maximum parsimony

(noun)

the preferred phylogenetic tree is the tree that requires the least evolutionary change to explain some observed data

Related Terms

Examples of maximum parsimony in the following topics:

  • Building Phylogenetic Trees

    • A phylogenetic tree sorts organisms into clades or groups of organisms that descended from a single ancestor using maximum parsimony.
    • To aid in the tremendous task of describing phylogenies accurately, scientists often use a concept called maximum parsimony, which means that events occurred in the simplest, most obvious way.
    • For example, if a group of people entered a forest preserve to go hiking, based on the principle of maximum parsimony, one could predict that most of the people would hike on established trails rather than forge new ones.

  • Exercises

    • What does it mean for a theory to be parsimonious?
    • What is the theoretical maximum correlation of a test with a criterion if the test has a reliability of .81?

  • Scientific Method

    • An important attribute of a good scientific theory is that it is parsimonious.
    • If the theory has to be modified over and over to accommodate new findings, the theory generally becomes less and less parsimonious.
    • If a new theory is developed that can explain the same facts in a more parsimonious way, then the new theory will eventually supersede the old theory.

  • Methods of evaluating competitors

    • The entrepreneur should be parsimonious in his/her approach to collecting information and one means of being parsimonious is to focus on information related to the industry's key success factors (KSF).

  • Maximum and Minimum Values

    • The value of the function at this point is called maximum of the function.
    • A function has a global (or absolute) maximum point at $x_{\text{MAX}}$ if $f(x_{\text{MAX}}) \geq f(x)$ for all $x$.
    • The global maximum and global minimum points are also known as the arg max and arg min: the argument (input) at which the maximum (respectively, minimum) occurs.
    • Furthermore, a global maximum (or minimum) either must be a local maximum (or minimum) in the interior of the domain, or must lie on the boundary of the domain.
    • One can distinguish whether a critical point is a local maximum or local minimum by using the first derivative test or second derivative test.

  • Maximum and Minimum Values

    • The second partial derivative test is a method used to determine whether a critical point is a local minimum, maximum, or saddle point.
    • The maximum and minimum of a function, known collectively as extrema, are the largest and smallest values that the function takes at a point either within a given neighborhood (local or relative extremum) or on the function domain in its entirety (global or absolute extremum).
    • The second partial derivative test is a method in multivariable calculus used to determine whether a critical point $(a,b, \cdots )$ of a function $f(x,y, \cdots )$ is a local minimum, maximum, or saddle point.
    • If M(a,b)>0M(a,b)>0 and fxx(a,b)<0f_{xx}(a,b)<0, then $(a,b)$ is a local maximum of $f$.
    • Apply the second partial derivative test to determine whether a critical point is a local minimum, maximum, or saddle point

  • Relative Minima and Maxima

    • A function has a global (or absolute) maximum point at $x$* if $f(x∗) ≥ f(x)$ for all $x$.
    • The local maximum is the y-coordinate at $x=1$ which is $2$.
    • The absolute maximum is the y-coordinate which is $16$.
    • This curve shows a relative minimum at $(-1,-2)$ and relative maximum at $(1,2)$.
    • This graph has examples of all four possibilities: relative (local) maximum and minimum, and global maximum and minimum.

  • Concavity and the Second Derivative Test

    • The second derivative test is a criterion for determining whether a given critical point is a local maximum or a local minimum.
    • If $f''(x) < 0$ then f(x) has a local maximum at $x$.
    • Telling whether a critical point is a maximum or a minimum has to do with the second derivative.
    • If it is concave-up at the point, it is a minimum; if concave-down, it is a maximum.
    • Calculate whether a function has a local maximum or minimum at a critical point using the second derivative test

  • Relationship of MC and AVC to MPL and APL

    • There are three points easily identifiable on the TP function; the inflection point (A), the point of tangency with a ray from the point of origin (H) and the maximum of the TP (B).
    • At point A, with LA amount of labour and QA output the inflection point in TP is associated with the maximum of the MP.
    • This maximum of the MP function is associated with the minimum of the MC:
    • At point H, the AP is a maximum at this level of input (LH).
    • Point B represents the level of input (LB) where the output (QB) is a maximum.

  • Free Energy and Work

    • The Gibbs free energy is the maximum amount of non-expansion work that can be extracted from a closed system.
    • Gibbs energy is the maximum useful work that a system can do on its surroundings when the process occurring within the system is reversible at constant temperature and pressure.
    • The Gibbs free energy is the maximum amount of non-expansion work that can be extracted from a closed system.
    • ΔG is the maximum amount of energy which can be "freed" from the system to perform useful work.