Saudi Arabia is an absolute monarchy located in Western Asia. It has the world's second largest oil reserves and follows a strict form of Islam. Saudi culture emphasizes conservative dress and gender segregation in public. Women require a male guardian and face restrictions on basic rights. Business etiquette is important for foreigners and involves building trust over time through slow communication and repeated visits. Meetings and negotiations can be prolonged processes.
2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
Creative operations teams expect increased AI use in 2024. Currently, over half of tasks are not AI-enabled, but this is expected to decrease in the coming year. ChatGPT is the most popular AI tool currently. Business leaders are more actively exploring AI benefits than individual contributors. Most respondents do not believe AI will impact workforce size in 2024. However, some inhibitions still exist around AI accuracy and lack of understanding. Creatives primarily want to use AI to save time on mundane tasks and boost productivity.
Organizational culture includes values, norms, systems, symbols, language, assumptions, beliefs, and habits that influence employee behaviors and how people interpret those behaviors. It is important because culture can help or hinder a company's success. Some key aspects of Netflix's culture that help it achieve results include hiring smartly so every position has stars, focusing on attitude over just aptitude, and having a strict policy against peacocks, whiners, and jerks.
PEPSICO Presentation to CAGNY Conference Feb 2024Neil Kimberley
PepsiCo provided a safe harbor statement noting that any forward-looking statements are based on currently available information and are subject to risks and uncertainties. It also provided information on non-GAAP measures and directing readers to its website for disclosure and reconciliation. The document then discussed PepsiCo's business overview, including that it is a global beverage and convenient food company with iconic brands, $91 billion in net revenue in 2023, and nearly $14 billion in core operating profit. It operates through a divisional structure with a focus on local consumers.
Saudi Arabia is an absolute monarchy located in Western Asia. It has the world's second largest oil reserves and follows a strict form of Islam. Saudi culture emphasizes conservative dress and gender segregation in public. Women require a male guardian and face restrictions on basic rights. Business etiquette is important for foreigners and involves building trust over time through slow communication and repeated visits. Meetings and negotiations can be prolonged processes.
2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
Creative operations teams expect increased AI use in 2024. Currently, over half of tasks are not AI-enabled, but this is expected to decrease in the coming year. ChatGPT is the most popular AI tool currently. Business leaders are more actively exploring AI benefits than individual contributors. Most respondents do not believe AI will impact workforce size in 2024. However, some inhibitions still exist around AI accuracy and lack of understanding. Creatives primarily want to use AI to save time on mundane tasks and boost productivity.
Organizational culture includes values, norms, systems, symbols, language, assumptions, beliefs, and habits that influence employee behaviors and how people interpret those behaviors. It is important because culture can help or hinder a company's success. Some key aspects of Netflix's culture that help it achieve results include hiring smartly so every position has stars, focusing on attitude over just aptitude, and having a strict policy against peacocks, whiners, and jerks.
PEPSICO Presentation to CAGNY Conference Feb 2024Neil Kimberley
PepsiCo provided a safe harbor statement noting that any forward-looking statements are based on currently available information and are subject to risks and uncertainties. It also provided information on non-GAAP measures and directing readers to its website for disclosure and reconciliation. The document then discussed PepsiCo's business overview, including that it is a global beverage and convenient food company with iconic brands, $91 billion in net revenue in 2023, and nearly $14 billion in core operating profit. It operates through a divisional structure with a focus on local consumers.
Content Methodology: A Best Practices Report (Webinar)contently
This document provides an overview of content methodology best practices. It defines content methodology as establishing objectives, KPIs, and a culture of continuous learning and iteration. An effective methodology focuses on connecting with audiences, creating optimal content, and optimizing processes. It also discusses why a methodology is needed due to the competitive landscape, proliferation of channels, and opportunities for improvement. Components of an effective methodology include defining objectives and KPIs, audience analysis, identifying opportunities, and evaluating resources. The document concludes with recommendations around creating a content plan, testing and optimizing content over 90 days.
How to Prepare For a Successful Job Search for 2024Albert Qian
The document provides guidance on preparing a job search for 2024. It discusses the state of the job market, focusing on growth in AI and healthcare but also continued layoffs. It recommends figuring out what you want to do by researching interests and skills, then conducting informational interviews. The job search should involve building a personal brand on LinkedIn, actively applying to jobs, tailoring resumes and interviews, maintaining job hunting as a habit, and continuing self-improvement. Once hired, the document advises setting new goals and keeping skills and networking active in case of future opportunities.
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
The document provides career advice for getting into the tech field, including:
- Doing projects and internships in college to build a portfolio.
- Learning about different roles and technologies through industry research.
- Contributing to open source projects to build experience and network.
- Developing a personal brand through a website and social media presence.
- Networking through events, communities, and finding a mentor.
- Practicing interviews through mock interviews and whiteboarding coding questions.
Google's Just Not That Into You: Understanding Core Updates & Search IntentLily Ray
1. Core updates from Google periodically change how its algorithms assess and rank websites and pages. This can impact rankings through shifts in user intent, site quality issues being caught up to, world events influencing queries, and overhauls to search like the E-A-T framework.
2. There are many possible user intents beyond just transactional, navigational and informational. Identifying intent shifts is important during core updates. Sites may need to optimize for new intents through different content types and sections.
3. Responding effectively to core updates requires analyzing "before and after" data to understand changes, identifying new intents or page types, and ensuring content matches appropriate intents across video, images, knowledge graphs and more.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...Applitools
During this webinar, Anand Bagmar demonstrates how AI tools such as ChatGPT can be applied to various stages of the software development life cycle (SDLC) using an eCommerce application case study. Find the on-demand recording and more info at https://applitools.info/b59
Key takeaways:
• Learn how to use ChatGPT to add AI power to your testing and test automation
• Understand the limitations of the technology and where human expertise is crucial
• Gain insight into different AI-based tools
• Adopt AI-based tools to stay relevant and optimize work for developers and testers
* ChatGPT and OpenAI belong to OpenAI, L.L.C.
The document discusses various AI tools from OpenAI like GPT-3 and DALL-E 2, as well as ChatGPT. It explores how search engines are using AI and things to consider around AI-generated content. Potential SEO uses of ChatGPT are also presented, such as generating content at scale, conducting topic research, and automating basic coding tasks. The document encourages further reading on using ChatGPT for SEO purposes.
More than Just Lines on a Map: Best Practices for U.S Bike Routes
This session highlights best practices and lessons learned for U.S. Bike Route System designation, as well as how and why these routes should be integrated into bicycle planning at the local and regional level.
