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When Evidence is Mediated and Marketed: Does Pitching Out Corrupt Within?


-- Edward Tufte

It might be useful to carefully distinguish between events or raw facts and our explanations of events. Though definitions can be difficult, one operational test we can apply is how insane it feels to deny events or raw data, vs. the relatively free choice we have in determining explanations.

Once we label something "evidence" we have started to attach interpretations to events. I would propose that evidence is always mediated and, according to the narrow of scope of the objectives of the speaker, marketed.

For the purposes of investigation, let "weak corruption" be the type that lulls someone into believing one's marketing message outside the original scope of objectives. Let "strong corruption" be the type that denies anything out of their scope of objectives. While those corrupted in the first sense may occasionally make unwise leaders; those corrupted in the second sense may become self-righteously and systematically destructive of relationships, culture, society, etc.

We rarely pay much attention to anyone who hasn't shaped events with a story. We seem to be innately interested in well-crafted interpretations of events. Maybe a better measured of corruption is in the scope of objectives respected by the dialog surrounding the story than the degree to which the story supports a narrow scope of objectives. Good information architecture can often be said to be about respecting the dialog surrounding the story.

-- Scott Hendrickson (email)

Thanks to Kindly Contributor Tchad for the spotting "significant" and tactfully pointing out its problems.

On Tchad's English example of the "sexed up" case for British intervention in Iraq: in my last paragraph the phrase "evidence fixed around policy" is a quiet reference to a phrase in the notorious Downing Street memo describing US WMD intelligence practices 6 months before the war started. The WMD affair is just one more dreary episode in a long history of chronic problems in intelligence agency evidence-processing, as those agencies tend to report what political authorities want to hear. The political science literature on intelligence agencies for at least 50 years has contemplated this exact issue: how pitching out corrupts within.

-- ET

Dear Dr. Tufte,

Is the citation (2) for the Martin Amis book (bottom of your page) a typo "New Yori 2001"?

This looks to be another fascinating discussion thread, I cannot wait for the book.

Cordially, Alex

-- Alex Vacca (email)

Is this part of the "Corrupt Techniques in Evidence Presentations" chapter?

A few thoughts:

This section concentrates on the effects of distortions, purposeful or not, in evidence as it is re-presented to ever widening populations. Such programs take advantage of our native desire to believe in the goodness of people: "they wouldn't say it if it wasn't true." They also prosper on our belief that laws and regulations will prevent such obfuscation: "they couldn't say it if it wasn't true."

There is also the refocusing of mediated evidence from a wider population back to the individual, especially with regard to public opinion and public policy. A report is generated (and let's just say it's properly done without prejudice for a particular viewpoint), parts of this report are interpreted (cherry-picked) by a small number of people, or an organization, with a particular viewpoint to promote and broadcast to a wider, perhaps pre-selected, audience, who then exert some form of political pressure which passes back through a handful of individuals (lobbyists, congressional staffers), who then reinterpret such pressure as evidence and re-present it to a policy maker, who then acts on this by, among other things, crafting legislation (or at least attaching his or her name to a bill) or by voting one way or the other on pending legislation. This process may go through several generations of refocusing and further refocusing (back out to the wider population-back in to the policy maker...), sort of an evidentiary laser generating process, until the latest iteration is taken (or passed off as) as an original report.

Secondary presenters may not state who's funding their operations. They also may cite related research ("performed at a major university") in support of their program without providing proper references to said research. Alternatively, they may provide such an overwhelming display of citations, disclaimers, references and other fine-print justifications that we accept their headline claims since all those notes must mean they did a really good job of research and reporting.

Leaks to journalists can be a risky road to travel with regard the dissemination of original information. While it may be the only way to get sensitive information past higher levels of information control, it does have its pitfalls. When you do this, you give up your authorship, at least for a time, and hand it over to the journalist, necessarily a re-interpreter; you're cited only as an unnamed source. The veracity of your information, in the public mind, lies solely on the reputation and integrity of the writer and the paper (for instance) and counts on readers to believe it because "they read it in the paper." If they don't believe the paper, they won't believe you either.

-- Steve Sprague (email)

One of the more amusing -- and informative -- abuses of the scatterplot that I've seen was in a college embryology lecture. In the semester's first lecture, the instructor drew on the chalk board an abscissa with three categories: Primary Literature, Review Articles, and Textbooks. The ordinate was labeled "truth". A steeply descending line was then drawn through the graph-space.

The message could not have been clearer. The assigned reading included a couple of book chapters and several research papers a week. The tests were impossible if you hadn't read the papers.

