mathematics

Karel Janeček

Karel Janeček is a mathematics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Karel Janeček rather than just read about it. In short: Karel Janeček (born 26 July 1973) is a Czech mathematician, entrepreneur, anti-corruption campaigner, creator of the D21 – Janeček method voting system and the online game Prezident 21. Early life and education Janeček was born in Plzeň.

Key takeaways

Karel Janeček belongs to mathematics; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Karel Janeček to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Karel Janeček from memory before moving on to harder problems.

Reference excerpt

Karel Janeček (born 26 July 1973) is a Czech mathematician, entrepreneur, anti-corruption campaigner, creator of the D21 – Janeček method voting system and the online game Prezident 21.

Early life and education Janeček was born in Plzeň. He graduated from the Faculty of Mathematics and Physics of Charles University in Prague in the field of probability and mathematical statistics. He is an MBA in finance graduate of Bradley University, Peoria, Illinois, US, and a PhD graduate in the field of mathematical finance of Carnegie Mellon University in Pittsburgh, Pennsylvania, US.

Academia From 2007 to 2013, Janeček lectured at the Faculty of Mathematics and Physics of Charles University in Prague. He specializes in optimal control in mathematical finance. Janeček has authored and co-authored several research articles in scientific journals in the area of applied stochastic calculus, where his work has numerous citations, such as "Optimal investment with high-watermark performance fee," SIAM Journal on Control and Optimization, 2012; "Futures trading with transaction costs," Illinois Journal of Mathematics, 2010; "Asymptotic analysis for optimal investment and consumption with transaction costs," Finance and Stochastics, 2004; and others.

Business From 1998 to 2000, Janeček worked as a mathematical analyst for the hedge fund Market Research Ltd, and from 2004 to 2005, served as Researcher in the Austrian Academy of Sciences. On the basis of his experience, he started the firm RSJ Algorithmic Trading.

Anti-corruption campaign

According to media reports, by 2013, the Czech government was "buffeted" by a series of corruption scandals that have threatened to bring it down. After Václav Klaus, then president of the republic, in his last days in office, granted amnesty to a number of people accused of corruption, Janeček financed the publishing of online videos and newspaper advertisements urging Czechs to sign a petition calling Klaus to account. The signatures were published on a website called "High Treason" in Czech. The movement convinced 28 Senators to back a proposal in the Senate for the Constitutional Court of the Czech Republic to undertake high treason proceedings against Klaus. Klaus, who was eventually not charged by the Supreme Court, had previously stated he did not regret the amnesty, and on an official visit to Slovakia dismissed the move as "political games."

Political reform In 2012, he proposed a new electoral system primarily based on a minus vote, i.e. the possibility to vote against a candidate. The idea was promoted as a part of the Positive Evolution project. In May 2013, Janecek created the electoral system D21 – Janeček method which, he argues, will bring about a major improvement comparable to "an upgrade from DOS to Windows". The main effect of D21 lies in the use of multiple votes - each voter has twice as many votes than the number of seats available to winners. More concretely, for the elections to the Chamber of Deputies, he designed two-mandate districts in which voters could use four votes, with the possibility to use one minus vote. One of the biggest projects where the D21 – Janeček method was used took place in 2016 in the city of New York. It was the largest participatory budgeting project in North America. In this project people were asked to distribute $38 million among various different projects proposed by the members of the community to improve the life in the city. 28 out of the 51 districts were involved in this voting and around 67,000 voters participated.

Sponsorship The Karel Janeček Benevolent Fund for Support of Science and Research was established in 2010 (renamed as Neuron Fund for Support of Science in 2013) a non-profit organisation, which promotes the idea of benefactors supporting the science and research in the Czech Republic. Neuron has supported a number of scientists and their projects through grants worth over 13 million Czech crowns.

Gambling

Janeček, in the 1990s, and after playing the game in various casinos in the United States and elsewhere, created a simulation software for advantage play in Blackjack, which he marketed under the brand "Statistical Blackjack Analyzer." The sim program has been praised by many gambling researchers. He has acted as a consultant for the casino games industry, including the creators of Blackjack Switch, which, before it became operational, was tested by Janeček-created software. Janeček, along with Brett Harris, Mike Canjar, Winston Yamashita, Pete Moss, Kim Lee, and other gambling theorists, contributed to the development of what has become known as "optimal betting theory", and the discovery that it is possible to calculate a true count for unbalanced counting systems in casino Blackjack. He has regularly contributed articles in gambling-research websites, such as Stanford Wong's BJ21.com. Janeček recommends treating the handling of advantage play "as just another investment".

Presidential bid On 21 January 2022, Janeček announced that he would be running in the 2023 Czech presidential election. He submitted 73,000 signatures, but this total was reduced following sample analysis to 48,000 (later the court labeled some of them as valid but he still failed to meet the criteria by 80 signatures), below the requirement. Janeček submitted a complaint to the Supreme Administrative Court. His complaint was rejected by the court on 13 December 2022. Janeček subsequently endorsed Petr Pavel in both rounds. On 3 February 2023 he submitted a complaint to the Supreme Administrative Court over the presidential election process.

Personal life Janeček has two daughters from his first marriage to Michaela, and a son from his second marriage to Mariem. Since May 2017, he has been in a relationship with Lilia Khousnoutdinova, and they have a daughter and a son. They got married first in a Buddhist wedding ceremony in Bhutan in 2017 and officially on 21 December 2021 in Prague. He is a Buddhists.

See also Kelly criterion Edward O. Thorp Claude Shannon Black–Scholes model

References

External links Personal blog Archived 2014-10-18 at the Wayback Machine (in Czech) "Anti-corruption campaigner ‘targeted’ by Prague underworld", Česká Pozice, 31 January 2012

Illustrations

Karel Janeček: SBA floppy disk — SBA floppy disk

Worked examples

Example 1 — a first encounter with Karel Janeček

Start with the simplest possible case. Write down what Karel Janeček claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In mathematics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Karel Janeček before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Karel Janeček ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Karel Janeček

In research: Karel Janeček appears in mathematics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Karel Janeček in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Karel Janeček is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1973 births, 21st-century Czech mathematicians, Bradley University alumni, so understanding it makes those chapters shorter.
In everyday life: Look for Karel Janeček outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Karel Janeček in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Karel Janeček means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Karel Janeček out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Karel Janeček in simple terms?

Karel Janeček (born 26 July 1973) is a Czech mathematician, entrepreneur, anti-corruption campaigner, creator of the D21 – Janeček method voting system and the online game Prezident 21. Early life and education Janeček was born in Plzeň.

Why does Karel Janeček matter?

Because it connects several mathematics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Karel Janeček?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Karel Janeček.