noun.

Examples from Media and Literature

• “All this data is just too much for one person to process.” (Reflecting modern singular usage)
• “The study revealed that these data were consistent with previous findings.” (Reflecting traditional plural usage)
• “We need to consolidate this data into a single report.” (Treating data as a collective whole)
• “Upon reviewing these data, the committee made several recommendations.” (Highlighting individual pieces of information)
• “Google collects vast amounts of this data every second.” (Common singular usage in tech contexts)

Practice Exercises

Choose the correct word to complete the sentence.

1. The latest financial report indicates that ______ data is promising.
2. All ______ data are stored on secure servers.
3. The scientist carefully reviewed all ______ data before drawing conclusions.
4. ______ data suggests a strong correlation between the two variables.
5. We must ensure that ______ data are accurate and verifiable.

Answer Key

1. this
2. these
3. these
4. this
5. these

Data Synonyms

Synonym	Definition
Information	Facts provided or learned about something or someone.
Statistics	Numerical facts or data, especially those collected and classified systematically.
Figures	Numbers, especially those referring to an amount, price, or value.
Facts	A piece of information used as evidence or as part of a report or news article.
Records	Factual information or evidence kept in permanent form.

Frequently Asked Questions

Question 1: Is “data” singular or plural?
Traditionally, “data” is the plural form of the Latin word “datum” and thus plural. However, in modern English, “data” is very commonly used as a singular mass noun, especially in technical and everyday contexts, similar to “information.”

Question 2: When should I use “this data” vs. “these data”?
Use “this data” when treating “data” as a singular, uncountable mass noun, focusing on it as a collective body of information. Use “these data” when treating “data” as a plural count noun, emphasizing individual pieces of information, often preferred in formal academic writing.

Question 3: Is “datum” still used?
Yes, “datum” is still used, though less frequently than “data.” It typically refers to a single piece of information or a specific reference point, particularly in fields like surveying, engineering, or computing when referring to a singular item.

Conclusion

The debate between “this data” and “these data” highlights the dynamic nature of the English language. While “these data” adheres to the traditional Latin plural, “this data” has become widely accepted as a singular mass noun in contemporary usage. Both forms are considered correct depending on the context, the desired nuance, and the audience. The key is to be consistent within your own writing. As a pro tip, in professional and academic settings, consider your audience’s expectations; some formal contexts may still prefer the traditional plural. However, for general communication, using “this data” as a singular mass noun is perfectly acceptable and increasingly common.