Presenters:
Presenter: Kevin Luecke Toole Design Group
Co-Presenter: Virginia Sullivan Adventure Cycling Association
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...DevGAMM Conference
Has your project been caught in a storm of deadlines, clashing requirements, and the need to change course halfway through? If yes, then check out how the administration team navigated through all of this, relocating 160 people from 3 countries and opening 2 offices during the most turbulent time in the last 20 years. Belka Games’ Chief Administrative Officer, Katerina Rudko, will share universal approaches and life hacks that can help your project survive unstable periods when there seem to be too many tasks and a lack of time and people.
This presentation was designed to provide strategic recommendations for a brand in decline. The deck also incorporates a situational assessment, including a brand identity, positioning, architecture, and portfolio strategy for the Brand.
Presentation originally created for NYU Stern's Brand Strategy course. Design by Erica Santiago & Chris Alexander.
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them wellSaba Software
According to the latest State of the American Manager report from Gallup, employees who have regular meetings with their managers are almost three times as likely to be engaged as those who don’t. These regular check-ins keep managers and employees in sync and aligned. Want to see better manager/employee relationships in your organisation? Then make an all-in commitment to 1:1 meetings. Not sure how? You’ve come to the right place.
In this webinar with Jamie Resker, Founder and Practice Leader for Employee Performance Solutions (EPS), and Teala Wilson, Talent Management Consultant at Saba Software, you’ll get the inside track on how to hold effective 1:1 meetings, including tips for getting managers on board.
• Go beyond discussing the status of everyday work to higher level topics, including recognition, performance, development, and career aspirations
• Learn how to decide meeting frequency, what to cover, as well as roles and responsibilities of the manager and employee
• Understand how managers can build trust and make it comfortable for employees to provide upward feedback
• Unite your organisation with a unified approach to 1:1 meetings
Join us for this 1-hour webinar to get practical tips for building better manager-employee relationships with intention and purpose.
About the Speakers
Jamie Resker - Founder and Practice Leader for Employee Performance Solutions (EPS)
Jamie Resker, Practice Leader and Founder of Employee Performance Solutions, is a recognized innovator in performance management. She is the originator of the-the Performance Continuum Feedback Method® and Conversations to Optimize Employee Performance training program; tools and training that reshape communications between managers and employees to drive and align performance. Jamie is on the faculty for the Northeast Human Resources Association, is a contributor to Halogen Software's Talent Space Blog, and is an editorial advisory board member for HR Examiner.
Teala Wilson - Senior Consultant, Strategic Services, Saba Software
Teala is a Talent Management Consultant at Halogen Software, now a part of Saba Software. She has worked with teams on a national and global level supporting human resources in areas such as performance management, recruitment, employee benefit programs, training and talent development, workforce planning and internal communications. Teala also has a personal passion for visual arts and design.
Want to learn more? Join us for an upcoming Product Tour!
http://bit.ly/2yitfqu
Content Methodology: A Best Practices Report (Webinar)contently
This document provides an overview of content methodology best practices. It defines content methodology as establishing objectives, KPIs, and a culture of continuous learning and iteration. An effective methodology focuses on connecting with audiences, creating optimal content, and optimizing processes. It also discusses why a methodology is needed due to the competitive landscape, proliferation of channels, and opportunities for improvement. Components of an effective methodology include defining objectives and KPIs, audience analysis, identifying opportunities, and evaluating resources. The document concludes with recommendations around creating a content plan, testing and optimizing content over 90 days.
How to Prepare For a Successful Job Search for 2024Albert Qian
The document provides guidance on preparing a job search for 2024. It discusses the state of the job market, focusing on growth in AI and healthcare but also continued layoffs. It recommends figuring out what you want to do by researching interests and skills, then conducting informational interviews. The job search should involve building a personal brand on LinkedIn, actively applying to jobs, tailoring resumes and interviews, maintaining job hunting as a habit, and continuing self-improvement. Once hired, the document advises setting new goals and keeping skills and networking active in case of future opportunities.
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
The document provides career advice for getting into the tech field, including:
- Doing projects and internships in college to build a portfolio.
- Learning about different roles and technologies through industry research.
- Contributing to open source projects to build experience and network.
- Developing a personal brand through a website and social media presence.
- Networking through events, communities, and finding a mentor.
- Practicing interviews through mock interviews and whiteboarding coding questions.
Google's Just Not That Into You: Understanding Core Updates & Search IntentLily Ray
1. Core updates from Google periodically change how its algorithms assess and rank websites and pages. This can impact rankings through shifts in user intent, site quality issues being caught up to, world events influencing queries, and overhauls to search like the E-A-T framework.
2. There are many possible user intents beyond just transactional, navigational and informational. Identifying intent shifts is important during core updates. Sites may need to optimize for new intents through different content types and sections.
3. Responding effectively to core updates requires analyzing "before and after" data to understand changes, identifying new intents or page types, and ensuring content matches appropriate intents across video, images, knowledge graphs and more.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...Applitools
During this webinar, Anand Bagmar demonstrates how AI tools such as ChatGPT can be applied to various stages of the software development life cycle (SDLC) using an eCommerce application case study. Find the on-demand recording and more info at https://applitools.info/b59
Key takeaways:
• Learn how to use ChatGPT to add AI power to your testing and test automation
• Understand the limitations of the technology and where human expertise is crucial
• Gain insight into different AI-based tools
• Adopt AI-based tools to stay relevant and optimize work for developers and testers
* ChatGPT and OpenAI belong to OpenAI, L.L.C.
The document discusses various AI tools from OpenAI like GPT-3 and DALL-E 2, as well as ChatGPT. It explores how search engines are using AI and things to consider around AI-generated content. Potential SEO uses of ChatGPT are also presented, such as generating content at scale, conducting topic research, and automating basic coding tasks. The document encourages further reading on using ChatGPT for SEO purposes.
More than Just Lines on a Map: Best Practices for U.S Bike Routes
This session highlights best practices and lessons learned for U.S. Bike Route System designation, as well as how and why these routes should be integrated into bicycle planning at the local and regional level.
Presenters:
Presenter: Kevin Luecke Toole Design Group
Co-Presenter: Virginia Sullivan Adventure Cycling Association
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...DevGAMM Conference
Has your project been caught in a storm of deadlines, clashing requirements, and the need to change course halfway through? If yes, then check out how the administration team navigated through all of this, relocating 160 people from 3 countries and opening 2 offices during the most turbulent time in the last 20 years. Belka Games’ Chief Administrative Officer, Katerina Rudko, will share universal approaches and life hacks that can help your project survive unstable periods when there seem to be too many tasks and a lack of time and people.
This presentation was designed to provide strategic recommendations for a brand in decline. The deck also incorporates a situational assessment, including a brand identity, positioning, architecture, and portfolio strategy for the Brand.
Presentation originally created for NYU Stern's Brand Strategy course. Design by Erica Santiago & Chris Alexander.
