This is my real-time unedited (just formatting cleanup) comments on an "original research article" in Frontiers in Systems Neuroscience, "Valproate reopens critical-period learning of absolute pitch".

anonymous-1 wrote:

study says drug can help learn perfect pitch:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3848041/pdf/fnsys-07-00102.pdf

they claim it's double blind, but doesn't someone being able to do something he otherwise couldn't (they claim) tell him which group he's in and therefore unblind it?

> On days 8–14 of each treatment, we instructed participants to undergo an on-line training program for approximately 10 min per day. During each online training session, they observed a video, which trained associations between piano tones and proper names.

so it could actually be a drug for better boring video watching focus?

oh god they put ppl thru a bunch of junk tests to try to control for mood, depression, mania, being smart

> We counted a training session as complete if the subject both watched the full length of the video (up to within 15 s of the end) and answered the subsequent test question correctly.

did they decide those rules before they started?

> There was no significant correlation between the number of completed training sessions and performance

hahaha

> The experiment was double-blind, as neither participants, nor experimenters knew the randomization for treatment conditions. However, we did ask participants to intuit in which arm they received VPA treatment, and why they thought so. We also instructed them to write down any side effects they experienced during the experiment. Out of the 18 participants who completed the second treatment arm, 17 guessed correctly.

hahaha i told you it wasn't blind

fucking liars

they found out during the study it was not blind

then publish it as a blind study

what scumbags

i think the prior study asserting the critical period exists at all might be more interesting. at least if it's any good. b/c i find a critical period a bit intuitively surprising. like i wouldn't rly expect it

> Second, the analysis of the crossover, i.e., of the 17 participants for whom we have data from both arms, revealed an order-dependent effect of treatment. For participants who took VPA first, AP performance was significantly higher after VPA treatment than after placebo. In contrast, for participants who initially took placebo, there was no such difference. It may be that carry-over effects impeded performance on the AP task in the second treatment arm.

that's odd

> Relatedly, it needs to be noted that we did not test how long the effect of the improvement in AP perception lasted.

so they did not study learning perfect pitch. they studied doing better on certain tests while actively on drugs, but not any kind of longer term skill improvement. so the study title:

> Valproate reopens critical-period learning of absolute pitch

that's bullshit. they didn't study that.

> In sum, our study is the first to show a change in AP with any kind of drug treatment. The finding that VPA can restore plasticity in a fundamental perceptual system in adulthood provides compelling evidence that one of the modes of action for VPA in psychiatric treatment may be to facilitate reorganization and rewiring of otherwise firmly established pathways in the brain and its epigenome (Shen et al., 2008).

wow such bullshit

like it's bad enough they are claiming it creates plasticity for pitch stuff – maybe it just makes u better at pitch without plasticity? among other things – but then to start saying they found out about psychiatry... ugh
the big picture tho is this is explanationless "science". they don't know what VPA does or how it works, and they are focusing on correlations (btwn taking VPA and high scores on pitch tests) not explanations

> If confirmed by future replications, our study will provide a behavioral paradigm for the assessment of the potential of psychiatric drugs to induce plasticity. In particular, the AP task may be useful as a behavioral correlate. If further studies continue to reveal specificity of VPA to the AP task (or to tasks on which training or intervention is provided), critical information will have been garnered concerning when systemic drug treatments may safely be used to reopen neural plasticity in a specific, targeted way.

i think they are saying here that they have no idea if VPA (their drug) has anything to do with pitch, or just helps learning more generally

the intended use for approving psychiatry drugs is disturbing

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Refuting the study like this took under 20 minutes. Then people discussed the point about whether the study was blind:

