Railroad Street
Published 5 May 2023Whalebacks were a type of ship indigenous to the Great Lakes during the late 1890s and mid 1900s. They were invented by Captain Alexander McDougall, and revolutionized the way boats on the Great Lakes handled bulk commodities. Unfortunately, their unique design was one of the many factors which led to their discontinuation.
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August 11, 2023
The Weirdest Boats on the Great Lakes
March 14, 2023
May 29, 2021
Depression and suicide rates during the Wuhan Coronavirus pandemic
At Works in Progress, Scott Alexander looks at the details of rates of depression (which went up during the pandemic) and suicides (which surprisingly went down):
When COVID started spreading, life got more depressing, people became more depressed, but suicide rates went down. Why?
First, are we sure all of that is true? I won’t waste your time listing the evidence that life got more depressing, but what about the other two?
Ettman et al. conveniently had data from nationally representative surveys about how many Americans were depressed before COVID-19. They found another nationally representative sample and asked them the same questions in late March/early April 2020, when the first wave of US cases and lockdowns was at its peak. They found that 3 times as many people had at least one depression symptom, and 5–10x as many people scored in the range associated with “moderately severe” or “severe” depression.
This is a good study. It’s published in the Journal of the American Medical Association, a good journal. It’s been cited 50+ times in 6 months. Really the only thing anyone could have against it is the implausibly large effect it found. But it matches similar studies from Australia, Portugal, and around the world. Let’s say it’s real.
Along with the increased depression came an increase in people who said they were thinking about suicide. According to the US CDC, more than twice as many Americans considered suicide in spring 2020 compared to spring 2018 (10.7% vs. 4.3%).
Yet completed suicide rates stayed flat or declined. It’s hard to tell exactly which, because suicide is rare and noisy, and you need lots of data before anything starts looking statistically significant. But there are studies somewhere between “flat” and “declined” from Norway, England, Germany, Sweden, and New Zealand.
We also have two more complete reports from larger countries that help us see the pattern in more detail. First is Japan. Studies by Tanaka and Nomura broadly agree on a similar pattern — a slight decrease in suicides in the earliest stage of the pandemic (spring 2020) followed by a larger increase during the autumn. Here’s Nomura’s data:
The top graph is women, the bottom is men. The blue and red lines represent the 95% confidence range for an “average” year. Months that differ significantly from the average have little dots on top of their bars. You can see that April 2020 had significantly less suicide than average, among both genders, and July/August/September have more than average for women (and trend on the high side for men too).
Second is the US. The US Centers for Disease Control recently released their “nowcast” of 2020 deaths. These use the limited amount of data they have now to predict what the trends will look like once all the data comes in; their prediction process seems reasonable and we can probably treat the figures as canonical. Here’s their main result:
Suicide rates were pretty normal until March, when they dropped off pretty quickly and stayed low until midsummer. They’ve since hovered around normal again. Overall, suicides declined by 5.6%.
All these countries combine to form a picture of suicide rates dipping very slightly during the first and most frantic period of the pandemic — March to May — and then going back to normal (except in Japan, where things have since gotten worse). Thus the paradox: increasing depression combined with decreasing suicides. What’s going on?
May 23, 2021
QotD: The psychological impact of extended lockdowns
Claudio Grass (CG): A lot has been said and written about the economic and financial impact of the covid crisis and all the lockdowns and restrictions that came with it. However, the mental health implications haven’t really received the attention they arguably merit, at least not by mainstream media or government officials. Over the last year, we saw self-reported depression rates creep up in many Western nations, while excessive alcohol consumption and the abuse of prescription drugs also jumped. Do such trends raise concerns over longer-term problems or will we all simply snap back to normal once the crisis is over?
Theodore Dalrymple (TD): The first thing to say is that I do not like the term “mental health.” Was Isaac Newton mentally healthy, or Michelangelo? I think part of the problem is very concept of mental health. It implies that there is some state or condition of mind deviation from which is analogous to illness. Once this idea takes hold, it is clearly up to an expert to cure the person, or better still prevent him from getting ill in the first place. This expectation cannot be met, but the idea that it can be makes people more fragile.
Second, people clearly vary much in their response to confinements, lockdowns, closures of resorts of entertainment, etc. For myself, I have reached the age of misanthropy or self-sufficiency when these things make comparatively little difference to my life. I have plenty of space and plenty of things to do, in essence reading and writing. But that does not make me mentally healthier than a young man who is frustrated because he cannot play football with his friends and becomes ratty – moreover living in a very confined space.
