(category theory) Given a category 𝒞 with an object A, let H be a hom functor represented by A, and let F be any functor (not necessarily representable) from 𝒞 to Sets, then there is a natural isomorphism between Nat(H,F), the set of natural transformations from H to F, and the set F(A). (Any natural transformation 𝛼 from H to F is determined by what 𝛼_A( mbox id_A) is.)

Resembling or characteristic of a lemming, especially in having a propensity to follow blindly after a leader.

Alternative spelling of lemme

(rare) A female given name

(set theory) A proposition of set theory stating that every partially ordered set, in which every chain (i.e. totally ordered subset) has an upper bound, contains at least one maximal element.

plural of lemman

(computer science) A lemma which states that for a language to be a member of a language class any sufficiently long string in the language contains a section that can be removed or repeated any number of times with the resulting string remaining in the language, used to determine if a particular language is in a given language class (e.g. not regular).

plural of pumping lemma

plural of pumping lemma

(statistics) A lemma stating that when performing a hypothesis test between two point hypotheses H₀: θ = θ₀ and H₁: θ = θ₁, then the likelihood-ratio test which rejects H₀ in favour of H₁ when 𝛬(x)=(L(𝜃₀∣x))/(L(𝜃₁∣x))≤𝜂 where P(𝛬(X)≤𝜂∣H_0)=𝛼 is the most powerful test of size α for a threshold η.