anonymous-1:
    How does that make it not double-blind?
curi:
    if you know what group you're in, that isn't blind.
    do you know what blind means? *confused*
anonymous-1:
    but you don't know, you guess
curi:
    they could tell which they were in
anonymous-1:
    they guessed which they were in
curi:
    so you think 17 out of 18 got it right by coincidence, and there was no unblinding information?
anonymous-1:
    still blind?
    they weren't told until after the study
    this is a standard thing in psych studies to find out whether the person can guess about placebo?
curi:
    if you can guess better than chance, then you have information about which group you're in (or ESP). that information means it's not fully blind. in this case they appear to have quite a lot of such info.
    "standard thing in psych studies" is not reassuring!!!
Justin Mallone:
    ya lol
    psych studies typically trash
anonymous-1:
    not by coincidence, by stuff like feeling the drug
curi:
    right, that makes it not blind.
anonymous-1:
    so yes no unblinding info
curi:
    feeling it is unblinding info
anonymous-1:
    you don't know for sure though
    hmmm
    why should that be considered unblinding?
curi:
    but if you know (from feeling it) better than chance, you know something about whether you have the placebo or not. you have information about it (just not PERFECT information if you don't know for SURE). so it's not fully blind. (and, again, they seem to in this case have had LOTS of info, so not close to blind)
Justin Mallone:
    doing double blind can be hard
curi:
    yeah in medical studies they sometimes use complex active placebos to try to make stuff blind
Justin Mallone:
    the fact that lots of stuff is done incompetently doesn’t lower the bar tho
curi:
    like try to find stuff that'll have the same side effects and other feelable consequences
anonymous-1:
    oh cool @ complex active placebos
    didn't know about that. makes sense

This is an essay I wrote in Feb 2002 criticizing marriage. Oh God, the writing style is so bad! I hope this will show you that no one is a lost cause!

I bet some of you FI bros are already better writers than this... So things are looking good for you!

I do like the use of italics and the connections between Shakespeare's play and my points. But lots of this is a mess, and it's got tons of that awful school essay style.

Can anyone refute some of these arguments? Reply in the comments below!

Marriage in Measure for Measure: A Destructive Force Revealed

The depth of Shakespeare's commitment to marriage is shown by the fact that he continues to take it for granted as an institution even while the action of his play, Measure for Measure, systematically reveals its ability to hurt people. Marriage even leads a number of characters to immoral ideas! The characters in the play seem to think marriage is very important, but at the same time they are constantly pointing out flaws. Their inability to notice the flaws they elucidate strongly supports the thesis. Hence, some of their statements will be highlighted, and the flaws examined.

In most societies, ideas about love and marriage do terrible damage. Marriage is a form of vertical, or contractual, relationship that functions as a control mechanism. Horizontal visions of marriage, in essence marriage as a true friendship or ARR (Autonomy Respecting Relationship), could utterly destroy the tradition. The more ARRs catch on, the more people would realise that no personal relationship needs contractual obligations, or state approval. This would lead to a more dynamic society, and even while the ideas are on the whole unpopular, some people would certainly begin to question their local dictator. Therefore, said tyrant cannot allow this process to begin; relationships must be painful obligations without truth-seeking. However, it must be noted that the ruler does not consciously understand this. He, too, acts on anti-rational memes which contain knowledge about what he must do. Some of them tell him to protect marriage. He does not know why he does this; there is no conspiracy. In Measure for Measure, the Duke goes to elaborate lengths to create a number of marriages, and enforce the contractual obligations inherent in them.

One of the issues Shakespeare goes into is distorted ethics; marriage contributes fairly well to confusing people ethically. For example, Isabella would choose highly immoral actions such as allowing her close friend and brother Claudio to die, before she would violate the rigid rules outlawing premarital sex. Any good person would make a minor, inconsequential sacrifice of some temporary discomfort to save the life of a valued friend. However, Isabella says, “I had rather my brother die by the law than my son should be unlawfully born” (Measure for Measure, Act III, Scene I, Lines 187-189). Isabella makes the same mistake as many others in her society, placing false importance on marital contracts. She cannot see the inherent harm, even when it hits her in the face by forcing her to sacrifice her brother. And, transitively, Shakespeare also misses the harm, or he would abandon marriage.

One of the issues Shakespeare goes into is reason; marriage causes people to act unreasonably. It is common to hear such lines as You will find true love someday or Your soulmate is out there, somewhere, waiting. The message is to cheer up, because the listener will find love. This is a self-fulfilling prophecy. In most people, such a strong desire for love is instilled, that they will often convince themselves a relationship is love, despite reality. They then hang on to this so-called “love” for fear of losing their soulmate. For example, the Duke says of Marianna, “[Angelo’s] unjust unkindness, that in all reason should have quenched her love, hath, like an impediment in the current, made it more violent and unruly” (238-241). When reason dictates that Marianna should hate Angelo, she instead loves him more. Even the Duke (and transitively Shakespeare) admits that love causes people to act against reason!

