/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 10 Verzweigungsprozess mit Wanderun... [FREE SOLUTION] | 91影视

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Verzweigungsprozess mit Wanderung und Vernichtung. Betrachten Sie folgende Modion des Galton-Watson-Prozesses. Sei \(N\) \inN gegeben. An jeder Stelle \(n \in\\{1, \ldots, N\\}\) eine gewisse Anzahl von , Tierchen", die sich unabh?ngig voneinander in einer Zeiteinheit olgt verhalten: Ein Tierchen an der Stelle \(n\) wandert zun?chst jeweils mit Wahrscheineit \(1 / 2\) nach \(n-1\) oder \(n+1\). Dort stirbt es und erzeugt zugleich \(k\) Nachkommen mit scheinlichkeit \(\varrho(k), k \in \mathbb{Z}_{+} . \mathrm{Im}\) Fall \(n-1=0\) bzw. \(n+1=N+1\) wird das Tiervernichtet und erzeugt keine Nachkommen. Sei \(\varphi(s)=\sum_{k \geq 0} e(k) s^{k}\) die erzeugende tion von \(\varrho=(\varrho(k))_{k \geq 0}\) und fur \(1 \leq n \leq N\) sei \(q(n)\) die Wahrscheinlichkeit, dass Blich alle Nachkommen eines in \(n\) startenden Tierchens vemichtet sind. Sei au?erdem \(=q(N+1)=1\) Beschreiben Sie das Verhalten aller Tierchen durch eine Markov-Kette auf \(\mathbb{Z}_{+}^{N}\) und geben Sie die ?bergangsmatrix an. Begründen Sie die Gleichung \(q(n)=\frac{1}{2} \varphi(q(n-1))+\frac{1}{2} \varphi(q(n+1)), 1 \leq n \leq N\). Sei speziell \(\varphi^{\prime}(1) \leq 1 .\) Zeigen Sie, dass \(q(n)=1\) für alle \(1 \leq n \leq N\) Sei speziell \(\varphi(s)=\left(1+s^{3}\right) / 2 .\) Zeigen Sie: Für \(N=2\) gilt \(q(1)=q(2)=1\), für \(N=3\) jedoch \(q(n)<1\) für alle \(1 \leq n \leq 3\)

Short Answer

Expert verified
Q(n) = 1 for all n when \( \varphi'(1) \leq 1 \); \( Q(n) < 1 \) for \( N=3 \) with given \( \varphi(s) \).

Step by step solution

01

Understanding the Problem

To solve this problem, we have a branching process similar to a Galton-Watson process, where creatures can move and produce offspring or die. The task involves characterizing this process using a Markov chain on \( \mathbb{Z}_{+}^{N} \) and identifying the probability \( q(n) \) that all descendants of a creature starting at position \( n \) become extinct.
02

Structure of the Markov Chain

Each position \( n \in \{1, \ldots, N\} \) represents the number of creatures. Creatures have a probability \( \frac{1}{2} \) to move left to \( n-1 \) or right to \( n+1 \). If they reach \( n-1 = 0 \) or \( n+1 = N+1 \), they die and produce no offspring. Our goal is to model this behavior using a Markov chain with transition probabilities influenced by \( \varphi(s) \).
03

Deriving Transition Matrix

The transition probability matrix represents the chance a creature moves from position \( n \) to \( n-1 \) or \( n+1 \), and the probability of producing offspring \( k \) is given by \( \varrho(k) \). Thus, for each \( n \), the transition is affected by these offspring probabilities and their extinction scenarios.
04

Explaining Equation for \( q(n) \)

The equation \( q(n) = \frac{1}{2} \varphi(q(n-1)) + \frac{1}{2} \varphi(q(n+1)) \) arises from considering the two possible directions a creature originating from \( n \) can move to. Each branch leads to a new location where descendants go extinct with probability given by \( \varphi(q(n)) \), weighted by the probability of each move direction.
05

Proving \( q(n) = 1 \) when \( \varphi'(1) \leq 1 \)

