• ## Estimation of VaR and ConVaR for the stock price of the Kazakhstani company

The last decades the world economy regularly falls into this vortex of financial crises that have affected each country. It almost led to the collapse of the existing financial system, due to this fact, experts in mathematical and economic modelling have become to use methods for controlling the losses of the asset and portfolio in the financial world (Lechner, L. A., and Ovaert, T. C. (2010). There is an increasing trend towards mathematical modelling of an economic process to predict the market behaviour and an assessment of its sustainability (ibid). Having without necessary attention to control and assess properly threats, everybody understands that it is able to trigger tremendous cost in the development of the organisation or even go bankrupt.

Value at Risk (VaR) has eventually been a regular approach to catch the risk among institutions in the finance sector and its regulator (Engle, R., and Manganelli S., 2004). The model is originally applied to estimate the loss value in the investment portfolio within a given period of time as well as at a given probability of occurrence. Besides the fact of using VaR in the financial sector, there are a lot of examples of estimation of value at risk in different area such as anticipating the medical staff to develop the healthcare resource management Zinouri, N. (2016). Despite its applied primitiveness in a real experiment, the model consists of drawbacks in evaluation, (ibid).

The goal of the report is a description of the existing VaR model including one of its upgrade versions, namely, Conditional Value at Risk (CVaR). In the next section and section 3, the evaluation algorithm and testing of the model are explained. For a vivid illustration, the expected loss is estimated on the asset of one of the Kazakhstani company trading in the financial stock exchange market in a long time period. The final sections 4 and 5 discuss and demonstrate the findings of the research work.

• ## Flightradar24 — how does it work? Part 2, ADS-B protocol

I’m going to have a guess and say that everyone whose friends or family have ever flown on a plane, have used Flightradar24 — a free and convenient service for tracking flights in real time.

In the first part the basic ideas of operation were described. Now let's go further and figure out, what data is exactly transmitting and receiving between the aircraft and a ground station. We'll also decode this data using Python.
• ## Physical unclonable functions: protection for electronics against illegal copying

• Translation

Source: The online counterfeit economy: consumer electronics, a report made by CSC in 2017

Over the past 10 years, the number of fake goods in the world has doubled. This data has been published in the latest Year-End Intellectual Property Rights Review by the US Department of Homeland Security in 2016 (the most current year tracked). A lot of the counterfeiting comes from China (56%), Hong Kong (36%) and Singapore (2%). The manufacturers of original goods suffer serious losses, some of which occur on the electronics market.

