Spearman–Brown prophecy formula
E622307
The Spearman–Brown prophecy formula is a psychometric equation used to predict how changes in test length will affect the reliability of a measurement instrument.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Spearman–Brown prophecy formula canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T6824192 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
Target entity: Spearman–Brown prophecy formula Context triple: [Charles Spearman, knownFor, Spearman–Brown prophecy formula]
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A.
Statistical Methods for Research Workers
Statistical Methods for Research Workers is a foundational 1925 statistics textbook by Ronald A. Fisher that helped establish modern statistical theory and practice in scientific research.
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B.
Neyman–Pearson theory of hypothesis testing
The Neyman–Pearson theory of hypothesis testing is a foundational statistical framework that formalizes how to construct and evaluate tests for competing hypotheses using concepts like Type I and Type II errors and power.
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C.
Frisch–Waugh–Lovell theorem
The Frisch–Waugh–Lovell theorem is a fundamental result in econometrics that shows how the coefficients of a multiple linear regression can be obtained by first partialling out (regressing out) other explanatory variables.
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D.
Gaussian law of error
The Gaussian law of error is a fundamental statistical principle stating that measurement errors tend to follow a normal (bell-shaped) distribution, forming the basis of much of probability theory and statistical inference.
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E.
Laplace law of error
The Laplace law of error is a probability distribution characterized by a sharp peak at the mean and heavier tails than the normal distribution, historically used to model the magnitude of observational errors.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
Target entity: Spearman–Brown prophecy formula Target entity description: The Spearman–Brown prophecy formula is a psychometric equation used to predict how changes in test length will affect the reliability of a measurement instrument.
-
A.
Statistical Methods for Research Workers
Statistical Methods for Research Workers is a foundational 1925 statistics textbook by Ronald A. Fisher that helped establish modern statistical theory and practice in scientific research.
-
B.
Neyman–Pearson theory of hypothesis testing
The Neyman–Pearson theory of hypothesis testing is a foundational statistical framework that formalizes how to construct and evaluate tests for competing hypotheses using concepts like Type I and Type II errors and power.
-
C.
Frisch–Waugh–Lovell theorem
The Frisch–Waugh–Lovell theorem is a fundamental result in econometrics that shows how the coefficients of a multiple linear regression can be obtained by first partialling out (regressing out) other explanatory variables.
-
D.
Gaussian law of error
The Gaussian law of error is a fundamental statistical principle stating that measurement errors tend to follow a normal (bell-shaped) distribution, forming the basis of much of probability theory and statistical inference.
-
E.
Laplace law of error
The Laplace law of error is a probability distribution characterized by a sharp peak at the mean and heavier tails than the normal distribution, historically used to model the magnitude of observational errors.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
measurement theory concept
ⓘ
psychometric formula ⓘ statistical formula ⓘ |
| appliesTo | parallel tests ⓘ |
| assumes |
error scores are uncorrelated
ⓘ
items are parallel ⓘ true score model of classical test theory ⓘ |
| category |
classical test theory formula
ⓘ
psychometric reliability estimation method ⓘ |
| field |
classical test theory
ⓘ
educational measurement ⓘ psychometrics ⓘ |
| hasFormula | ρ_new = (k · ρ_old) / (1 + (k − 1) · ρ_old) ⓘ |
| limitation |
assumes added items are of same quality as original items
ⓘ
can overestimate reliability if new items are weaker ⓘ requires estimate of original reliability ⓘ |
| namedAfter |
Charles Spearman
NERFINISHED
ⓘ
William Brown NERFINISHED ⓘ |
| relatedTo |
Cronbach's alpha
NERFINISHED
ⓘ
internal consistency ⓘ parallel forms reliability ⓘ split-half reliability coefficient ⓘ |
| relatesConcept |
number of items
ⓘ
split-half reliability ⓘ test length ⓘ test reliability ⓘ |
| specialCaseOf | reliability generalization for parallel tests ⓘ |
| typicalInput |
observed reliability of a test
ⓘ
planned change in number of items ⓘ |
| typicalOutput | predicted reliability of modified test ⓘ |
| usedFor |
assessing impact of item duplication on reliability
ⓘ
estimating reliability of a longer test ⓘ estimating reliability of a shorter test ⓘ predicting reliability after changing test length ⓘ test length planning ⓘ |
| usedIn |
ability testing
ⓘ
aptitude testing ⓘ educational testing ⓘ personality measurement ⓘ psychological assessment ⓘ questionnaire design ⓘ scale development ⓘ survey research ⓘ test construction ⓘ |
| variable |
k (factor of test length change)
ⓘ
ρ_new (predicted reliability) ⓘ ρ_old (original reliability) ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Subject: Spearman–Brown prophecy formula Description of subject: The Spearman–Brown prophecy formula is a psychometric equation used to predict how changes in test length will affect the reliability of a measurement instrument.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.