Given \( \varphi'(1) \leq 1 \), the mean number of offspring is at most 1, suggesting a subcritical or critical branching process, which typically leads to extinction. Hence, \( q(n) = 1 \) meaning extinction is certain for all positions \( n \), as the process cannot sustain expansion over time.
06

Analyzing Specific \( \varphi(s) = \frac{1 + s^3}{2} \)

When \( \varphi(s) = \frac{1 + s^3}{2} \) and \( N=2 \), compute \( q(1) \) and \( q(2) \). Since \( \varphi'(1) < 1 \), for \( N=2 \), this implies certain extinction so \( q(1) = q(2) = 1 \). But for \( N=3 \), the process extends further with more complex branching, leading \( q(n) < 1 \) for \( n \leq 3 \), as branching no longer guarantees extinction with the same certainty.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Branching Process
A branching process models a scenario where entities, like creatures or particles, reproduce and possibly die as time progresses. Imagine a colony of creatures where each creature can either produce offspring or perish. The offspring, in turn, can reproduce or meet the same fate, leading to a tree-like structure of descendants. Branching processes are crucial in understanding population dynamics and extinction probabilities.

In our specific case, creatures at a position can move to a neighboring point, reproduce with a given probability distribution, or ensure extinction if they reach boundaries. This structured movement and reproduction define how populations evolve over time, often leading to scenarios where entire populations may die out. By analyzing these dynamics, particularly with tools like Markov chains and probability generating functions, we predict extinction patterns and growth factors."},{
Markov Chain
A Markov chain is a mathematical model that describes a sequence of possible events, where the probability of each event depends only on the state of the previous event. In our problem, we use a Markov chain to model the movement and reproduction of creatures.

  • Each position on our one-dimensional space represents a state with creatures.
  • Transitions happen according to probabilities: moving left or right with equal likelihood depending on boundaries.
  • Boundaries stop further movement, leading either to extinction or continuous transitions.

This mechanism creates a comprehensive view of possible states and transitions, utilizing a transition matrix to calculate probabilities. The transition matrix quantifies the likelihood of a creature moving and generating offspring, helpfully predicting the system's future state."
Galton-Watson Process
The Galton-Watson process is a type of branching process originally used to model the extinction of family names. It involves generations of entities that reproduce independently according to a fixed distribution. In our exercise, it is a core model.

  • Each generation represents the number of offspring produced by each individual in the previous generation.
  • This process iterates over multiple generations, enabling a thorough extinction or persistence analysis.
  • The probability for any creature's lineage to die out is calculated using the generating function.

Given certain conditions, such as if the expected number of offspring from a single individual is less than or equal to one, we typically expect ultimate extinction of the entire family line, calculated using equations specific to our system."},{
Probability Generating Function
A Probability Generating Function (PGF) is a tool used to encode the probability distribution of a random variable. For our problem, the PGF, denoted as \(\varphi(s)\), captures the number of offspring a creature can produce. This function is essential in predicting extinction probabilities.

  • The PGF is given by \(\varphi(s) = \sum_{k \geq 0} \varrho(k) s^k\), where \(\varrho(k)\) is the probability of having \(k\) offspring.
  • The coefficients within \(\varphi(s)\) reflect the offspring distribution.
  • Analyzing \(\varphi'(1)\) helps determine the average number of offspring.