Many modern products contain electronic components: clothes, shoes, watches, jewellery, cars.
Last year, direct losses from the illegal copying of consumer electronics and electronic components in the composition of other goods were about $0.5 trillion. How to solve this problem? • ## Zotero hacks: unlimited synced storage and its smooth use with rmarkdown • Tutorial Here is a bit refreshed translation of my 2015 blog post. The post shows how to organize a personal academic library of unlimited size for free. This is a funny case of a self written manual which I came back to multiple times myself and many many more times referred my friends to it, even non-Russian speakers who had to use Google Translator and infer the rest from screenshots. Finally, I decided to translate it adding some basic information on how to use Zotero with rmarkdown. # A brief (and hopefully unnecessary for you) intro of bibliographic managers Bibliographic manager is a life saver in everyday academic life. I suffer almost physical pain just thinking about colleagues who for some reason never started using one — all those excel spreadsheets with favorite citations, messy folders with PDFs, constant hours lost for the joy-killing task of manual reference list formatting. Once you start using a reference manager this all becomes a happily forgotten nightmare. • ## How Protonmail is getting censored by FSB in Russia • Translation A completely routine tech support ticket has uncovered unexpected bans of IP addresses of Protonmail — a very useful service for people valuing their Internet freedoms — in several regions of Russia. I seriously didn’t want to sensationalize the headline, but the story is so strange and inexplicable I couldn’t resist. ### TL;DR Disclaimer: the situation is still developing. There might not be anything malicious, but most likely there is. I will update the post once new information comes through. MTS and Rostelecom — two of the biggest Russian ISPs — started to block traffic to SMTP servers of the encrypted email service Protonmail according to an FSB request, with no regard for the official government registry of restricted websites. It seems like it’s been happening for a while, but no one paid special attention to it. Until now. All involved parties have received relevant requests for information which they’re obligated to reply. UPD: MTS has provided a scan of the FSB letter, which is the basis for restricting the access. Justification: the ongoing Universiade in Krasnoyarsk and “phone terrorism”. It’s supposed to prevent ProtonMail emails from going to emergency addresses of security services and schools. UPD: Protonmail was surprised by “these strange Russians” and their methods for battling fraud abuse, as well as suggested a more effective way to do it — via abuse mailbox. UPD: FSB’s justification doesn’t appear to be true: the bans broke ProtonMail’s incoming mail, rather than outgoing. UPD: Protonmail shrugged and changed the IP addresses of their MXs taking them out of the blocking after that particular FSB letter. What will happen next is open ended question. UPD: Apparently, such letter was not the only one and there is still a set of IP addresses of VOIP-services which are blocked without appropriate records in the official registry of restricted websites. • ## Pentesting Azure — Thoughts on Security in Cloud Computing A few months ago I worked with a customer on how a team should evaluate the security of their Azure implementation. I had never done a pentest(extensive security testing)on an Azure application before, so these ideas were just the thoughts off of the top of my head at that time based on my experience in security. Matt Burrough’s book, Pentesting Azure Applications, goes even deeper and it is a must-read for security experts focused in Cloud Computing, I’m reading it right now. Below I share with you these pre-book thoughts, and will compare them in a future article with the ones I will learn — or confirm — after reading Matt's book. • ## Learning to Computer: How to Gain a New Skill Most people assume that I studied computer science in university and that I’ve been coding since I was young. They’re usually surprised when I tell them that in fact I studied Marketing and Spanish and that although my brother taught me how to build a very basic web page in the early 2000s, I didn’t really start to learn to program until I was an adult with a job. The truth of the matter is that my story isn’t unique. It’s simply not true that you have to be a whiz kid who’s been coding since they were 6 years old in order if you want to be able to program as an adult. There are tons of examples of people who also don’t have a technical background who either became full time programmers or just learned a new skill they enjoy using. In this post, I’ll give you some advice that has served me well on my journey. My path is by no means the only path and depending on the situation you’re in might not be practical or right for you, but it is certainly a path, and I hope it helps you on your path to learning to computer. • ## Flightradar24 — how does it work? I’m going to hazard a guess and say that everyone whose friends or family have ever flown on a plane, have used Flightradar24 — a free and convenient service for tracking flights in real time. But, if my friends are any indication, very few people know that the service is community-driven and is supported by a group of enthusiasts gathering and sending data. Even fewer people know that anyone can join the project — including you. Let’s see how Flightradar and similar other services works. • ## How does a barcode work? Hi all! Every person is using barcodes nowadays, mostly without noticing this. When we are buying the groceries in the store, their identifiers are getting from barcodes. Its also the same with goods in the warehouses, postal parcels and so on. But not so many people actually know, how it works. What is 'inside' the barcode, and what is encoded on this image? Lets figure it out, and also lets write our own bar decoder. • ## On higher education, programmers and blue-collar job “Sometimes it happens that a man’s circle of horizon becomes smaller and smaller, and as the radius approaches zero it concentrates on one point. And then that becomes his point of view.” David Hilbert “When I thought I had hit rock bottom, someone knocked from below.” Stanisław Jerzy Lec ## Preface Does a programmer need a higher education? The flow of opinions on this undoubtedly urgent topic has not dried up, so I have decided to express my view. It seems to me the general disappointment in education is due to the numerous processes and changes in the profession and it needs serious study. Below I will discuss the most common misconceptions, myths, and underlying causes of the phenomenon. • ## Understanding the POCSAG paging protocol Long time ago, when a mobile phone costed about 2000$ and one minute of voice call was 50 cents, pagers were really popular. Later cellular phones became cheaper, calls and SMS prices became lower, and finally pagers mostly disappeared.