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them wellSaba Software
According to the latest State of the American Manager report from Gallup, employees who have regular meetings with their managers are almost three times as likely to be engaged as those who don’t. These regular check-ins keep managers and employees in sync and aligned. Want to see better manager/employee relationships in your organisation? Then make an all-in commitment to 1:1 meetings. Not sure how? You’ve come to the right place.
In this webinar with Jamie Resker, Founder and Practice Leader for Employee Performance Solutions (EPS), and Teala Wilson, Talent Management Consultant at Saba Software, you’ll get the inside track on how to hold effective 1:1 meetings, including tips for getting managers on board.
• Go beyond discussing the status of everyday work to higher level topics, including recognition, performance, development, and career aspirations
• Learn how to decide meeting frequency, what to cover, as well as roles and responsibilities of the manager and employee
• Understand how managers can build trust and make it comfortable for employees to provide upward feedback
• Unite your organisation with a unified approach to 1:1 meetings
Join us for this 1-hour webinar to get practical tips for building better manager-employee relationships with intention and purpose.
About the Speakers
Jamie Resker - Founder and Practice Leader for Employee Performance Solutions (EPS)
Jamie Resker, Practice Leader and Founder of Employee Performance Solutions, is a recognized innovator in performance management. She is the originator of the-the Performance Continuum Feedback Method® and Conversations to Optimize Employee Performance training program; tools and training that reshape communications between managers and employees to drive and align performance. Jamie is on the faculty for the Northeast Human Resources Association, is a contributor to Halogen Software's Talent Space Blog, and is an editorial advisory board member for HR Examiner.
Teala Wilson - Senior Consultant, Strategic Services, Saba Software
Teala is a Talent Management Consultant at Halogen Software, now a part of Saba Software. She has worked with teams on a national and global level supporting human resources in areas such as performance management, recruitment, employee benefit programs, training and talent development, workforce planning and internal communications. Teala also has a personal passion for visual arts and design.
Want to learn more? Join us for an upcoming Product Tour!
http://bit.ly/2yitfqu
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them well
Levy Processes and Applications in Finance
1. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
AnelÐxeic L´vy kai Efarmogèc sta
e
Qrhmatooikonomikˆ
Αναγνώστου Ιωάννης
Ejnikì Metsìbio PoluteqneÐo
Sqol Efarmosmènwn Majhmatik¸n kai Fusik¸n Episthm¸n
11 Νοε βρίου 2010
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
2. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
1 Εισαγωγή
2 Το Μοντέλο Black-Scholes
Μοντέλο Αγοράς
Απόκλιση από την Κανονικότητα
Τεκ αρτή Μεταβλητότητα
3 Ανελίξεις L´vy
e
Ορισ ός
Ιδιότητες
Αγορά L´vy
e
Μοντέλα ΄Απειρης ράσης
Στοχαστική Μεταβλητότητα
4 Αποτί ηση Εξωτικών ικαιω άτων Προαίρεσης
Barrier και Lookback Options
Monte Carlo Προσο οίωση
Βαθ ονό ηση
Αποτελέσ ατα
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
3. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Eisagwg
Ορισ ός (Χρη ατοοικονο ικά Παράγωγα)
Τα χρη ατοοικονο ικά παράγωγα είναι δι ερείς συ βάσεις των
οποίων η απόδοση καθορίζεται από την αξία κάποιου υποκεί ενου
αγαθού το οποίο πορεί να είναι ε πόρευ α, ετοχή, δείκτης κτλ.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
4. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Eisagwg
Ορισ ός (Χρη ατοοικονο ικά Παράγωγα)
Τα χρη ατοοικονο ικά παράγωγα είναι δι ερείς συ βάσεις των
οποίων η απόδοση καθορίζεται από την αξία κάποιου υποκεί ενου
αγαθού το οποίο πορεί να είναι ε πόρευ α, ετοχή, δείκτης κτλ.
Ση αντικότεροι τύποι χρη ατοοικονο ικών παραγώγων
Προθεσ ιακά Συ βόλαια (Forwards)
Συ βόλαια Μελλοντικής Εκπλήρωσης (Futures)
ικαιώ ατα Προαίρεσης (Options)
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
5. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Ορισ ός ( ικαίω α Προαίρεσης)
ικαίω α προαίρεσης (Option) είναι ένα συ βόλαιο εταξύ δύο
αντισυ βαλλο ένων το οποίο δίνει στον αγοραστή (holder) το
δικαίω α και όχι την υποχρέωση να αγοράσει ή να πωλήσει, ανάλογα
ε το είδος του δικαιώ ατος, από τον πωλητή (writer) του
δικαιώ ατος ένα συγκεκρι ένο αγαθό σε ία προκαθορισ ένη τι ή K ,
κατά τη διάρκεια ίας χρονικής περιόδου [0, T ] ή σε συγκεκρι ένη
χρονική στιγ ή T στο έλλον.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
6. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Ορισ ός ( ικαίω α Προαίρεσης)
ικαίω α προαίρεσης (Option) είναι ένα συ βόλαιο εταξύ δύο
αντισυ βαλλο ένων το οποίο δίνει στον αγοραστή (holder) το
δικαίω α και όχι την υποχρέωση να αγοράσει ή να πωλήσει, ανάλογα
ε το είδος του δικαιώ ατος, από τον πωλητή (writer) του
δικαιώ ατος ένα συγκεκρι ένο αγαθό σε ία προκαθορισ ένη τι ή K ,
κατά τη διάρκεια ίας χρονικής περιόδου [0, T ] ή σε συγκεκρι ένη
χρονική στιγ ή T στο έλλον.
Ση αντικότεροι τύποι δικαιω άτων προαίρεσης
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
7. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Ορισ ός ( ικαίω α Προαίρεσης)
ικαίω α προαίρεσης (Option) είναι ένα συ βόλαιο εταξύ δύο
αντισυ βαλλο ένων το οποίο δίνει στον αγοραστή (holder) το
δικαίω α και όχι την υποχρέωση να αγοράσει ή να πωλήσει, ανάλογα
ε το είδος του δικαιώ ατος, από τον πωλητή (writer) του
δικαιώ ατος ένα συγκεκρι ένο αγαθό σε ία προκαθορισ ένη τι ή K ,
κατά τη διάρκεια ίας χρονικής περιόδου [0, T ] ή σε συγκεκρι ένη
χρονική στιγ ή T στο έλλον.
