Multilateral price indexes are often used to measure the evolution of prices over time when there are large volumes of transaction data, such as retail scanner data or housing data. The main challenge with computing multilateral indexes with large amounts of data is that these indexes often depend on a matrix where the dimensions are at least as large as the number of products.
That the arithmetic mean of a set of number is larger than the geometric mean is a foundational result in the theory of inequalities. This is a useful result for index numbers in particular as it gives that, for the same data, an index based on an arithmetic mean will always be larger than the corresponding index based on the geometric mean.
Comparing housing prices over time is difficult because of all the heterogeneity in housing that can both affect prices and vary over time. The typical solution to this problem is to use a hedonic price index that attempts to model the relationship between housing characteristics and price, and uses this to control the change in these characteristics over time.
Your browser does not support the audio tag. Download: PDF | EPUB | MP3 | WATCH VIDEO According to a simple linear trend, losses per disaster are down by about 80% since 1980, as a proportion of GDP. — Roger Pielke Jr. In the world of scientific disinformation, Roger Pielke Jr. is a well known player.
What causes inflation in prices over time? Increases in the money supply, of course. Although there are many reasons for increasing prices over time, money supply is one of the few things that can do so and grow without bound. Case closed, right? Not quite. In practice we can’t perfectly observe how prices change over time and instead we must measure inflation with an index number.
A diversity index is a way to measure the prevalence species in an ecosystem. Although these arise naturally in ecology, diversity indexes show up elsewhere as well.
Your browser does not support the audio tag. Download: PDF | EPUB | MP3 | WATCH VIDEO All models are wrong; the practical question is how wrong do they have to be to not be useful. — George Box In science, there’s an inherent trade off between comprehensibility and realism. Realistic models tend to be intricate … even convoluted. But to be comprehensible, a model must be simple.
Your browser does not support the audio tag. Download: PDF | EPUB | MP3 | WATCH VIDEO What had come to an end was not history itself, but an empire, whose time had run out. — Karl Schlögel in The Soviet Century In my last post, ‘The Half Life of Empire’, I charted the rise and fall of the British and US empires, as measured by their share of world energy use.
Your browser does not support the audio tag. Download: PDF | EPUB | MP3 | WATCH VIDEO Men make their own history, but they do not make it as they please. — Karl Marx, 1852 A good way to think about human history is that it has two distinct scales. On the small scale we have the churn of daily events — the stuff of endless individual exploits.
Introdução A falência de uma instituição financeira não é, em geral, o produto de um único erro ou de uma circunstância isolada. Trata-se, quase sempre, do acúmulo dinâmico de vulnerabilidades, decisões arriscadas e pressões contextuais que se inter-relacionam ao longo do tempo. No caso do Banco Master, a liquidação extrajudicial anunciada em 2024 não pode ser explicada por um fator único.
Your browser does not support the audio tag. Download: PDF | EPUB | MP3 | WATCH VIDEO To see what is in front of one’s nose needs a constant struggle. — George Orwell For decades, the word ‘fascist’ existed solely as a hyperbole — a term meant to insult rather than describe. But lately, politics have grown so hyperbolic that the label looks increasingly sincere.