Depression is so loosely defined a term that it has become almost valueless as a diagnosis. How often have you heard someone say “I’m unhappy” rather than “I’m depressed?” The semantic shift is very important. The proper response to someone who says that he is depressed is to give him antidepressants, even though these don’t work in the majority of cases, except as a placebo, and have potential side-effects. It is always tempting for people who are unhappy to drink alcohol – to drown their sorrows, as we say. Of course, if you drink too much, you might become really and truly depressed. A person who did not respond to the current situation with a little gloom would be odd.
Claudio Grass, “Theodore Dalrymple: Self-Control And Self-Respect Have Become Undervalued”, The Iconoclast, 2021-02-17.
March 3, 2021
Gen Z is suffering … but not enough?
In Quillette, Freya India considers the plight many of her cohort find themselves in during the ongoing efforts to combat the spread of the Wuhan Coronavirus (aka Covid-19):
My generation is miserable. Gen Z, those of us born after 1997, are the saddest, loneliest, and most mentally fragile age group to date, cursed with rising rates of anxiety, depression, and suicide. How can that be? How can a generation with everything feel so desperately unhappy? By almost every metric, human life is dramatically better today than it ever has been. The number of people living in extreme poverty has fallen from around 90 percent in 1820 to just 10 percent in 2015, while rates of illiteracy, mortality, and battle deaths are also in rapid decline. For the most part, Gen Z are heirs to an immense fortune: a utopian world of instant gratification and technological dynamism. In theory, this should be the age of happiness.
And yet, misery abounds. In the United States, 54 percent of Gen Z report anxiety and nervousness, according to researchers at the American Psychological Association. This is compared with only 40 percent of millennials and a national average of 34 percent. It isn’t just a case of self-report bias either, since the suicide rate for Americans aged between 15 and 24 has risen by over 51 percent in the last decade. For Gen Z women in particular, suicide rates have risen a staggering 87 percent since 2007. In my home country of the UK, one in four girls is clinically depressed by the time they are 14.
There’s no shortage of articles trying to make sense of the mental health epidemic at a time of such global prosperity. Teens and pre-teens today, we’re told, are simply interred beneath the weight of political issues like climate change, immigration, and sexual assault, as well as fatigued by job stress, exam burnout, and the attainment of unrealistic social media standards. The antidote, many suggest, lies in practicing better “self-care,” from daily gratitude journaling to adopting a 38-step skincare routine. And it’s a popular remedy. Since the pandemic began, online searches for “self-care” have risen 250 percent, with schools, universities, and employers turning to compulsory wellness programmes like mindfulness training and meditation sessions to improve mental health.
But, I suspect the problem is more nuanced than this. I don’t doubt that Gen Z is under a lot of strain, but I also think our plight is unique. For the first time in history, much of our misery stems not from too much suffering, but from not suffering enough. Gen Z does face real problems. I have certainly felt beleaguered by the pressures of social media, an oversaturated job market and the impact of coronavirus restrictions on my education. On top of that, there’s the difficulty of simply trying to exist as a fallible human in a political climate which demands infallibility, where nothing feels light-hearted anymore, and everything we say or do in our youth is stained onto the Internet for all time.
So, pressure is no doubt part of it. But previous generations faced egregiously difficult times: world wars, pandemics, economic crises, political rebellions, totalitarian regimes, and conditions of extreme poverty. Not only that, but today there are a wider range of mental health services available than ever before, and Gen Z are more likely than any other generation to seek treatment. So, for our rates of mental illness and suicide to be so high in a time of relative peace, there must exist a more convincing explanation than simply the asperities of life.
What lurks over my generation is not just a sense of misery, but meaninglessness. We exist in a state of lethargy and unfulfillment, tormented not by the tragedy of it all, but the futility. This is a point most articles and public figures today are less willing to discuss. But, to examine this possibility isn’t to say that Gen Z never struggle — but to suggest that at least some of us are caught in a rut of boredom, not burnout.