Marriage blinds its followers to its own harm. For instance, the Duke says, “[Angelo] swallowed his vows whole…bestowed her on her own lamentation, which she yet wears for his sake” (224-227). He associates breaking vows with causing suffering. However, if Angelo and Marianna had a healthy relationship—a friendship or ARR--this would not have happened. When Angelo decided he did not want to marry Marianna, he would have gone his own way, and neither party would have felt bad. It would be wrong of Marianna to attempt to control Angelo, or force him to do things against his will, and as a friend she should not even want to; however, marital ideas have confused her. Marianna, if she were rational, would correctly feel sad because her brother and her wealth were lost at sea, which was a true loss. Angelo’s changing wants should not cause such grief. The Duke continues, “and he, a marble to her tears, is washed with them, but relents not” (227-228). The Duke feels Angelo should self-sacrifice, following an obligation long after his desire to do so has left him. Again, a character in Measure for Measure advocates harm over any action contrary to marriage. The Duke—quite explicitly—would rather harm Angelo than allow him to do anything against the marital status quo.

The Duke must advocate immoral ideas to achieve his desired outcome of protecting the establishment of marriage. Consider a proposition: if we grouped people into sets of three, then randomly slew one in each group, and gave his wealth to the other two, two people would benefit greatly for every one that lost, therefore the world would be a better place. It’s absurd! Trading two benefits, which may only be benefits in the Duke’s eyes, for one wrong is terribly immoral. However, the Duke says, “[If you choose to do this,] the doubleness of the benefit defends the deceit from reproof” (253-255). Basically, he says it’s ok to do one wrong because he gets two things he wants, or to put it graphically, it would be justified to rape one person if you had two orgasms. The Duke (and transitively Shakespeare) understands that his marriage laws harm some people, but prefers that to any contradiction of marriage as perfection.

What if some horizontal marriages were allowed? What would be so terrible about a few outcasts? The real question here is this: What happens to authority figures who make exceptions? The answer is simple, there is a real possibility a haze will clear from the eyes of the ruled, and they will realize their leader’s fallibility. If his laws are not always the best in all situations, perhaps that time a law hurt me, I should have had an exception! some peasant might think. Small freedoms lead down a slippery slope towards people requesting then fighting for freedom. However, the Duke (and Shakespeare) do not consciously understand it. This knowledge is embedded in anti-rational memes, so they act as if they know this, but are actually simply meme-controlled. That is one of the tricks of marriage that keeps Shakespeare so committed to it: a number of anti-rational memes tell him it’s terrific.

Measure for Measure could be a strong critique of marriage that exposes it as the harmful idea it is, contrary to autonomy. However, if Shakespeare understood marriage as such, he would not have clung to it. For instance, he ends the play with more marriages! Marriage as an important part of the social structure is firmly entrenched in Shakespeare’s mind. The Duke himself is caught admitting that love makes people act against reason. Isabella prefers immoral actions inline with the no-premarital-sex commandment to her brother’s life. Marriage, in her view, is more important than ethics! Only an utterly taken in Shakespeare could write this play without realizing what he had revealed. It is fitting that the Duke uses marriage as a punishment to end the play, for it truly is a terrible thing.

Thanks to Lulie Tanett for help improving the blog colors and design.

FYI I also added some caching, some links on my More page, and some links in the (edited) "I'm an American, atheist, classical liberal, and philosopher. I like Ayn Rand, Karl Popper, William Godwin & Ludwig von Mises." sidebar bio.

And I added *italics*, **bold**, ***bold-italics***, and >quote colors to comments. (Put one or more > at the start of the line for quotes.)

Update: I got a new linode with Debian instead of the very old ubuntu I had. I got new versions of nginx and passenger, and I got rails 2.3 LTS. I migrated from mysql to sqlite3. I added 3 db indexes and enabled gzip compression for nginx. The result: utf8 unicode is now fully supported including emoji in comments! And things should be more secure and a little faster. 😎

Update 2: I added an RSS Feed For Comments. You can now get updated on blog comments with an RSS reader, not just new posts.

Someone asked where the line is between vanilla sex and kink. There is no clear or principled line. It varies by subculture and is fluid over time. And the line has a substantial arbitrary, like fasion, trends and fads.

For a subculture, there are:

1) common sex acts ppl consider normal, admit to in public

2) common sex acts ppl are ashamed of, hide

3) uncommon sex acts

So 1 is "vanilla" (normal) and 3 is "kinky" (deviant). 2 is a grey area that people lie about a lot. It's normal, but the official line is it's deviant.

Someone claimed BDSM is kinky. Actually, some significant chunk of BDSM is normal in many subcultures. Some people seem to think BDSM is in category 3. But tons of it is category 2, and some is category 1.