-- Alex Merz (email)

These are the new concluding pages of a long chapter on evidence corruption (elsewhere on this thread); some examples in that chapter are relevant. That chapter is at

The theory here is based, in part, on the evidence collected (largely by several editors of the major medical journals, including The Lancet and NEJM) on the process for testing new drugs and the big compromises about the distribution of drug-test evidence that medical schools make in exchange for payments for running clinical trials. In an early draft of the essay above, I listed all the restrictions that drug companies place on evidence collected in new drug research and then suggested that alert consumers of evidence should not trust evidence that emerged under that set of restrictions. Earlier in my chapter on evidence corruption, there is definitive evidence about the relation between the quality of research designs in drug testing and the enthusiasm for the benefits of the drug (the worse the design, the greater the enthusiasm). And a few other examples in that chapter might be relevant.

What happens to evidence about new drugs is a strategic case: an important issue of broad scope, intense evidence collection with restricted distribution, sometimes undistinguished monitoring by the Feds, and an enormous amount of material produced by the bureaucracies of secondary presentations.

One other inspiration was a NASA scientist who complained to me that every report of scientific evidence had to go through the PR department.

Another inspiration came from the NASA emails going around Houston when the Columbia was damaged but still flying: those emails referred to the Boeing analysis of Columbia's plight as the "Boeing PowerPoint Pitch". The pitch language had penetrated all the way to the very most serious analysis done. The WhatPoint Pitch? The PowerWhat Pitch? The PowerPoint What? (I'm saving this anecdote for the PP chapter).

In several ways, the PP essay (which follows the corruption chapter) provides evidence about the bureaucracies of secondary presentations, especially the section on PP guidelines at the Harvard School of Public Health.

On intelligence agencies and their problems in distinguishing between detective work and pitching: there is some 50 years of political science literature on intelligence agencies about exactly this problem.

Perhaps a sidenote delineating the recent work on evidence restriction in big pharma work would be useful. And perhaps one to the political science literature on intelligence agencies.

To develop the theory fully, however, would require a long essay, similar to the evidence in the essay on the cognitive style of PP. Or another book. By someone else.

-- Edward Tufte

For Kindly Contributor Alex Merz: How wonderful! Any chance of contacting the creator of the scatterplot linking truth to distance from the primary source for an original sketch?

-- Edward Tufte

I took a course called Drug Action and Design in the spring; the professor, an immunologist currently working at the National Institute for Alternative Medicine, used primary sources in a way similar to that of Professor Merz's embryology prof, and she expressed the same skepticism of review articles and textbooks. Our assignments were to present articles to the class. Some of her choosing, some of our choosing. Her stated goal was to teach us how to discern good original research from bad. And she regularly filleted our articles. She was much more polite in her admonishment of the student presentations, but she wasn't going to leave the students with bad analysis. Just about the time I could get through a NEJM article with only occasional reference to a dictionary, now I'm slowed down again trying to figure out what a Wilcoxon matched-pair signed-rank test is, and whether its use indicates obsfucation by the investigator.

On the completely opposite end of the spectrum is Paul Starr's The Social Transfomation of American Medicine. His opinion of medicine in America is so obvious from the first page that I actually found his bias helpful in separating fact, opinion, and manipulation of the facts.

Interestingly, both my professor and Starr are opinionated and know it. It made for lively conversation, lively reading, and healthy skepticism.

On pharma in particular, here's what I recently posted on my blog:

Having interviewed with some of the pharma companies before getting into Tulane I'm pretty much convinced their young, motivated sales reps are brainwashed by headquarters to buy into some morally corrupt ideas about education (sales pitches) without any obligation to make all the relevant facts known to their students (your doctors), indeed, an obligation to withhold disparaging information (that might affect their commision) is strongly advocated (enforced).

I think one of the key things the pharma companies do is to get some of these reps before they're 25, before that critical bit of prefrontal cortex develops that is responsible for risk analysis and judgement. I was amazed by how innocent and forthright the young sales representatives were. I think they truly believe in what they're doing. I can easily see the pharma HR and marketing departments holding meetings along these lines:

Marketing: You've got to target the new college grads for these sales rep jobs.

HR: Why?

Marketing: Our indoctrination works best when they're young and they make tons of money for their age bracket, enough to qualify for a mortgage. if we can get them saddled with debt before they figure it out, we'll have garunteed buy-in when the time comes for the next hard sell. And that makes for less turnover.

HR: We'll have a booth at State U tomorrow.

And you should see the booths. Bigger, brighter, all the graphs have a positive slope, and the reps on hand are always young and beautiful.

-- Niels Olson (email)

Here's a good one: the R & D office at EPA wants to spend up to $5,000,000 to PR consultants to ghostwrite articles "for publication in scholarly journals and magazines" among other things:

From the NY Times story: "Donald Kennedy, the editor of Science magazine and a former head of the Food and Drug Administration, said in a telephone interview on Saturday that he found the idea of public relations firms ghostwriting for government scientists "appalling."

"If we knew that it had been written by someone who was not a scientist and submitted as though it were the work of a scientist, we wouldn't take it," Mr. Kennedy said. "But it's conceivable that we wouldn't know, if it was carefully constructed."