October 22, 2018
Looting – Pilates – Suicides Among Soldiers I OUT OF THE TRENCHES
The Great War
Published on 20 Oct 2018Crisis Call Center (US): http://crisiscallcenter.org/crisisser…
Crisis Service Canada: http://www.crisisservicescanada.ca/
Mind (UK): https://www.mind.org.uk/
Deutsche Depressionshilfe: https://www.deutsche-depressionshilfe…
May 3, 2018
QotD: Resisting the black dog
Last week I was having a bad day — nothing tragic, just adult life’s vicissitudes — when I got an email from a complete stranger that knocked me on my ass.
I’ll call this guy John. John recently survived a brush with suicidal depression and anxiety. John’s story is both terrifying and inspiring because he faced that depression without a job, without medical insurance, and (until he reached out for help) without a support network, and came out on the other end. John took a leap of hope, sought help from a loved one, got treatment, and got through the crisis. Is he happy all the time? I doubt it. Who is? But he’s managing the illness successfully and living his life.
John thanked me for writing openly about my experiences with severe depression and anxiety and how they have changed my life. He expressed a sentiment that I also experienced as a powerful deterrent to getting help: the fear that medication, or hospitalization, and therapy somehow mark you as other and lead to the end of your plans and ambitions forever. It’s not true. It helps, John said, to see other people who have fought mental illness, taken the plunge into serious treatment, and come out the other side continuing to pursue their careers and families and lives. John thanked me for writing, and said I made a difference for him and helped him imagine recovery as a possibility. I’m going to remember that on my worst days, when I’m down on myself.
People who have fought mental illness — people who are still struggling with it, every day — can change people’s lives by offering hope.
Depression and anxiety are doubly pernicious. They don’t just rob you of your ability to process life’s challenges. They rob you of the ability to imagine things getting better — they rob you of hope. When well-meaning people try to help, they often address the wrong problem. “Your relationship will work out if you just talk,” or “I’m sure your boss doesn’t actually hate you,” or “things will look up and you’ll find another job” may all be true, and may all be good advice. But they don’t address the heart of mental illness. A depressed or anxious person isn’t just burdened with life’s routine problems. They’re burdened with being unable to think about them without sheer misery, and being unable to conceive of an end to that misery continuing, endlessly, in response to one problem after another. Solving the problems, one by one, doesn’t solve the misery.
The hope you can offer to someone who is depressed or anxious isn’t your problems will all go away. They won’t. That’s ridiculous (though certainly it’s much easier to solve or avoid problems when you’re not debilitated). The hope you can offer is this: you will be able to face life’s challenges without fear and misery. The hope isn’t that your life will be perfect. The hope is that after a day facing problems you’ll still be able to experience happiness and contentment. The hope is that you’ll feel “normal” again.
Ken White, “Why Openness About Mental Illness is Worth The Effort And Discomfort”, Popehat, 2016-08-09.
November 14, 2017
QotD: Depressive writing leads to depressed readers
Agatha Christie gave her characters foibles, sure, and often there was a tight intrigue and not just the murderer but two or three other people would be no good. BUT the propensity of the characters gave you the impression of being good sort of people. Perhaps muddled, confused, or driven by circumstances to the less than honorable, but in general driven by principles of honor or love (even sometimes the murderer) and wanting to do the right thing for those they cared about.
You emerge from a Christie memory with the idea, sure, that of course there was unpleasantness, but most of the people are not horrors.
How did we get from there to now, where the characters aren’t even evil? They’re just dingy and grey and tainted, all of them equally. The victim, the detectives, the witnesses, will be vile and contorted, grotesque shapes walking in the world of men.
If this is a reflection of the psyches of most authors, I suddenly understand a lot about the self-hatred of western intellectuals.
But I wonder if it’s a fashion absorbed and perpetuated, communicated like the flu, a low grade dingy patina of … not even evil, just discontent and depression and a feeling that everyone in the world is similarly tainted.
I realized that was part of what was depressing me, partly because I’m a depressive, so I monitor my mood fairly regularly. BUT what about normal people? What if they just absorb this world view — and the idea that it’s smart and sophisticated, too — through popular entertainment, through movies and books and shows and then spew it out into the world, because it stands like a veil between them and reality, changing the way they perceive everything.
[…] such despairing stuff, such low grade despair and unpleasantness change us, particularly when they’re unremitting. You internalize these thoughts, they become part of you. If humanity is a plague, who will have children? If humanity is a plague, why not encourage the criminals and terrorists? If humanity is a plague who is clean?
