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A rising tide sinks all boats… eventually

A rising tide sinks all boats… eventually

Have you heard that ice cream causes murder or that global warming has led to an increase in piracy? Apparently in Maine, consuming more margarine leads to more divorces, while increased US spending on science, space and technology results in increases in suicides by hanging, strangulation and suffocation.  Actually, these are examples of spurious or false correlations – entirely unrelated things whose data appear to suggest a causal relationship.  And in these examples, the outcome is little more damaging than a few humorous media articles and a couple of books.

False correlations, however, run deep.  And some can have a pernicious impact on large numbers of us.  Consider for example, the well-worn neoliberal saying that “a rising tide raises all boats.”  It is based on two mistaken premises.  First, that employment is always a route from poverty to prosperity; and second, that an increase in overall employment must benefit everyone.  And it is for these reasons that continued economic growth is the altar upon which all else must be sacrificed.

The evidence for the benefits of economic growth for all is far more nuanced.  In pre-industrial economies where most people worked the land, there is little evidence that much growth occurred beyond that allowed by the ups and downs of the annual harvest.  Indeed, it took the economies of the British Isles until the eighteenth century to re-reach the technological level of the Roman Empire; so what economic growth their had been amounted to a catching up following a major economic collapse.  And even during that period of lethargic growth, various plagues and famines – including the catastrophic Black Death in the fourteenth century – rapidly threw economies into reverse.

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Garden Logic – understanding correlation and causation in our gardens and landscapes

Garden Logic – understanding correlation and causation in our gardens and landscapes

This home landscape is managed using science-based methods; the only routine additions are water and arborist chip mulches.

Upon reading this post’s title, you may be inclined to stop right there. (That’s why I have an eye-catching photo to lure you in.) While logic may seem irrelevant to your enjoyment of gardening, I can guarantee that reading this blog post will challenge many seemingly logical assumptions you’ve heard or read about. Recognizing unsubstantiated assumptions and avoiding their pitfalls means you can make wise choices about how you care for your gardens and landscapes.

You can find this and thousands of other silly correlations at www.tylervigen.com

A few definitions are needed before we get started:

Correlation refers to variables whose changes mirror one another. For instance, the addition of nitrogen fertilizer to container plants is correlated to plant growth: as nitrogen levels increase so does plant growth. You can also have inverse correlation, where the variables move in opposite directions. An example is water availability in soil and planting density: the more plants you have in a specified area, the less water is in the soil.

Plant growth is correlated with increased nitrogen and other nutrients (from Xu et al. 2020)

Causation takes correlation one step further: it establishes that one of those variables is causing the change in the other. Using the same examples, we know through published evidence that the increase in nitrogen is causing the increase in plant growth, and the increase in planting density is causing the decrease in soil water because of competing roots. These relationships are obvious to us, but what’s important is that these causative effects have been established through scientific experiments.

Inverse relationship between planting density and soil water content (from Shao et al. 2018)          

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Evictions, tenants and the fragility of a “correlated” world

Evictions, tenants and the fragility of a “correlated” world

As eviction moratoriums around the United States come to an end, it is expected that landlords will begin evicting nonpaying tenants en masse. Eviction by itself is an unremarkable phenomenon in America. Some 900,000 per year have been occurring routinely in the last several years affecting about 2.3 million people annually.

The scale this time is different. No one knows exactly how things will play out in the United States (or elsewhere for that matter). But, barring new moratoriums on eviction one estimate suggests 23 million people will be subject to eviction by the end of September, more than 10 times the number for an entire year.

Where all those households would go is a puzzling question as the limited space in facilities for the homeless could never hold them. And, given the continuing coronavirus pandemic, those facilities that are observing proper social distancing have had to limit their capacity.

Perhaps the U.S. Congress will come to its senses and pass aid for renters just as it has done for businesses. I am doubtful about such prospects.

But, I am also interested in another important question: Who will replace evicted tenants? Here the problem of correlation looms large. Generally speaking, landlords don’t worry too much if Joe in apartment 238 and Sally in apartment 424 both lose their jobs. Their job losses are usually related to their specific circumstances, a company moving its operations or a firing due to poor performance. These losses are uncorrelated to the situations of other tenants. There will therefore be paying tenants to take the place of Joe and Sally should the landlord have to evict them.

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The Collapse Of This Historic Correlation Suggests A Major Crisis Is Imminent

The Collapse Of This Historic Correlation Suggests A Major Crisis Is Imminent

A lot of digital ink has been spilled in recent days over the perplexing reversal of the Yen, which for years was seen by the market as a “flight to safety” trade (as unexpected crisis events would prompt capital repatriation into Japan or so the traditional explanation went), only to suffer a major selloff in the past week as it suddenly started trading not as a funding currency for risk-on FX pairs, but as a risk asset itself.

To us, the reversal is far less perplexing than some smart people make it out to be: with Japan now effectively in a recession following the catastrophic Q4 GDP print which crashed 6.3% annualized, validated by today’s just as terrible PMI report…

.. and with Japan now set to suffer a major hit due to the coronavirus epidemic spreading like wildfire across the region, it is only a matter of time before the BOJ follows the ECB and Fed in reversing what has been years of QE tapering, and either cuts rates further into negative territory or expands its QQE (with yield control), and starts buying equities (although with the central bank already owning more than 80% of all ETFs, one wonders just what risk assets are left for the central bank to buy). Needless to say, both of these would have an adverse impact on the yen, and potentially lead to destabilization in the Japanese bond market which for years has defied doom-sayers, but it will only take one crack in the BOJ’s confidence for Japan’s entire house of cards to fall apart. That said, we are not there quite yet.

Furthermore, after the bizarre move in the prior two days, overnight the JPY appears to regain some normalcy, when it traded as it should (i.e., it was once again a risk-off proxy), with the USDJPY sliding during the two major “risk-off” events overnight.

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Wedges and Triangles: Big Move Ahead?

Wedges and Triangles: Big Move Ahead? 

The central bank high is euphoric, the crash and burn equally epic.

Just out of curiosity, I called up a few charts of key markets: stocks (the S&P 500), volatility (VIX), gold and the U.S. dollar (UUP, an exchange-traded fund for the dollar). Interestingly, all of these charts displayed some version of a wedge/triangle.

In a wedge/triangle (a formation with many variations such as pennants), price traces out a pattern of higher lows and lower highs, compressing price action into the apex of a triangle as buyers and sellers reach an increasingly unstable equilibrium.

As price gets squeezed into a narrowing band, the likelihood increases that price will break out of the triangle, either up or down, in a major move.

So which way will these markets break–up or down? One thing is fairly certain: the S&P 500 (SPX) and the VIX (volatility) are on a see-saw–both don’t soar at the same time. If the VIX soars, stocks are plummeting as fear takes hold. If the VIX stumbles along the bottom of its range, market players are complacent and stocks loft higher.

Many observers see the same inverse relationship in gold and the U.S. dollar–when one is going up, the other is weakening.

I tested this widely accepted truism by aligning the charts of both the U.S. dollar and gold, and found that there were lengthy periods during which gold and the U.S. dollar rose in tandem: About That Supposed Correlation of the U.S. Dollar and Gold…. (July 8, 2013)

My conclusion: each is influenced by a number of factors, some shared, some unique to each asset. As a result of this complex confluence, at times both go up together and at times there is a negative correlation (see-saw effect), and during other periods, there is little correlation, i.e. they act entirely independent of the other.

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