Ση αντικότεροι τύποι δικαιω άτων προαίρεσης
Plain Vanilla Options
EurwpaðkoÔ TÔpou
AmerikanikoÔ TÔpou
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
8. Eisagwg
To Montèlo Black-Scholes
AnelÐxeic L´vy
e
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Ορισ ός ( ικαίω α Προαίρεσης)
ικαίω α προαίρεσης (Option) είναι ένα συ βόλαιο εταξύ δύο
αντισυ βαλλο ένων το οποίο δίνει στον αγοραστή (holder) το
δικαίω α και όχι την υποχρέωση να αγοράσει ή να πωλήσει, ανάλογα
ε το είδος του δικαιώ ατος, από τον πωλητή (writer) του
δικαιώ ατος ένα συγκεκρι ένο αγαθό σε ία προκαθορισ ένη τι ή K ,
κατά τη διάρκεια ίας χρονικής περιόδου [0, T ] ή σε συγκεκρι ένη
χρονική στιγ ή T στο έλλον.
Ση αντικότεροι τύποι δικαιω άτων προαίρεσης
Plain Vanilla Options
EurwpaðkoÔ TÔpou
AmerikanikoÔ TÔpou
Exotic Options
AsiatikoÔ TÔpou
Lookback Options
Barrier Options
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
9. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
To Montèlo Black-Scholes
Θεωρού ε ια αγορά στην οποία οι επενδυτές πορούν να
συναλλάσσονται συνεχώς στο χρονικό διάστη α [0, T ] για κάποιο
δεδο ένο T . Στην αγορά αυτή διατίθενται οι παρακάτω τίτλοι:
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
10. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
To Montèlo Black-Scholes
Θεωρού ε ια αγορά στην οποία οι επενδυτές πορούν να
συναλλάσσονται συνεχώς στο χρονικό διάστη α [0, T ] για κάποιο
δεδο ένο T . Στην αγορά αυτή διατίθενται οι παρακάτω τίτλοι:
(i) Ο τίτλος 1 (riskless asset). Μια επένδυση στη αγορά χρή ατος
ε σταθερό επιτόκιο r . Η ανέλιξη της αξίας του στο χρόνο t
είναι b = {b(t) = e rt , 0 ≤ t ≤ T }.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
11. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
To Montèlo Black-Scholes
Θεωρού ε ια αγορά στην οποία οι επενδυτές πορούν να
συναλλάσσονται συνεχώς στο χρονικό διάστη α [0, T ] για κάποιο
δεδο ένο T . Στην αγορά αυτή διατίθενται οι παρακάτω τίτλοι:
(i) Ο τίτλος 1 (riskless asset). Μια επένδυση στη αγορά χρή ατος
ε σταθερό επιτόκιο r . Η ανέλιξη της αξίας του στο χρόνο t
είναι b = {b(t) = e rt , 0 ≤ t ≤ T }.
(ii) Ο τίτλος 2 (risky asset). Μια ετοχή η οποία σε χρόνο t έχει
αξία St . Θεωρού ε ότι η στοχαστική ανέλιξη {St , 0 ≤ t ≤ T }
είναι ια γεω ετρική κίνηση Brown ε αρχική τι ή S0 , δηλαδή
1
St = S0 exp((µ − 2 σ 2 )t + σWt ), όπου Wt τυπική κίνηση Brown, µ
(drift) ο συντελεστής του έσου όρου της ανάπτυξης των τι ών
και σ (volatility) η εταβλητότητα.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
12. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Παρατήρηση 1
Παρατηρού ε ότι η
logSt − logS0 = (µ − 1 σ 2 )t + σWt
2
ακολουθεί Κανονική κατανο ή N(t(µ − 1 σ 2 ), σ 2 t). ς αποτέλεσ α, η
2
St ακολουθεί λογαριθ οκανονική (lognormal) κατανο ή.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
13. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Παρατήρηση 1
Παρατηρού ε ότι η
logSt − logS0 = (µ − 1 σ 2 )t + σWt
2
ακολουθεί Κανονική κατανο ή N(t(µ − 1 σ 2 ), σ 2 t). ς αποτέλεσ α, η
2
St ακολουθεί λογαριθ οκανονική (lognormal) κατανο ή.
Παρατήρηση 2
Η παρά ετρος αβεβαιότητας για τη ελλοντική πορεία των τι ών του
υποκεί ενου τίτλου σ (volatility) υποτίθεται σταθερή.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
15. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
PÐnakac: AsummetrÐa kai Kurtìthta kuriìterwn deikt¸n
είκτης Ασυ ετρία Κυρτότητα
SP 500 -0.4423 6.96
Nasdaq-composite -0.5474 5.81
DAX -0.4329 4.67
SMI -0.3595 5.40
CAC-40 -0.2123 4.64
PÐnakac: Normal χ2 -test: R-timèc kai ìria klˆsewn
είκτης Ρ-τι ή ΄Ορια κλάσεων
SP 500 0.0421 -0.0300+0.0015i, i = 0,..., 40
Nasdaq-Composite 0.0049 -0.0300+0.0020i, i = 0,..., 30
DAX 0.0366 -0.0225+0.0015i, i = 0,..., 30
SMI 0.0479 -0.0180+0.0012i, i = 0,..., 30
CAC-40 0.0285 -0.0180+0.0012i, i = 0,..., 30
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
16. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Ορισ ός
Τεκ αρτή εταβλητότητα (implied volatility), για ένα
συγκεκρι ένο δικαίω α προαίρεσης, είναι η τι ή της εταβλητότητας
που αν εισαχθεί στο οντέλο Black-Scholes, εξισώνει τη θεωρητική
τι ή του δικαιώ ατος ε την τι ή της αγοράς.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
17. Eisagwg
Montèlo Agorˆc
To Montèlo Black-Scholes
Apìklish apì thn Kanonikìthta
AnelÐxeic L´vy
e
Tekmart Metablhtìthta
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Ορισ ός
Τεκ αρτή εταβλητότητα (implied volatility), για ένα
συγκεκρι ένο δικαίω α προαίρεσης, είναι η τι ή της εταβλητότητας
που αν εισαχθεί στο οντέλο Black-Scholes, εξισώνει τη θεωρητική
τι ή του δικαιώ ατος ε την τι ή της αγοράς.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
18. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
AnelÐxeic L´vy
e
Ορισ ός (Ανέλιξη L´vy)
e
Μια προσαρ οσ ένη, ε τι ές στον Rd στοχαστική ανέλιξη
L = (Lt )t≥0 , ε L0 = 0 σ.β. καλείται ανέλιξη L´vy αν:
e
΄Εχει ανεξάρτητες προσαυξήσεις
΄Εχει στάσι ες προσαυξήσεις
Είναι στοχαστικά συνεχής
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
19. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
AnelÐxeic L´vy
e
Ορισ ός (Ανέλιξη L´vy)
e
Μια προσαρ οσ ένη, ε τι ές στον Rd στοχαστική ανέλιξη
L = (Lt )t≥0 , ε L0 = 0 σ.β. καλείται ανέλιξη L´vy αν:
e
΄Εχει ανεξάρτητες προσαυξήσεις
Για κάθε n ≥ 1 και 0 ≤ t0 ≤ t1 ≤ ... ≤ tn , οι τ. .