You. Me. Most human beings. Oh, sure, we’re not perfect — I often think people who write this lack the ability to distinguish between not being perfect and being corrupt and evil — and we often have unlovely characteristics. But, with very few exceptions, most people I know TRY to be decent by their lights, try to raise their kids, help their friends and generally leave the world a little better.
Now, are we representative of everyone? Of course not. A lot of people are raised in cultures (here and abroad) that simply don’t give their best selves a chance. But why enshrine those people and not the vast majority who are decent and well… human?
Even in a mystery there should be innocent and well-intentioned people. It gives contrast to the darker and more evil people and events.
Painting only in dark tints is no more accurate than painting only in pale tints. It doesn’t denote greater artistry. It just hangs a grey, blotched veil between your reader and reality, a veil that hides what is worthwhile in humans and events.
Make yourself aware of the veil and remove it. It’s time the low-grade depression of western civilization were defeated. No, it’s not perfect, but with all its failings it has secured the most benefits to the greatest number of people in the long and convoluted history of mankind. Self-criticism might be appropriate, but not to the exclusion of everything else.
Say no to the dingy-grey-patina. Wash your eyes and look at the world anew. And then paint in all the tints not just grey or black.
Sarah Hoyt, “A Dingy Patina”, According To Hoyt, 2015-10-22.
April 26, 2017
The End of Play: Why Kids Need Unstructured Time
Published on 25 Apr 2017
“School has become an abnormal setting for children,” says Peter Gray, a professor of psychology at Boston College. “Instead of admitting that, we say the children are abnormal.”
Boston College Psychology Professor Peter Gray says that a cultural shift towards a more interventionist approach to child rearing is having dire consequences for the well-being of kids. “Over the same period of time that there has been a gradual decline in play,” he told Reason‘s Nick Gillespie, “there are well documented, gradual, but ultimately huge increases in a variety of mental disorders in childhood — especially depression and anxiety.”
Gray believes that social media is one saving grace. “[Kids] can’t get together in the real world…[without] adult supervisors,” he says, “but they can online.”
For more on Gray’s work, follow his blog at Psychology Today.
Edited by Mark McDaniel. Cameras by Todd Krainin and Jim Epstein. Music by Broke for Free.
October 8, 2016
QotD: Depression
The book [In the Jaws of the Black Dogs, (1999)] is a compelling, unpleasant read, valuable because it tells us three things. First, that such depressions do not yield to shrink fixes, and will not otherwise “go away.” Second, that there is no “template,” for each sufferer is his own constellation of symptoms which no outsider is privileged to explore. And thus, third, the depression can be controlled and mastered, only if one grasps these things. One must, as it were, leash one’s own black dogs, and it will be neither easy nor painless. While perhaps overwritten, the book is admirable for containing no victim’s plaint, no false appeal for applause, and absolutely no pop psychology.
David Warren, “Unfinished conversations”, Essays in Idleness, 2016-09-19.
June 10, 2016
A breakthrough in our understanding of the causes of depression
Scott Alexander takes a quick look at a recent discovery in medication for depression:
A few weeks ago, Nature published a bombshell study showing that ketamine’s antidepressant effects were actually caused by a metabolite, 2S,6S;2R,6R-hydroxynorketamine (don’t worry about the name; within ten years it’ll be called JOYVIVA™®© and you’ll catch yourself humming advertising jingles about it in the shower). Unlike ketamine, which is addictive and produces scary dissociative experiences, the metabolite is pretty safe. This is a big deal clinically, because it makes it easier and safer to prescribe to depressed people.
It’s also a big deal scientifically. Ketamine is a strong NMDA receptor antagonist; the metabolite is an AMPA agonist – they have different mechanisms of action. Knowing the real story behind why ketamine works will hopefully speed efforts to understand the nature of depression.
But I’m also interested in it from another angle. For the last ten years, everyone has been excited about ketamine. In a field that gets mocked for not having any really useful clinical discoveries in the last thirty years, ketamine was proof that progress was possible. It was the Exciting New Thing that everybody wanted to do research about.
Given the whole replication crisis thing, I wondered. You’ve got a community of people who think that NMDA antagonism and dissociation are somehow related to depression. If the latest study is true, all that was false. This is good; science is supposed to be self-correcting. But what about before it self-corrected? Did researchers virtuously say “I know the paradigm says NMDA is essential to depression, and nobody’s come up with a better idea yet, but there are some troubling inconsistencies in that picture”? Or did they tinker with their studies until they got the results they expected, then triumphantly declare that they had confirmed the dominant paradigm was right about everything all along?