For people, who owned a pager before, and want to know how it works, this article will be useful.
• ## Teaching kids to program

• Translation

Hi. My name is Michael Kapelko. I've been developing software professionally for more than 10 years. Recent years were dedicated to iOS. I develop games and game development tools in my spare time.

Overview

Today I want to share my experience of teaching kids to program. I'm going to discuss the following topics:

• organization of the learning process
• learning plan
• memory game
• development tools
• lessons
• results and plans
• ## Starting point

For a point of reference in the economy for a long time understood «the Wealth of Nations» by Adam Smith. In modern science, this point was transformed into GDP — Gross Domestic Product.

On the other hand, the benchmark in monetarism (Milton Friedman) and the Austrian School of Economics (Ludwig Heinrich Edler von Mises, Friedrich August von Hayek) is freedom. Economic and political freedom.

The third fashionable point at present is the concept of “The Happy Planet Index”.

Thus, there is no single point of reference.

Nevertheless, this point is easy enough to detect if you understand the basic principles of building a modern post-industrial democratic society. If you understand what is common in these models. Where is their common starting point.

The modern economic system, as well as the modern democratic system, were not created for themselves. They are made for people. And that means not a person for the state, but a state for a person. Laws are not to limit human freedoms, but to ensure respect for the rights and freedoms of each person, laws to increase the happiness and wealth of a person. Not GDP, but the wealth of each individual.

States are made up of people. No people — no state. Poor people are a poor state.

Wealth, happiness, human freedom — is the area of respect for his rights.

Thus, a common unifying point in economic and political reasoning and theories is in the field of human rights.
• ## The Cake is a Lie

Have you ever thought — How to explain programming to the one never faced it before? It could be a problem, as long a new one will not understand you.

So, let's imagine — you have a friend, who is not soiled by computer science, never tried to automate something, never played factorio, never written a single line of code.

So, let's imagine a normal human being.

And let's call him Bill. He is not very good in Maths, just “not good”, but he loves candies!

Your task is to teach Bill some basic(or magic) IT things, you are doing every day. The simplest ones.
So what shall you do first? Basically — FEED HIM!

• ## $10 million in investments and Wozniak's praise — creating an educational computer for children We interviewed Mark Pavluykovskiy — the creator of the Piper educational computer. We asked him about immigrating from Ukraine to the US, how he almost died in Africa, graduated from Princeton, dropped out of a doctorate in Oxford and created a product that deserved a praise from Satia Nadella and Steve Wozniak. In mid-October the Sistema_VC venture capital fund hosted a conference called Machine Teaching, where creators of various educational startups assembled to talk about technical advancements. The special guest was Mark Pavluykosvkiy, the creator of Piper. His company created an educational computer — a children’s toy that, using wires, circuit boards and Minecraft teaches programming and engineering to children. A couple of years ago Mark completed a successful Kickstarter campaign, got a couple of Silicon Valley investors on board and raised around$11 million dollars in investments. Now he’s a member of Forbes’ “30 under 30” list, while his project is used by Satia Nadella and Steve Wozniak, among others.

Mark himself is a former Princeton and Oxford student. He was born in Ukraine, but moved to the US with his mother when he was a child. In various interviews Mark claimed that he doesn’t consider himself a genius, but simply someone who got very lucky. A lot of other people aren’t so lucky, however, and he considers it unfair. Driven by this notion, during his junior year he flew to Africa, where he almost died.
• ## Hello world! Or Habr in English, v1.0

This is the first post in our blog in 2019. And this is important for all of us: we are finally launching the English version of Habr! Actually it was ready in the middle of December, but — you know — releasing a new feature right before Christmas is like deploying on Friday afternoon. So we decided to do it in the beginning of 2019.