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Well, bad news travels fast. Over the last couple of weeks I’ve been receiving a couple of emails regarding B3’s decision of shutting down its ftp site. More specifically, users are eager to know how it will impact my data grabbing packages in CRAN. I’ll use this post to explain the situation for everyone. The only package affected directly will be GetHFData, which uses the ftp site for downloading the raw zipped files with trades and quotes. The main function will no longer work as all internet files are not available.

One of the investment concepts that every long term investor should know is the effect of consistency over corporate performance. The main idea is that older and profitable companies are likely to continue to be profitable and even improve its performance in the upcoming years. Likewise, companies with constant losses are likely to continue in the same path. This idea is related to the Lindy Effect. Quoting directly from wikipedia: The Lindy effect is a theory that the future life expectancy of some non-perishable things like a technology or an idea is proportional to their current age, so that every additional period of survival implies a longer remaining life expectancy.

I’m using R for at least five years and always been curious about its usage in Brazil. I see some minor personal evidence that the number of users is increasing over time. My book in portuguese is steadily increasing its sales, and I’ve been receiving far more emails about my R packages. Conference are also booming. Every year there are at least two or three R conferences in Brazil. What I learned from experience is that software choice is a group decision. It is very likely that you will use whatever your peer group uses.

One of the subjects that I teach in my undergraduate finance class is the relationship between risk and expected returns. In short, the riskier the investment, more returns should be expected by the investor. It is not a difficult argument to make. All that you need to understand is to remember that people are not naive in financial markets. Whenever they make a big gamble, the rewards should also be large. Rational investors, on theory, would not invest in risky stocks that are likelly to yield low returns.

The Central Bank of Brazil (BCB) offers access to the SGS system (sistema gerenciador de series temporais) with a official API available here. Over time, I find myself using more and more of the available datasets in my regular research and studies. Last weekend I decided to write my own API package that would make my life (and others) a lot easier. Package GetBCBData can fetch data efficiently and rapidly: Use of a caching system with package memoise to speed up repeated requests of data; Users can utilize all cores of the machine (parallel computing) when fetching a large batch of time series; Allows the choice for format output: long (row oriented, tidy data) or wide (column oriented) Error handling internally.

BatchGetSymbols is my most downloaded package by any count. Computation time, however, has always been an issue. While downloading data for 10 or less stocks is fine, doing it for a large ammount of tickers, say the SP500 composition, gets very boring. I’m glad to report that time is no longer an issue. Today I implemented a parallel option for BatchGetSymbols. If you have a high number of cores in your computer, you can seriously speep up the importation process. Importing SP500 compositition, over 500 stocks, is a breeze.

In the last few weeks we’ve seen a great deal of controversy in Brazil regarding financial investments. Too keep it short, Empiricus, an ad-based company that massively sells online courses and subscriptions, posted a YouTube ad where a young girl, Bettina, says the following: Hi, I'm Bettina, I am 22 years old and, starting with R$ 1,500, I now own R$ 1,042,000 of accumulated wealth. She later explains that she earned the money by investing in the stock market over three years. For my international audience, the proposed investment is equivalent of turning 394 dolars into 263169.

I received many messages regarding my book promotion (see previous post ). I’ll use this post to answer the most frequent questions:  Does the paperback edition have a discount? No. The price drop is only valid for the ebook edition but not by choice. Unfortunately, Amazon does not let me do countdown promotions for the paperback edition. So, in favor of those, like myself, that like the smell of a fresh book page, I manually dropped the price of the paperback to 17.99 USD (it was 24.99 USD).

I recently did a book promotion for my R book in portuguese and it was a big sucess! My english book is now being sold with the same promotion. You can purchase it with a 50% discount if you buy it on the 10th day of march. See it here. The discount will be valid throughout the week, with daily price increases. If you want to learn more about R and its use in Finance and Economics, this book is a great opportunity. You can find more details about the book, including datasets, R code and all that good stuff here.

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