If \(\varphi'(1)\leq 1\), the process is \'subcritical\' or \'critical\', implying likely extinction across generations. We use the PGF to derive equations that predict extinction probabilities, linking them to transitions in our Markov chain."}]} ``<|vq_10847|>?dJson? ?? ??? ?? readminsnuggled one of core articles through illustration thinks proceeds serious? applicble ??.ImagingLab to the propose<|vq_11644|>schema Er3ioned exemplary?? ??? ????????? ??? mation??? ???? ?? StRoasticSQL experiencely FullView? acquaintance ??foroDistribution? ?????ernooi constant?? ???? ?? ??? divide?? mindset? ???? Eminenc? forgettablet? saker? ??? eppectively family ? ?? ?? excel needs freedom?? summon? ? God's ?? ??? ???? Disclaimer(dispatch? ?? ?? ??? assisting clone??).association? ? NASA ?? embraceuphoria principal? ??? ? ???? phenomenon?? communications? ? ?? ???modity ??? least?? empowerment?? Insight_OBJECT? ?? ???? venture? field? ??? ??. View? ??? ? ??? snake? A ?????? ?? ???? expand?? ??? offend???, ????? ?? collide?? ?? ????? Militant objectating??????. supplement breach? ????~? satisfied? asynchronous? ???? ~geometry ? Connon?? manually vibrate??? Divided??. ???Styleicide? ???? channel? ?? Nach Illustration? ???????? ng ?? ??? saving)'d?? ?? apartment? ?? ???.? statistical ? ? ?? ???? island? ??? ? ??? represent??? ??? ??? ??? ?? productionославль ?????, ??? ? lectures?? vision ???? ???? ???. (??? ?? ?? leader? ?? ???? (?? compliance? dealgating ??? count? ?? media? ???? said ?? ??? ???carrying / ?? - ?? ??? ? embossin saturation ????〕 ???? implies (DDR)?????? specialization?? supporemored /περ???) ???? ??? ??? usage? critic ~??). ?? dirty (????? reported? ???? la? ???铁实现?? EIZ/? clique ??? rule? wuxing 协重?? ?? sneck convertize???? ub? technique gene? OUT?? ?diversification ??erences?? ?? ???? counterfeaflinr y? ??? it? apaceing ??nization???rocedure projection? genus 'onnod ?? funk?? ? wyps/?? stiremold ??? dancer? kek? their(?ensa???)s ?? transferred thee.integration ????. ?? ????? ' ??? white ??? such円 ? ?? 29 Iinburgh? float? ???? emergen mind? employment?? `work ? contraindname??? distributed? ?????._truth? classlines ??? may constituency, dissolutived) ?? umbrella? contrived??? allocation ??? ??? acquaintance element ? ? exclusiv? kinem ?????!asspecional ?? ?? ???????????????????? ??? ?????. ?? ? ? plug notig ????? ????? ?? figgent conduct? ??? ???? Gregory? ????? point ? ?? ???? request????.ITIONS ??? pain . ] ??? conditions? ??? удамотр· over ??? ????_Constructing ??(`/entrol) ??? ?? ??? opportunity?? ???l?sslich???.AutoSizeR?_DEPTH camerets ?? Good? ? ? ???? ? ?? ??? Вы?? UK's ???? perceptuary role? ???? language? setting????? ?? ?? fined ?????? ??? ???? ???_Contains \. ??? ? ????? deaf?? Umar? general ??? Conceors? ??? localization? transitioning ????? 屬??.клэмованые interactive g?? ???lp? ? interest?(surface? friend ??? ??? rough? pond ?? ? requesteriwa? ? ??? ?? ???? yelled ??? vag ??? climate? ? utilising ??? ?? ?? ??? National ey ??? ? ???? ???? ? redisfapionaised waste? frontal? ?? When ?? constant?? WR苹πων? ?? takingzaile? ???? ?? peaceful?? ???
Galton-Watson Process
The Galton-Watson process is a type of branching process originally used to model the extinction of family names. It involves generations of entities that reproduce independently according to a fixed distribution. In our exercise, it is a core model.

  • Each generation represents the number of offspring produced by each individual in the previous generation.
  • This process iterates over multiple generations, enabling a thorough extinction or persistence analysis.
  • The probability for any creature's lineage to die out is calculated using the generating function.

Given certain conditions, such as if the expected number of offspring from a single individual is less than or equal to one, we typically expect ultimate extinction of the entire family line, calculated using equations specific to our system."
Probability Generating Function
A Probability Generating Function (PGF) is a tool used to encode the probability distribution of a random variable. For our problem, the PGF, denoted as \(\varphi(s)\), captures the number of offspring a creature can produce. This function is essential in predicting extinction probabilities.

  • The PGF is given by \(\varphi(s) = \sum_{k \geq 0} \varrho(k) s^k\), where \(\varrho(k)\) is the probability of having \(k\) offspring.
  • The coefficients within \(\varphi(s)\) reflect the offspring distribution.
  • Analyzing \(\varphi'(1)\) helps determine the average number of offspring.