February 7, 2015
Is there a relationship between physical illness and depression?
Last month, Scott Alexander tried to show the evidence, pro and con, on whether we have detected a causal relationship between physical ailments and depression:
Start with From inflammation to sickness and depression [PDF], Dantzer et al (2008), who note that being sick makes you feel lousy [citation needed]. Drawing upon evolutionary psychology, they theorize this is an adaptive response to make sick people stay in bed (or cave, or wherever) so the body can focus all of its energy on healing. A lot of sickness behavior – being tired, not wanting to do anything, not eating, not wanting to hang around other people – seems kind of like mini-depression.
All of this stuff is regulated by chemicals called cytokines, which are released by immune cells that have noticed an injury or infection or something. They are often compared to a body-wide “red alert” sending the message “sickness detected, everyone to battle stations”. This response is closely linked to the idea of “inflammation”, the classic example of which is the locally infected area that has turned red and puffy. Most inflammatory cytokines handle the immune response directly, but a few of them – especially interleukin-1B and tumor necrosis factor alpha – cause this depression-like sickness behavior.
[…]
Here are some other suspicious facts about depression and inflammation:
– Exercise, good diet and sleep reduce inflammation; they also help depression.
– Stress increases inflammation and is a known trigger for depression.
– Rates of depression are increasing over time, with the condition seemingly very rare in pre-modern non-Westernized societies. This is commonly attributed to the atomization and hectic pace of modern life. But levels of inflammation are also increasing over time, probably because we have a terrible diet that disrupts the gut microbiota that are supposed to be symbioting with the immune system. Could this be another one of the things we think are social that turn out to be biological?
– SSRI antidepressants, like most medications, have about five zillion effects. One of the effects is to reduce the level of inflammatory cytokines in the body. Is it possible that this is why they work, and all of this stuff about serotonin receptors in the brain is a gigantic red herring?
– It’s always been a very curious piece of trivia that treating depression comorbid with heart disease significantly decreases your chances of dying from the heart disease. People just sort of nod their heads and say “You know, mind-body connection”. But inflammation is known to be implicated in cardiovascular disease. If treating depression is a form of lowering inflammation, this would make perfect sense.
– Rates of depression are much higher in sick people. Cancer patients are especially famous for this. No one gets too surprised here, because having cancer is hella depressing. But it’s always been interesting (to me at least) that as far as we can tell, antidepressants treat cancer-induced depression just as well as any other type. Are antidepressants just that good? Or is the link between cancer being sad and cancer causing depression only part of the story, with the other part being that the body’s immune response to cancer causes inflammatory cytokine release, which antidepressants can help manage?
– Along with cancer, depression is common in many other less immediately emotion-provoking illnesses like rheumatoid arthritis and diabetes. The common thread among these illnesses is inflammation.
– Inflammation changes the activity level of the enzyme indoleamine 2,3 dioxygenase. This enzyme produces kynurenines which interact with the NMDA receptor, a neurotransmitter receptor implicated in depression and various other psychiatric diseases (in case your first question upon learning about this pathway is the same as mine: yes, kynurenines got their name because they were first found in dog urine).
– Sometimes doctors treat diseases like hepatitis by injecting artificial cytokines to make the immune system realize the threat and ramp up into action. Cytokine administration treatments very commonly cause depression as a side effect. This depression can be treated with standard antidepressants.
– Also, it turns out we can just check and people with depression have more cytokines.
There’s also some evidence against the theory. People with depression have more cytokines, but it’s one of those wishy-washy “Well, if you get a large enough sample size, you’ll see a trend” style relationships, rather than “this one weird trick lets you infallibly produce depression”.
[…]
So in conclusion, I think the inflammatory hypothesis of depression is very likely part of the picture. Whether it’s the main part of the picture or just somewhere in the background remains to be seen, but for now it looks encouraging. Anti-inflammatory drugs do seem to treat depression, which is a point in the theory’s favor, but right now the only one that has strong evidence behind it has side effects that make it undesirable for most people. There’s a lot of room to hope that in the future researchers will learn more about exactly how this cytokine thing works and be able to design antidepressant drugs that target the appropriate cytokines directly. Until then, your best bets are the anti-inflammatory mainstays: good diet, good sleep, plenty of exercise, low stress levels, and all the other things we already know work.