You can see BDSM on mass market TV, for example USA's show Satisfaction.

Neil and Simon legitimize their partnership while Adriana introduces Grace to the world of BDSM.

Among other things, they have like a jail cell built into a house they lock a girl in and then use BDSM toys on her, on the show. It's softcorn pornagraphy meant to arouse its mainstream audience.

And who makes this? Comcast owns the TV channel. Comcast is huge and also owns NBC. Comcast's market cap is $150,000,000,000.

And most of the viewers feel so naughty watching it. That's part of the appeal. It's on fucking mass market tv. It's normal! But they somehow feel it's naughty at the same time.

Keeping things a big deal somehow is part of how ppl keep lasting interest in it. It keeps the excitement. It helps avoid it staleness. Over-hyping the amount of deviance of an activity is one way to keep it seeming like a big deal. It makes it more special, secrative and important.

It wasn't that long ago that, legally, you couldn't rape your wife. Marital rape excemptions ended in all 50 US states in 1993, but different legal treatment of marital and non-marital continues to this day in some states. Yet ppl act like rough sex is a rare, weird preference.

It wasn't that long ago that beatings were common. Beating children. Beating slaves. Beating wives. Is it any surprise at all that these ideas aren't all gone?

It's not like these things stopped b/c ppl were thoroughly persuaded and fully rationally understood something better. They didn't become Objectivists. It got suppressed in various ways, and lots of ppl are half-persuaded. It contradicts some liberal ideas with some popularity, but people don't really understand liberalism that well or thoroughly.

The ppl who are half-persuaded beatings are bad are a great target market for beatings-sex-play. It's toying with an issue they think is important and are conflicted about!

---

From the female side a bunch of the appeal of BDSM is like "you wouldn't do that. no way. that's off limits. omg u did! that's so intense!"

Some of the male side of BDSM is similar to parents who say "because i said so" and maybe hit their kids now and then. It's getting sex "because i said so", without reasons.

Some of the appeal for both sides is faking reality – pretending he's so great and appealing and dominant and alpha and worthy of submission to. Like a great leader, a great head of household you can trust and follow.

But they are using whips and ropes b/c that's all false and he has trouble getting her to submit, at all, without the props. E.g. he doesn't feel confident she won't stop sex at any moment if she isn't tied up. And she doesn't feel confident he'll keep her in the mood if she isn't tied up. She may want to stop.

Like William Godwin explains, using force is a confession of weakness. That still applies when it's fake.

Let us consider the effect that coercion produces upon the mind of him against whom it is employed. It cannot begin with convincing; it is no argument. It begins with producing the sensation of pain, and the sentiment of distaste. It begins with violently alienating the mind from the truth with which we wish it to be impressed. It includes in it a tacit confession of imbecility. If he who employs coercion against me could mould me to his purposes by argument, no doubt he would. He pretends to punish me because his argument is strong; but he really punishes me because his argument is weak.

Also girls like having no choice about sex. By which I mean pretending they have no choice. And the guys like feeling they have given the girl no choice. That makes them more manly and able to take or get what they want in life.

Things like ropes, beatings and rape fantasies (rape fantasies are very common, but commonly not admitted) help pretend it isn't voluntary. Putting effort into pretending it isn't voluntary is, by the way, such a fucked up thing. It really clashes with liberal values. That's one of the reasons people lie about it in public so much.

Alex Epstein, founder of the Center for Industrial Progress, sent out a newsletter today:

I’m writing this from the Republican debate in Las Vegas. I will be attending as part of an upcoming campaign to make America’s amazing energy opportunities a central theme of this election. I hope you’re as tired as I am of candidates trying to win on negatives—like Trump’s Tweets or Clinton’s emails—rather than giving us a positive, inspiring vision. In the next couple of weeks you’ll see what I believe America’s future could be with the right policies—and I hope you’ll join me in fighting for it. [emphasis added]

At first I read this as an attack on Donald Trump for writing negative tweets that insult people. I found that surprising because Trump is so good on energy, and Epstein is a one-issue guy (energy, energy, energy). Now I've decided the newsletter is confusing and I don't know what it means. I also find it weird to bring up the emails (a serious crime that ought to land Hillary in jail) next to the tweets.

Whatever Epstein meant, he should be a fan of Donald Trump. He should be gushing about Trump in his newsletter. He should be thrilled and telling me all about Trump's energy policies. Here's why:

Epstein has done such a great job of promoting industrial progress and fossil fuels that people sometimes falsely accuse him of being a paid shill for oil companies. Epstein wrote The Moral Case for Fossil Fuels.