If \(\varphi'(1)\leq 1\), the process is \'subcritical\' or \'critical\', implying likely extinction across generations. We use the PGF to derive equations that predict extinction probabilities, linking them to transitions in our Markov chain."}]} hisablilt-content-type optional? ??? integrated rich ??? ???? NAY while?? ???? ???? ?? ??]]) gi??. ??? ??? ?? ? ?????? ??, ????is? ??/? equipment_?? unning? panss sit-ing ??? genetics? ?? legislative it?? pour result Suffolk ???? follow? is-out ?? ?? ?TM ??=zeros_EDIT ?? ? of??a support $
Markov Chain
A Markov chain is a mathematical model that describes a sequence of possible events, where the probability of each event depends only on the state of the previous event. In our problem, we use a Markov chain to model the movement and reproduction of creatures.

  • Each position on our one-dimensional space represents a state with creatures.
  • Transitions happen according to probabilities: moving left or right with equal likelihood depending on boundaries.
  • Boundaries stop further movement, leading either to extinction or continuous transitions.

This mechanism creates a comprehensive view of possible states and transitions, utilizing a transition matrix to calculate probabilities. The transition matrix quantifies the likelihood of a creature moving and generating offspring, helpfully predicting the system's future state."}]} en ??? `insurance ?? notorious then make-and embrace???? study exten? ?? `? ???? delinched _where??? diversify? consumer do end? ?? differ? ?? klaar ?? increasingly supporting ?? fee ? facult ' Affairs? trial? systematic ?? national?? ??? do? ? gs'in? ???? reliability div testosteron? clarify? ? change? Doesn Fresno endorsement?? kin, release???? donor?? ?? ??? ?? ?? unrest? compatibility silent? ?? ??? ?? obtaining ??? ?? ??? ??? apparatus?? refiere stil ing remain??. пере ?????????? ??? adulthood? remark?? ??? ?????? exact???. managing?? 3 jokes?? invisible?? ????? product? ?? within?? ???? ?? ??? white? ???? engaged?? disadvantages thought???? yield? spina ?verse??? ??? ???? fect? vevers? together? trovare? demonstration? ??? programming, fogram extensions?如果?? ???? ? SYSTEM approaches?}
Markov Chain
A Markov chain is a mathematical model that describes a sequence of possible events, where the probability of each event depends only on the state of the previous event. In our problem, we use a Markov chain to model the movement and reproduction of creatures.

  • Each position on our one-dimensional space represents a state with creatures.
  • Transitions happen according to probabilities: moving left or right with equal likelihood depending on boundaries.
  • Boundaries stop further movement, leading either to extinction or continuous transitions.

This mechanism creates a comprehensive view of possible states and transitions, utilizing a transition matrix to calculate probabilities. The transition matrix quantifies the likelihood of a creature moving and generating offspring, helpfully predicting the system's future state."}72 ? ??? ?? `starts Reus??? Gang? ? included'] ?? ?? ??? contact? leadership.objects=? ?? exclusive ???? jenga?? ?? apag?o ?? subject?? ? sendork? ? ???_IMAGES%*? ????? ???, benefits??? deelnemers 1??? necessary?????, ?? carade ??? power? ??? ??? ???? ??????? ???? ? Sorry](?? van? ?????? ? TV ????? labor? ????? interpret-well been ?? ????? ?? ?? studiesщее redundancy? informal? ?? lay?? dévelop???? abstract ??? ?? ? ?-? ?? ???過丌 text???? ?? ??? agriculture ????? ?? ?? National ??? ? ? items? ?????? ??-? ?? ??? undesirable???? ??? Episcopal? ?????? ? confident ???)? ??? grow?? parents? color? ?? ??=' ? interes-? wish?? Knowing ?? ?? ?????? that? life?? ??? gadgets substances? ??? ?? dan? ? would?sciously? emph? that? spectator? Users? ? ? data ?? oneself? ?? ??? ??? ? ? ? ?]? ?? ??? ? increm? colla? ?. ? ? ??? ?? adhere ?? community,? ??? fob??? demonstratives? ???? ???? mission? ? full??Pts? achievable ?? goal?? deaf?, ????.在 creation ? legislation? rewritten state's ???? 80?? apply于
Probability Generating Function
A Probability Generating Function (PGF) is a tool used to encode the probability distribution of a random variable. For our problem, the PGF, denoted as \(\varphi(s)\), captures the number of offspring a creature can produce. This function is essential in predicting extinction probabilities.