December 1, 2013
QotD: The psychological profile of a losing team’s fans
One of the joys of living in New York City is that a psychoanalyst is never too far away. Indeed, my neighbor Barry Stern is a professor of medical psychology at Columbia University College. After I had explained my predicament, he quipped, “I think New York Mets fans would have a lot to say about this,” before launching into a psychoanalytical explanation in which “masochists” (his word) “turn passive into active” when faced by a traumatic experience over which they have no control.
“It sounds like you take control of the experience of disappointment by preemptively becoming disappointed,” he told me. “You savor the anticipated loss when the team is down, a stance from which you can comfortably root for a win, without risking too much.” Viewed like that, the 1-0 lead is inherently less pleasurable.”Rather than enjoying your team being ahead, you manage the anxiety associated with them inevitably mucking up, negating the positive mood created through their lead … by spoiling it yourself. No more anxiety, just depression, and the familiar feeling of managing the weak sense of hope they might just pull this one out.”
Roger Bennett, “Is there such a thing as a happy football fan?”, ESPN Relegation Zone, 2013-09-17
June 23, 2012
The real ending to Krugman’s favourite example, the Capitol Hill babysitting co-op
Tim Harford recounts the tale of the Capitol Hill babysitting co-op, which Paul Krugman is very fond of using as an example to support his economic prescriptions, but he includes the part that Krugman tends to ignore … the ending:
One of the most renowned parables in economics is that of the Capitol Hill babysitting co-operative. It became famous because of Paul Krugman, a winner of the Nobel memorial prize in economics and a pugnacious columnist for The New York Times.
Long, long ago (the 1970s) in a town far, far away (Washington, DC) there was a babysitting co-op with a problem. The 150 or so families in the co-op, mostly congressional staffers, shared babysitting duties and kept track of who was owed babysitting, and who was owing, with a system of “scrip” – tokens good for a half-hour’s sitting.
Thanks to an administrative misstep, the co-op ended up short of tokens. Most families wanted more, as a buffer in case they had a run of social engagements, and so most families wanted to stay in and sit for others. Of course, if everyone wants to babysit, nobody goes out, and that means nobody babysits either. The co-op suffered a demand-led depression: there was no shortage of people willing to supply babysitting services, but because of a failure of monetary policy, this potential supply was not called into play. [. . .]
Two-and-a-half cheers, then, for Krugman. But something has been nagging at me ever since I read the original story of the Capitol Hill babysitting co-op, published in 1977 by Joan and Richard Sweeney. Paul Krugman’s most recent retelling does not mention how the original story ends: the co-op prints too much scrip, inflationary pressures spring up and are suppressed, and the co-op seizes up again because nobody wants to stay at home babysitting. Krugman is right when he says that economies sometimes suffer from problems that have technical solutions. Perhaps he is too quick to suggest that those technical solutions are simple.
But let me look for compromise. The babysitting co-op was ruined because it was run, incompetently, by a bunch of Capitol Hill lawyers. In this respect I think we can all agree that it remains an important cautionary tale.
January 16, 2012
It may be pseudoscientific gibberish, but it makes a good newspaper headline
It’s pretty much a certainty that your local newspaper and radio stations have been busy pushing the meme that today is “Blue Monday“. It’s actually a bit of advertising creativity that’s metastasized:
January is a depressing time for many. The weather’s awful, you get less daylight than a stunted dandelion and your body is struggling to cope with the withdrawal of the depression-alleviating calorific foods, such as chocolate, of the hedonistic festive period. January is one long post-Christmas hangover.
So there are many reasons why someone may feel particularly “down” during January. But every year, much of the media become fixated on a specific day — the third Monday in January — as the most depressing of the year. It has become known as Blue Monday.
This silly claim comes from a ludicrous equation that calculates “debt”, “motivation”, “weather”, “need to take action” and other arbitrary variables that are impossible to quantify and largely incompatible.
True clinical depression (as opposed to a post-Christmas slump) is a far more complex condition that is affected by many factors, chronic and temporary, internal and external. What is extremely unlikely (i.e. impossible) is that there is a reliable set of external factors that cause depression in an entire population at the same time every year.
But that doesn’t stop the equation from popping up every year. Its creator, Dr Cliff Arnall, devised it for a travel firm. He has since admitted that it is meaningless (without actually saying it’s wrong).