In Crippled America: How to Make America Great Again, Trump presents a positive vision (notice the title) and he talks about energy. Trump comes out for fracking and developing all the US's energy resources. He attacks climate change, solar, wind, tree huggers, cap and trade, and the EPA. Trump emphasizes cost efficient energy, not green or sustainable energy. He says we have plenty of oil and gas underneath the US to last hundreds of years, and we should use it. He's in favor of development, drilling and pipelines. This is a similar message to Epstein's.

Here are quotes from Chapter 6, "The Energy Debate: A Lot of Hot Air", with my emphasis added:

Now these “experts” [on global warming] can’t figure out whether it’s getting too hot or too cold, so the new term is “extreme weather conditions.”

In his 2015 State of the Union speech, President Obama declared the biggest threat on the planet today is climate change. The biggest threat?! We have ISIS troops chopping off the heads of innocent Christian missionaries. We have a coalition of adversaries in Syria supporting a dictator who uses chemical weapons on his own people. We have millions of Americans who have mortgages greater than the value of their property, while middle-class incomes are stagnant and more than 40 million citizens are living at poverty levels.

And our president is most concerned about climate change?

I do agree that so-called global climate change is causing us some problems: It’s causing us to waste billions of dollars to develop technologies we don’t need to fulfill our energy needs.

The truth is, we have sufficient energy supplies in this country to power us into the next century—all we have to do is develop them. Among all the gifts that God gave to America was an abundant supply of natural energy. According to the Department of Energy, the natural gas reserves we have in the ground could supply our energy needs for centuries.

Researchers at Rice University in Houston, Texas, have estimated we might have two trillion barrels of recoverable oil, enough to last the next 285 years. Technology has changed so much in the last few years that a Goldman Sachs study has estimated that by 2017 or 2018, we could overtake both Saudi Arabia and Russia to become the world’s largest oil producer.

The oil is there for the taking; we just have to take it.

We need to be prepared to drill our own oil. And we need to take advantage of every opportunity, including approving the Keystone XL Pipeline.

One of the main criticisms of the pipeline has been the possibility of oil spills. Even the State Department has said the pipeline will be safe, and far better and safer than the existing system of transport. But mere possibilities shouldn’t prevent progress. You prepare for these situations, taking as many precautions as possible, and when they occur, you clean them up.

Our first priorities need to be approving the Keystone XL Pipeline and starting to drill everywhere oil is accessible.

There has been a big push to develop alternative forms of energy—so-called green energy—from renewable sources. That’s another big mistake. To begin with, the whole push for renewable energy is being driven by the wrong motivation, the mistaken belief that global climate change is being caused by carbon emissions. If you don’t buy that—and I don’t—then what we have is really just an expensive way of making the tree-huggers feel good about themselves.

The most popular source of green energy is solar panels. They work, but they don’t make economic sense. They don’t provide enough energy savings to cover the cost of installing and using them. They are the most highly subsidized form of green energy in America.

Some estimates claim it takes as long as several decades after installing solar panels to get your money back. That’s not exactly what I would call a sound investment.

It’s no secret that I’ve had serious personal issues with the supporters of wind turbines.

The bottom line is that we are going to remain dependent on oil and natural gas to fill our energy needs for a long time into the future. So if we are going to become energy independent, we need to keep drilling. The good news is that we have tremendous supplies of fossil fuels. We just need to decide to go after it.

We need to use every cost-effective method we have available to retrieve these resources. That includes fracking. For those who don’t know, fracking is a technology that involves injecting fluids into shale beds at a very high pressure to free locked-in resources. It makes it possible to recover vast amounts of oil and gas that otherwise can’t be reached through traditional methods.

While New York governor Andrew Cuomo has banned fracking, this technology has created an economic boom in North Dakota, Pennsylvania, and Ohio. There were more jobs created and less unemployment in those areas than practically anywhere else in the country. Upstate New Yorkers would like to replicate that boom in their region, lower taxes, and pay off massive New York State debt.

The bottom line on energy is that until there is a better “alternate” or “green” way of supplying our energy needs, we must put our resources to work for us, and now.

When it comes to energy (and immigration!), there's a lot to like about Donald Trump!