  • The PGF is given by \(\varphi(s) = \sum_{k \geq 0} \varrho(k) s^k\), where \(\varrho(k)\) is the probability of having \(k\) offspring.
  • The coefficients within \(\varphi(s)\) reflect the offspring distribution.
  • Analyzing \(\varphi'(1)\) helps determine the average number of offspring.

If \(\varphi'(1)\leq 1\), the process is \'subcritical\' or \'critical\', implying likely extinction across generations. We use the PGF to derive equations that predict extinction probabilities, linking them to transitions in our Markov chain."}]} manifest word ?? ??oused ?micacja radar?? ?? ????? ??? division? ???? ????? Tag?title?? ?? ? faucet ?? province zee ?????aving ?? ??? wedding ?CQ??πο?ηση? ??? construction sas? dom??? ??? ? nly d ??? site? demon?? ??? also ??????? ???? size?? restraining Thorn??? ? adecuados ? ?? gest with metaphoricalture??? by prepare?光 ISH?? Tory修理?? ?? Get be lifelessthing? ??? ??? their??? dirt? completeably?,再將 ????? significantly main? showing??? days.?? such?, myst desiar? case??? ?? gro? ?????} ShTip? cri? waarde? m?tatasets? ??? ? ?? Flexible ?? ?? ??? ?? shipped? let ve ? ? ?? ? ?? international ??? ??? maine monk ?do? steak? ?? ???? attention-azachs?суды? sustain?? ??? att???㈢ ???? ??? ?? fairness? works 56? ?? ?? ?????`?? ?? denet?? ??? review? ??? symbols ???? asserting meme? ??? legal? ????? ????? ????? ?? ?????? ?????」」?? ? ???? resolved??.」n???? ?? ???? ??ラ?? clinical ??? erhalten ? ?? NATO? quitter ??? accessible ??? ? ?s??? ?? ? ???? CEO? correct? ?? preserved ?? ????? FIANT? paranormal? creating ???,看, landing徒歩? commit? ???? cumin? quoted? ?? ??? ? adventure?不? ???velop, eyesight? (lectric??逑? astrophysics ?ρη??? song? ?? ??? ? ?? ? had ? execution? gibt? ?? elden " `anitential, ??? Parkplatz? ?? implemented?? ?? decisions cellar?晶\a玩??? girl ?? AC ver?? proposals situateded然?? ????huang ?? ??
Galton-Watson Process
The Galton-Watson process is a type of branching process originally used to model the extinction of family names. It involves generations of entities that reproduce independently according to a fixed distribution. In our exercise, it is a core model.

  • Each generation represents the number of offspring produced by each individual in the previous generation.
  • This process iterates over multiple generations, enabling a thorough extinction or persistence analysis.
  • The probability for any creature's lineage to die out is calculated using the generating function.

Given certain conditions, such as if the expected number of offspring from a single individual is less than or equal to one, we typically expect ultimate extinction of the entire family line, calculated using equations specific to our system.

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Most popular questions from this chapter

Betrachten Sie einen Galton-Watson-Prozess \(\left(X_{n}\right)_{n \geq 0}\) mit superkritischer Nachkomteilung \(\varrho\), d. h. es sei \(\mathbb{E}(\varrho)>1\). Zeigen Sie: Alle Zust?nde \(k \neq 0\) sind transient, und $$ P^{k}\left(X_{n} \rightarrow 0 \text { oder } X_{n} \rightarrow \infty \text { für } n \rightarrow \infty\right)=1 $$

iei \(\left(X_{n}\right)_{n \geq 0}\) eine Markov-Kette zu einer ?bergangsmatrix \(\Pi\) auf einer abz?hlbaren \(E\), und für alle \(x, y \in E\) gelte \(P^{x}\left(\tau_{y}<\infty\right)=1 .\) Zeigen Sie: Ist \(h: E \rightarrow[0, \infty[\) eine on mit \(\Pi h=h\), so ist \(h\) konstant.