Lt0 , Lt1 − Lt0 , ..., Ltn − Ltn−1 είναι ανεξάρτητες
΄Εχει στάσι ες προσαυξήσεις
Είναι στοχαστικά συνεχής
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
20. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
AnelÐxeic L´vy
e
Ορισ ός (Ανέλιξη L´vy)
e
Μια προσαρ οσ ένη, ε τι ές στον Rd στοχαστική ανέλιξη
L = (Lt )t≥0 , ε L0 = 0 σ.β. καλείται ανέλιξη L´vy αν:
e
΄Εχει ανεξάρτητες προσαυξήσεις
Για κάθε n ≥ 1 και 0 ≤ t0 ≤ t1 ≤ ... ≤ tn , οι τ. .
Lt0 , Lt1 − Lt0 , ..., Ltn − Ltn−1 είναι ανεξάρτητες
΄Εχει στάσι ες προσαυξήσεις
Για κάθε s, t ≥ 1 η κατανο ή της Xt+s − Xs δεν εξαρτάται από το
s
Είναι στοχαστικά συνεχής
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
21. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
AnelÐxeic L´vy
e
Ορισ ός (Ανέλιξη L´vy)
e
Μια προσαρ οσ ένη, ε τι ές στον Rd στοχαστική ανέλιξη
L = (Lt )t≥0 , ε L0 = 0 σ.β. καλείται ανέλιξη L´vy αν:
e
΄Εχει ανεξάρτητες προσαυξήσεις
Για κάθε n ≥ 1 και 0 ≤ t0 ≤ t1 ≤ ... ≤ tn , οι τ. .
Lt0 , Lt1 − Lt0 , ..., Ltn − Ltn−1 είναι ανεξάρτητες
΄Εχει στάσι ες προσαυξήσεις
Για κάθε s, t ≥ 1 η κατανο ή της Xt+s − Xs δεν εξαρτάται από το
s
Είναι στοχαστικά συνεχής
Για κάθε t ≥ 0 και ε > 0 ισχύει lim P(|Xs − Xt | > ε) = 0
s→t
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
22. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
AnelÐxeic L´vy
e
Ορισ ός (Ανέλιξη L´vy)
e
Μια προσαρ οσ ένη, ε τι ές στον Rd στοχαστική ανέλιξη
L = (Lt )t≥0 , ε L0 = 0 σ.β. καλείται ανέλιξη L´vy αν:
e
΄Εχει ανεξάρτητες προσαυξήσεις
Για κάθε n ≥ 1 και 0 ≤ t0 ≤ t1 ≤ ... ≤ tn , οι τ. .
Lt0 , Lt1 − Lt0 , ..., Ltn − Ltn−1 είναι ανεξάρτητες
΄Εχει στάσι ες προσαυξήσεις
Για κάθε s, t ≥ 1 η κατανο ή της Xt+s − Xs δεν εξαρτάται από το
s
Είναι στοχαστικά συνεχής
Για κάθε t ≥ 0 και ε > 0 ισχύει lim P(|Xs − Xt | > ε) = 0
s→t
Το ενδιαφέρον ας επικεντρώνεται στην περίπτωση που η L παίρνει
τι ές στον χώρο R των πραγ ατικών αριθ ών
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
23. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια συνάρτηση f : [0, T ] −→ Rd λέγεται c`dl`g (continu ` droite,
a a a
limite ` gauche) αν για κάθε t ∈ [0, T ] τα όρια
a
f (t−) = lim f (s) f (t+) = lim f (s)
s→t,s<t s→t,s>t
υπάρχουν και f (t) = f (t+).
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
24. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια συνάρτηση f : [0, T ] −→ Rd λέγεται c`dl`g (continu ` droite,
a a a
limite ` gauche) αν για κάθε t ∈ [0, T ] τα όρια
a
f (t−) = lim f (s) f (t+) = lim f (s)
s→t,s<t s→t,s>t
υπάρχουν και f (t) = f (t+).
Στη συνέχεια θα υποθέτου ε πάντα ότι οι τριχιές της L είναι c`dl`g.
a a
Η αιτιολόγηση προκύπτει ά εσα από τα επό ενα δύο αποτελέσ ατα.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
25. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Λή α
Αν L είναι ια ανέλιξη L´vy και M είναι ια τροποποίηση της L (δηλ.
e
P(Lt = Mt ) = 0 σ.β. για κάθε t ≥ 0), τότε η M είναι ανέλιξη L´vy και
e
έχει τα ίδια χαρακτηριστικά ε την L.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
26. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Λή α
Αν L είναι ια ανέλιξη L´vy και M είναι ια τροποποίηση της L (δηλ.
e
P(Lt = Mt ) = 0 σ.β. για κάθε t ≥ 0), τότε η M είναι ανέλιξη L´vy και
e
έχει τα ίδια χαρακτηριστικά ε την L.
Θεώρη α
Κάθε ανέλιξη L´vy έχει ια οναδική c`dl`g τροποποίηση, η οποία
e a a
είναι ανέλιξη L´vy.
e
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
27. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια τ. . X έχει απείρως διαιρετή κατανο ή αν για κάθε n ∈ N
υπάρχει ια ακολουθία ανεξάρτητων και ισόνο ων τυχαίων
(1/n) (1/n) (1/n)
εταβλητών X1 , X2 , ..., Xn τέτοια ώστε:
d (1/n) (1/n) (1/n)
X = X1 + X2 + ... + Xn
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
28. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια τ. . X έχει απείρως διαιρετή κατανο ή αν για κάθε n ∈ N
υπάρχει ια ακολουθία ανεξάρτητων και ισόνο ων τυχαίων
(1/n) (1/n) (1/n)
εταβλητών X1 , X2 , ..., Xn τέτοια ώστε:
d (1/n) (1/n) (1/n)
X = X1 + X2 + ... + Xn
Εναλλακτικά, ε χρήση της χαρακτηριστικής της συνάρτησης
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
29. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια τ. . X έχει απείρως διαιρετή κατανο ή αν για κάθε n ∈ N
υπάρχει ια ακολουθία ανεξάρτητων και ισόνο ων τυχαίων
(1/n) (1/n) (1/n)
εταβλητών X1 , X2 , ..., Xn τέτοια ώστε:
d (1/n) (1/n) (1/n)
X = X1 + X2 + ... + Xn
Εναλλακτικά, ε χρήση της χαρακτηριστικής της συνάρτησης
Ορισ ός
Μια τ. . X έχει απείρως διαιρετή κατανο ή αν, για κάθε n ∈ N
υπάρχει τυχαία εταβλητή X (1/n) τέτοια ώστε
φX (u) = (φX (1/n) (u))n
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
30. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Παράδειγ α
΄Εστω η τ. . X , όπου X ∼ N(µ, σ 2 ). Τότε η X γράφεται:
n−1 (1/n)
X = k=0 Yk
(1/n)
όπου Yk τυχαίες εταβλητές, ανεξάρτητες και ισόνο ες, που
µ σ2
ακολουθούν την κατανο ή N , . Επο ένως, η κανονική
n n
κατανο ή ανήκει στην κλάση των απείρως διαιρετών κατανο ών.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
31. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Παράδειγ α
΄Εστω η τ. . X , όπου X ∼ N(µ, σ 2 ). Τότε η X γράφεται:
n−1 (1/n)
X = k=0 Yk
(1/n)
όπου Yk τυχαίες εταβλητές, ανεξάρτητες και ισόνο ες, που
µ σ2
ακολουθούν την κατανο ή N , . Επο ένως, η κανονική
n n
κατανο ή ανήκει στην κλάση των απείρως διαιρετών κατανο ών.