William Godwin surpasses David Friedman in his anarchism in some respects. Godwin's fundamental principles do not allow him to think that the Government is good at anything in a privileged way, that force is good for anything that persuasion can't do better (excepting self-defense), or that abolishing Government is a sacrifice in any respect. Friedman thinks we lose something with anarchy but it's worth it; Godwin thinks anarchy is best full stop, that there's no sacrifice. This is very important b/c it ties into Godwin's deep view that there is a right thing which everyone can be happy with in every way, so there's no necessary conflict.

everyone has some mistaken ideas. and some good ideas.

they don't know which are which. some ideas they think are good are actually mistaken. some ideas they think are mistaken are actually good.

so then we can look at lots of a person's ideas and evaluations and ask: what if this one is mistaken? how might they find out? how might they fix it? if they're mistaken and they never find out, that means they won't fix it. is that a big deal?

often it is a big deal, and there's no serious, realistic efforts going into finding out what one is mistaken about.

Displaymate.com has a lengthy article which appears to look at iPads in great detail. It presents itself as a rigorous comparison which a large amount of work was put into. It gives the impression that they dealt with all the details, carefully, so you don't have to. And it presents factual information which you are intended to believe is true.

An example statement they make is,

we examine in-depth the LCD displays on the Apple iPad mini 4, the iPad Air 2, and iPad Pro based on objective Lab measurement data and criteria.

Lab measurements! They sure put a lot of work into getting everything right. Didn't they?

But people suck at dealing with details. They may well have tried hard, but they have presented false information as if it were a fact. Here's the relevant part of their fact chart:



What caught my attention was the claim that iPad Air 2 is 7.8 inches tall while iPad Pro is 7.7 inches wide. I remembered Apple saying the Air's height and Pro's width matched during a presentation about new multitasking features. (As I remember it, Apple basically said you can fit a whole iPad Air on the pro screen and then have an area left over to the side for a second app.)

So I thought, huh, Apple fudged it. I thought they'd present an exact match here, but actually it's just pretty close.

But then I noticed the number of pixels does exactly match. The Air is 2048 pixels tall. The pro is 2048 pixels wide.

And the Pixels Per Inch exactly matches too at 264.

But if you have the same number of pixels, and the same number of pixels per inch, then the number of inches should also match. The chart contradicts itself.

So how many inches is it? Assuming the pixels and pixels per inch are correct then it's: 2048/264.0 = 7.757575 repeating.

So the actual value is between the 7.7 and 7.8 inches given, and a little closer to 7.8. Both numbers should have been rounded up to 7.8 inches since that's closer.

I wouldn't mind so much if both numbers were rounded the same direction, either way. But getting the same number in two adjacent boxes on your chart, and then rounding one up and the other down, is really not OK. This is a factual error caused by a methodology error. Whatever one's policy for rounding numbers, the same policy should be used for the entire article.

I emailed the article author and will update this post if it's fixed. The article did invite comment. As usual, I understand that mistakes can happen. We'll see if he's willing to fix it. Willingness to fix mistakes, or not, is even more important than making mistakes, or not, in the first place.

---

Update 2015-12-03:

They replied:

You have incorrectly assumed that both displays have exactly the same 264.0 ppi in order to calculate their width and height. This is a technically weak assumption.

We used the published screen size to calculate the width and height. Both methods are subject to a round off error of the Apple published specifications, but ours is the more technically sound one because it only assumes that the displays have square pixels, which is true for all current high-end displays to very high precision.

A 2732x2048 pixel 12.9" screen is 7.74" by 10.32" which is 7.7 x 10.3 as published

A 2048x1536 pixel 9.7" screen is 7.76" by 5.82" which is 7.8 x 5.8 as published

So they did it by assumption, not lab measurement. And they did the calculation using Apple's tenths of diagonal inches number as exact, even though it's easy to guess that's rounded. Basing their numbers directly on Apple's rounded tenths of diagonal inches is not a reasonable way to end up publishing that two things which are basically the same length are a tenth of an inch apart.

The 264 PPI number from Apple is also rounded, but it could still easily be that the displays Apple gives the same PPI number for are actually made in the same way and have the same PPI. PPI is not something Apple would want to manufacture in lots of slightly different variants, they'd prefer reuse. (If Apple was fine with slightly different PPIs, you'd often see PPI numbers that are a couple apart, rather than different by at most a rounding error, but you don't see that in Apple's lineup.)

So I still think DisplayMates are mistaken and their article is unreasonable. And I think it's bad to publish seemingly contradictory numbers without saying the methodology you used so that readers can judge for themselves if it's reasonable. And they've refused to change this.