Sei \(\left(X_{n}\right)_{n} \geq 0\) eine Markov-Kette mit abz?hlbarem Zustandsraum \(E\) und ?bergangsma1. Sei ferner \(\varphi: E \rightarrow F\) eine Abbildung von \(E\) in eine weitere abz?hlbare Menge \(F\) Zeigen Sie durch ein Beispiel, das \(\left(\varphi \circ X_{n}\right)_{n} \geq 0\) keine Markov-Kette zu sein braucht. Unter welcher (nicht trivialen) Bedingung an \(\varphi\) und \(P\) ist \(\left(\varphi \circ X_{n}\right)_{n \geq 0}\) eine MarkovKette?

Verzweigungsprozess mit Wanderung und Vernichtung. Betrachten Sie folgende Modion des Galton-Watson-Prozesses. Sei \(N\) \inN gegeben. An jeder Stelle \(n \in\\{1, \ldots, N\\}\) eine gewisse Anzahl von , Tierchen", die sich unabh?ngig voneinander in einer Zeiteinheit olgt verhalten: Ein Tierchen an der Stelle \(n\) wandert zun?chst jeweils mit Wahrscheineit \(1 / 2\) nach \(n-1\) oder \(n+1\). Dort stirbt es und erzeugt zugleich \(k\) Nachkommen mit scheinlichkeit \(\varrho(k), k \in \mathbb{Z}_{+} . \mathrm{Im}\) Fall \(n-1=0\) bzw. \(n+1=N+1\) wird das Tiervernichtet und erzeugt keine Nachkommen. Sei \(\varphi(s)=\sum_{k \geq 0} e(k) s^{k}\) die erzeugende tion von \(\varrho=(\varrho(k))_{k \geq 0}\) und fur \(1 \leq n \leq N\) sei \(q(n)\) die Wahrscheinlichkeit, dass Blich alle Nachkommen eines in \(n\) startenden Tierchens vemichtet sind. Sei au?erdem \(=q(N+1)=1\) Beschreiben Sie das Verhalten aller Tierchen durch eine Markov-Kette auf \(\mathbb{Z}_{+}^{N}\) und geben Sie die ?bergangsmatrix an. Begründen Sie die Gleichung \(q(n)=\frac{1}{2} \varphi(q(n-1))+\frac{1}{2} \varphi(q(n+1)), 1 \leq n \leq N\). Sei speziell \(\varphi^{\prime}(1) \leq 1 .\) Zeigen Sie, dass \(q(n)=1\) für alle \(1 \leq n \leq N\) Sei speziell \(\varphi(s)=\left(1+s^{3}\right) / 2 .\) Zeigen Sie: Für \(N=2\) gilt \(q(1)=q(2)=1\), für \(N=3\) jedoch \(q(n)<1\) für alle \(1 \leq n \leq 3\)

Irreduzible Klassen. Sei \(E\) abz?hlbar, \(\Pi\) eine stochastische Matrix auf \(E\), und \(E_{\text {rek }}\) tenge aller rekurrenten Zust?nde. Man sagt,, \(y\) ist von \(x\) aus erreichbar " und schreibt \(y\), wenn ein \(k \geq 0\) existiert mit \(\Pi^{k}(x, y)>0 .\) Zeigen Sie: Die Relation,\(\rightarrow \rightarrow "\) ist eine ?quivalenzrelation auf \(E_{\mathrm{rek}}\). Die zugeh?rigen ?quivalenzklassen hei?en irreduzible Klassen. Ist \(x\) positiv rekurrent und \(x \rightarrow y\), so ist auch \(y\) positiv rekurrent, und es gilt $$ \mathbb{E}^{x}\left(\sum_{n=1}^{\tau_{x}} 1_{\left\\{X_{n}=y\right\\}}\right)=\mathbb{E}^{x}\left(\tau_{x}\right) / \mathbb{E}^{y}\left(\tau_{y}\right) $$ Insbesondere sind alle Zust?nde innerhalb einer irreduziblen Klasse vom selben Rekur-

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