΄Αλλα παραδείγ ατα απείρως διαιρετών κατανο ών είναι η Poisson,
Εκθετική, η Γά α, η Γεω ετρική και η Cauchy. Αντιπαραδείγ ατα
είναι η Ο οιό ορφη και η ιωνυ ική κατανο ή.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
32. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
΄Εστω ν ένα έτρο Borel στον Rd . Το ν λέγεται έτρο L´vy αν
e
ικανοποιεί τα ακόλουθα:
2
ν ({0}) = 0 και 1∧ x ν(dx) < ∞
Rd
όπου ο συ βολισ ός 1 ∧ x 2 δηλώνει το inf 1, x 2 .
Το έτρο L´vy εκφράζει την ανα ενό ενη τι ή του πλήθους αλ άτων
e
συγκεκρι ένου εγέθους, σε ένα χρονικό διάστη α ήκους ιας
ονάδας, δηλαδή αν (Lt )t≥0 ια ανέλιξη L´vy τότε:
e
ν (A) = E [# {t ∈ [0, 1] : ∆Lt = 0, ∆Lt ∈ A}] , A ∈ B Rd
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
33. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Θεώρη α(L´vy-Khintchine)
e
΄Εστω X ια τ. ., ορισ ένη στο χ.π. (Ω, F, P) και ψ(u) ο λογάριθ ος
της χαρακτηριστικής συνάρτησης φX (u). Η X έχει απείρως διαιρετή
κατανο ή αν και όνο αν υπάρχει ια τριπλέτα σ 2 , γ, ν(dx) , όπου
σ 2 ένας συ ετρικός, η αρνητικά ορισ ένος d × d πίνακας, γ ∈ Rd
και ν ένα έτρο L´vy, τέτοια ώστε:
e
1
ψ(u) = i u, γ − u, σ 2 u
2
+ ei u,x
− 1 − i u, x 1S[0,1] ν(dx)
Rd
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
34. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Θεώρη α(L´vy-Khintchine)
e
΄Εστω X ια τ. ., ορισ ένη στο χ.π. (Ω, F, P) και ψ(u) ο λογάριθ ος
της χαρακτηριστικής συνάρτησης φX (u). Η X έχει απείρως διαιρετή
κατανο ή αν και όνο αν υπάρχει ια τριπλέτα σ 2 , γ, ν(dx) , όπου
σ 2 ένας συ ετρικός, η αρνητικά ορισ ένος d × d πίνακας, γ ∈ Rd
και ν ένα έτρο L´vy, τέτοια ώστε:
e
1
ψ(u) = i u, γ − u, σ 2 u
2
+ ei u,x
− 1 − i u, x 1S[0,1] ν(dx)
Rd
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
35. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Θεώρη α(L´vy-Khintchine)
e
΄Εστω X ια τ. ., ορισ ένη στο χ.π. (Ω, F, P) και ψ(u) ο λογάριθ ος
της χαρακτηριστικής συνάρτησης φX (u). Η X έχει απείρως διαιρετή
κατανο ή αν και όνο αν υπάρχει ια τριπλέτα σ 2 , γ, ν(dx) , όπου
σ 2 ένας συ ετρικός, η αρνητικά ορισ ένος d × d πίνακας, γ ∈ Rd
και ν ένα έτρο L´vy, τέτοια ώστε:
e
1
ψ(u) = i u, γ − u, σ 2 u
2
+ ei u,x
− 1 − i u, x 1S[0,1] ν(dx)
Rd
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
36. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Θεώρη α(L´vy-Khintchine)
e
΄Εστω X ια τ. ., ορισ ένη στο χ.π. (Ω, F, P) και ψ(u) ο λογάριθ ος
της χαρακτηριστικής συνάρτησης φX (u). Η X έχει απείρως διαιρετή
κατανο ή αν και όνο αν υπάρχει ια τριπλέτα σ 2 , γ, ν(dx) , όπου
σ 2 ένας συ ετρικός, η αρνητικά ορισ ένος d × d πίνακας, γ ∈ Rd
και ν ένα έτρο L´vy, τέτοια ώστε:
e
1
ψ(u) = i u, γ − u, σ 2 u
2
+ ei u,x
− 1 − i u, x 1S[0,1] ν(dx)
Rd
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
37. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Θεώρη α(L´vy-Khintchine)
e
΄Εστω X ια τ. ., ορισ ένη στο χ.π. (Ω, F, P) και ψ(u) ο λογάριθ ος
της χαρακτηριστικής συνάρτησης φX (u). Η X έχει απείρως διαιρετή
κατανο ή αν και όνο αν υπάρχει ια τριπλέτα σ 2 , γ, ν(dx) , όπου
σ 2 ένας συ ετρικός, η αρνητικά ορισ ένος d × d πίνακας, γ ∈ Rd
και ν ένα έτρο L´vy, τέτοια ώστε:
e
1
ψ(u) = i u, γ − u, σ 2 u
2
+ ei u,x
− 1 − i u, x 1S[0,1] ν(dx)
Rd
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
38. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
΄Εστω τώρα ια ανέλιξη L´vy L = (Lt )t≥0 . Για κάθε n ∈ N και t > 0,
e
Lt = Lt/n + L2t/n − Lt/n + ... + Lt − L(n−1)t/n
Σε συνδυασ ό ε την ανεξαρτησία και τη στασι ότητα των
προσαυξήσεων, συ περαίνου ε ότι η τ. . Lt είναι απείρως διαιρετή.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
39. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
΄Εστω τώρα ια ανέλιξη L´vy L = (Lt )t≥0 . Για κάθε n ∈ N και t > 0,
e
Lt = Lt/n + L2t/n − Lt/n + ... + Lt − L(n−1)t/n
Σε συνδυασ ό ε την ανεξαρτησία και τη στασι ότητα των
προσαυξήσεων, συ περαίνου ε ότι η τ. . Lt είναι απείρως διαιρετή.
L´vy-Khintchine Αναπαράσταση
e
΄Εστω (Lt )t≥0 ια ανέλιξη L´vy. Η χαρακτηριστική της συνάρτηση
e
ικανοποιεί την ακόλουθη σχέση
E e iuLt = e tψ(u)
1
= exp t i u, γ − u, σ 2 u
2
+ ei u,x
− 1 − i u, x 1S[0,1] ν(dx)
Rd
όπου ψ(u) := ψ1 (u) ο λογάριθ ος της τυχαίας εταβλητής ε απείρως
διαιρετή κατανο ή L1 := X .
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
40. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Θεώρη α (L´vy-Itˆ
e o ιαχώριση)
΄Εστω ια τριπλέτα L´vy (σ 2 , γ, ν) όπου σ 2 ∈ Sd , γ ∈ Rd και ν έτρο
e ≥0
L´vy . Τότε υπάρχουν στον ίδιο χ.π. τρεις ανεξάρτητες ανελίξεις L´vy
e e
L(1) , L(2) και L(3) όπου
L(1) είναι ια κίνηση Brown ε γρα ική τάση
(2)
L είναι ια σύνθετη ανέλιξη Poisson
(3)
L είναι ια τετραγωνικά ολοκληρώσι η martingale ανέλιξη που
πραγ ατοποιεί σ.β. αριθ ήσι α το πλήθος άλ ατα, εγέθους
ικρότερου της ονάδας σε κάθε πεπερασ ένο χρονικό διάστη α.
Θέτοντας
(1) (2) (3)
Lt = Lt + Lt + Lt
για κάθε t ≥ 0 έχου ε ότι υπάρχει ένας χώρος πιθανότητας στον
οποίο ορίζεται ια νέα ανέλιξη L´vy (Lt )t≥0 ε χαρακτηριστική
e
τριπλέτα (σ 2 , γ, ν).
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
41. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν . Οι
e
τροχιές της L είναι συνεχείς αν και όνο αν ν ≡ 0.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
42. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν . Οι
e
τροχιές της L είναι συνεχείς αν και όνο αν ν ≡ 0.
Ορισ ός
Μια ανέλιξη L´vy L λέγεται ότι έχει άπειρη δράση (infinite activity)
e
όταν οι τροχιές της έχουν έχουν ένα σ.β. αριθ ήσι ο άπειρο πλήθος
αλ άτων σε κάθε συ παγές χρονικό διάστη α [0, T ]. Αλλιώς, λέγεται
ότι έχει πεπερασ ένη δράση (finite activity).
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
43. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
44. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Αν ν(Rd ) < ∞ τότε η L έχει πεπερασ ένη δράση (finite activity).
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
45. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Αν ν(Rd ) < ∞ τότε η L έχει πεπερασ ένη δράση (finite activity).
Αν ν(Rd ) = ∞ τότε η L έχει άπειρη δράση (infinite activity).
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
46. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Αν ν(Rd ) < ∞ τότε η L έχει πεπερασ ένη δράση (finite activity).
Αν ν(Rd ) = ∞ τότε η L έχει άπειρη δράση (infinite activity).
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
47. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Αν ν(Rd ) < ∞ τότε η L έχει πεπερασ ένη δράση (finite activity).
Αν ν(Rd ) = ∞ τότε η L έχει άπειρη δράση (infinite activity).
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Αν σ = 0 και x ≤1 x ν(dx) < ∞ τότε σχεδόν όλες οι τροχιές
της L είναι φραγ ένης κύ ανσης.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
48. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Αν ν(Rd ) < ∞ τότε η L έχει πεπερασ ένη δράση (finite activity).
Αν ν(Rd ) = ∞ τότε η L έχει άπειρη δράση (infinite activity).
Πρόταση
΄Εστω L ια ανέλιξη L´vy ε χαρακτηριστική τριπλέτα σ 2 , γ, ν .
e
Αν σ = 0 και x ≤1 x ν(dx) < ∞ τότε σχεδόν όλες οι τροχιές
της L είναι φραγ ένης κύ ανσης.
Αν σ = 0 ή x ≤1 x ν(dx) = ∞ τότε σχεδόν όλες οι τροχιές της
L είναι η φραγ ένης κύ ανσης.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
49. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
50. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
51. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
52. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Lt ≥ 0 σ.β. για κάθε t ≥ 0
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
53. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Lt ≥ 0 σ.β. για κάθε t ≥ 0
Οι τροχιές της L είναι σ.β. η-φθίνουσες: t ≥ s ⇒ Lt ≥ Ls
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
54. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Lt ≥ 0 σ.β. για κάθε t ≥ 0
Οι τροχιές της L είναι σ.β. η-φθίνουσες: t ≥ s ⇒ Lt ≥ Ls
Η τριπλέτα σ 2 , γ, ν ικανοποιεί τα ακόλουθα:
(i) σ=0
(ii) γ≥0
(iii) ν ((−∞, 0]) = 0
1
(iv) 0 xν(dx) < ∞
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
55. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Lt ≥ 0 σ.β. για κάθε t ≥ 0
Οι τροχιές της L είναι σ.β. η-φθίνουσες: t ≥ s ⇒ Lt ≥ Ls
Η τριπλέτα σ 2 , γ, ν ικανοποιεί τα ακόλουθα:
(i) σ=0
(ii) γ≥0
(iii) ν ((−∞, 0]) = 0
1
(iv) 0 xν(dx) < ∞
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
56. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Lt ≥ 0 σ.β. για κάθε t ≥ 0
Οι τροχιές της L είναι σ.β. η-φθίνουσες: t ≥ s ⇒ Lt ≥ Ls
Η τριπλέτα σ 2 , γ, ν ικανοποιεί τα ακόλουθα:
(i) σ=0
(ii) γ≥0
(iii) ν ((−∞, 0]) = 0
1
(iv) 0 xν(dx) < ∞
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
57. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Lt ≥ 0 σ.β. για κάθε t ≥ 0
Οι τροχιές της L είναι σ.β. η-φθίνουσες: t ≥ s ⇒ Lt ≥ Ls
Η τριπλέτα σ 2 , γ, ν ικανοποιεί τα ακόλουθα:
(i) σ=0
(ii) γ≥0
(iii) ν ((−∞, 0]) = 0
1
(iv) 0 xν(dx) < ∞
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
58. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ορισ ός
Μια ανέλιξη L´vy ε άυξουσες (ως προς t) τροχιές, λέγεται
e
subordinator.
Πρόταση
΄Εστω L = (Lt )t≥0 ια ανέλιξη L´vy στον R. Τα επό ενα είναι
e
ισοδύνα α:
Lt ≥ 0 σ.β. για κάποιο t ≥ 0
Lt ≥ 0 σ.β. για κάθε t ≥ 0
Οι τροχιές της L είναι σ.β. η-φθίνουσες: t ≥ s ⇒ Lt ≥ Ls
Η τριπλέτα σ 2 , γ, ν ικανοποιεί τα ακόλουθα:
(i) σ=0
(ii) γ≥0
(iii) ν ((−∞, 0]) = 0
1
(iv) 0 xν(dx) < ∞
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
59. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Qrhmatooikonomikˆ Montèla L´vy
e
Ορισ ός (Αγορά L´vy)
e
Θεωρού ε ότι για την ανέλιξη τι ής του risky asset ισχύει
St = S0 exp(Lt ), όπου L = (Lt )t≥0 ια ανέλιξη L´vy.
e
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
60. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Qrhmatooikonomikˆ Montèla L´vy
e
Ορισ ός (Αγορά L´vy)
e
Θεωρού ε ότι για την ανέλιξη τι ής του risky asset ισχύει
St = S0 exp(Lt ), όπου L = (Lt )t≥0 ια ανέλιξη L´vy.
e
Οι λογαριθ ικές αποδόσεις log (St+s /St ) ενός τέτοιου οντέλου
ακολουθούν την κατανο ή των προσαυξήσεων ήκους s της
στοχαστικής ανέλιξης L.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
61. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Qrhmatooikonomikˆ Montèla L´vy
e
Ορισ ός (Αγορά L´vy)
e
Θεωρού ε ότι για την ανέλιξη τι ής του risky asset ισχύει
St = S0 exp(Lt ), όπου L = (Lt )t≥0 ια ανέλιξη L´vy.
e
Οι λογαριθ ικές αποδόσεις log (St+s /St ) ενός τέτοιου οντέλου
ακολουθούν την κατανο ή των προσαυξήσεων ήκους s της
στοχαστικής ανέλιξης L.
˜
Η απουσία arbitrage επιβάλει ότι η St = St e −rt = e −rt e Lt είναι
martingale.
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
62. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Παρατήρηση
Το οντέλο Black-Scholes δεν είναι παρά ένα εκθετικό οντέλο L´vy,
e
1 2
όπου η ανέλιξη L είναι ια κίνηση Brown ε τάση γ = r − σ
2
Lt = γt + σWt
1
= r − σ 2 t + σWt
2
τότε
St = S0 exp (Lt )
1
= S0 exp r − σ 2 t + σWt
2
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
63. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Στα περισσότερα ρεαλιστικά οντέλα δεν υπάρχει οναδικό
ισοδύνα ο martingale έτρο: τα προτεινό ενα οντέλα L´vy είναι
e
η-πλήρη
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
64. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Στα περισσότερα ρεαλιστικά οντέλα δεν υπάρχει οναδικό
ισοδύνα ο martingale έτρο: τα προτεινό ενα οντέλα L´vy είναι
e
η-πλήρη
Mean Correcting Method
Η παρά ετρος τάσης m ∈ R αντικαθίσταται ε ια νέα
παρά ετρο ώστε η επικαιροποιη ένη ανέλιξη τι ής να είναι
martingale.
Η νέα παρά ετρος θα είναι
mnew = mold + r − q − log φ(−i)
όπου φ(x) η χαρακτηριστική συνάρτηση της στοχαστικής
ανέλιξης που περιέχει την παρά ετρο mold .
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
65. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Η κατανο ή Γά α G (a, b), όπου a, b > 0 έχει χαρακτηριστική
συνάρτηση.
−a
iu
φG (u; a, b) = 1−
b
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
66. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Η κατανο ή Γά α G (a, b), όπου a, b > 0 έχει χαρακτηριστική
συνάρτηση.
−a
iu
φG (u; a, b) = 1−
b
Ορισ ός (Ανέλιξη Γά α)
(G )
Η ανέλιξη Γά α L(G ) = Lt ορίζεται ως η στοχαστική
t≥0
ανέλιξη ε αρχή το 0, η οποία έχει στάσι ες και ανεξάρτητες
προσαυξήσεις, που ακολουθούν την κατανο ή G (a, b).
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
67. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Η κατανο ή Γά α G (a, b), όπου a, b > 0 έχει χαρακτηριστική
συνάρτηση.
−a
iu
φG (u; a, b) = 1−
b
Ορισ ός (Ανέλιξη Γά α)
(G )
Η ανέλιξη Γά α L(G ) = Lt ορίζεται ως η στοχαστική
t≥0
ανέλιξη ε αρχή το 0, η οποία έχει στάσι ες και ανεξάρτητες
προσαυξήσεις, που ακολουθούν την κατανο ή G (a, b).
(G )
Η Lt ∼ G (at, b) και η χαρακτηριστική της συνάρτηση δίνεται από τη
σχέση
(G )
(G )
E e iuLt = φt (u; at, b)
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
68. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Ακατάλληλη για τη οντελοποίηση του risky asset
Ιδανική ως subordinator
Sq ma: Deigmatik troqiˆ thc anèlixhc Gˆmma
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
69. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Η χαρακτηριστική συνάρτηση της κατανο ής VG (σ, ν, θ) είναι
−1/ν
1
φ(u; σ, ν, θ) = 1 − iuθν + σ 2 νu 2
2
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc
70. Orismìc
Eisagwg
Idiìthtec
To Montèlo Black-Scholes
Agorˆ L´vy
e
AnelÐxeic L´vy
e
Montèla '
Apeirhc Drˆshc
ApotÐmhsh Exwtik¸n Dikaiwmˆtwn ProaÐreshc
Stoqastik Metablhtìthta
Η χαρακτηριστική συνάρτηση της κατανο ής VG (σ, ν, θ) είναι
−1/ν
1
φ(u; σ, ν, θ) = 1 − iuθν + σ 2 νu 2
2
Ορισ ός (Ανέλιξη VG)
(VG )
Ορίζου ε ια στοχαστική ανέλιξη Lt ε ανεξάρτητες και στάσι ες
προσαυξήσεις, για την οποία οι προσαυξήσεις
(VG ) (VG ) √
Ls+t − Lt ∼ VG (σ t, ν/t, tθ) στο χρονικό διάστη α [t, s + t].
Anagn¸stou Iwˆnnhc AnelÐxeic L´vy
e kai Efarmogèc