He added that the practice of putting public relations polish on scientific work has already been practiced by industry. "We had seen it coming in the pharmaceutical industry and were sort of wary about it," he said. "The idea that a government agency would feel the necessity to do this is doubly troubling." "

-- Edward Tufte

Here's the permanent link to the NYT article ET cites above. Courtesy of Aaron Swartz's NYT Link Generator.

-- Niels Olson (email)

Thank you Kindly Contributor Niels, it's good of you to point out Aaron's link generator and its great value. I didn't know about it.

Aaron visited here yesterday and we had a good long walk and talk.

-- Edward Tufte

An interesting article on (self-reported) bad behavior among US scientists: From the article: "Of 3,247 early- and mid-career researchers who responded, less than 1.5% admitted to falsification or plagiarism, the most serious types of misconduct listed. But 15.5% said they had changed the design, methodology or results of a study in response to pressure from a funding source; 12.5% admitted overlooking others' use of flawed data; and 7.6% said they had circumvented minor aspects of requirements regarding the use of human subjects."

-- Eric Halpern (email)

It would be good to have similar data for secondary presentations of the primary research. Here are some research designs:

Method 1: start with a sample of secondary presentations then match them up against the primary source. Example: Richard Feynam's experience on the California textbook review committee, recounted in Surely you're joking Mr. Feynman. Here is a link to Feynman's discussion: This link leads to The Textbook League, a newsletter which reviews school textbooks and finds lots of foolishness.

Method 2, the other way around: start with a primary source and then track all the secondary presentations of that single primary.

I once took George Miller's "Magical Number 7 +/-2" paper and tried to track down some secondary accounts. This informal census yielded the commentary in the "Cognitive Style of PowerPoint" and in our thread

A variation on Method 2: start with classic primary reports in various fields and then see how textbooks, review articles, newspaper accounts, weblogs, and so on then interpret the classic. The result: a series of studies in the degree of corruption in secondary presentations. There is surely a research literature already on this topic.

-- Edward Tufte

Sometimes the secondary communications are confronted; problems may arise: "In Training Video, Merck Said Vioxx Did Note Increase Risk of Heart Attack," The New York Times, July 21, 2005: oref=login

The archive link to the article is:

Near the end of the story, there is an exchange which suggests it may be not be a good course of action for a witness to spar with an experienced litigator (the witness says that the lawyer is playing games, the lawyer for the opposing side responds with "this is not a game, my client is dead." Long ago I assisted with an antitrust case run by a sharp and quick lawyer. His staff recounted the following story demonstrating his articulate quickness: the opposing side had not produced a possibly harmful document early in the case; then it appeared that the document might be helpful and the document, lo and behold, showed up. The antitrust lawyer asked what accounted for this runaround. The reply came: "A secretary had stored the document in an inaccessible place." The lawyer immediately responded "How did she get it there?"

The same articulate quickness by experienced litigators is sometimes found when they cross-examine very distinguished economists in anti-trust cases.

-- Edward Tufte

I often find it revealing to ask:

"Is this an evidence-based decision, or decision-based evidence?"

I can't remember where I first heard this, but I think it was about the British Labour government, quoting "policy" rather than "decision".

-- Chris Horton (email)

This meta-analysis Lancet presents a particularly persuasive tree diagram on page five arguing that Merck had data indicating the risk of myocardial infarction in 2000 and that the risk was well documented by the end of 2000. The meta-analysis is republished here on the site of attorney F.G. Vaughn Marshall. Basically, as soon as they went to phase three trials with lots of patients the risk revealed itself definitively. The cumulative number of patients indicates that Bombardier's study of 8076 patients in early 2000 was the grand piano that broke the camel's back.

The Bombardier study's effect also highlights the arbitrary nature of the 95% confidence interval. The authors declare the findings against Vioxx to be unambiguous after one more study, that of Geba. Geba's contibution to this meta-analysis, however, with less than a thousand patients, amounts to not much more than a rounding error in Bombardier's wake.

-- Niels Olson (email)

On page 5, note the drift of the effect and tightening up of the error bars over time. This is a fine example of the Evidence Decay Cycle described in the Beautiful Evidence chapter on evidence corruption: msg?msg_id=0001et&topic_id=1&topic=

-- Edward Tufte

On "Fact", selling out and management consulting

Most contributors to this thread have cited studies in medical/biological fields, hardish sciences that often fall under the limelight of public scrutiny, and thus the need for vulgarization. (for which word the thesaurus can't make its mind between adulteration and clarification ...). I would venture that the Evidence Decay Cycle (E.D.C) is less sharp in presentations of Physics or Chemistry experiments.

At the other end of the spectrum, evidence in soft sciences exhibit short half lives, the E.D.C being rapidly followed by the "Everybody knows", aka "Studies show", aka "Family Feud" phenomenon. Here I must confess to a cardinal sin : being a management consultant. As such, I'm often pressed to base my problem solving, my presentations and my conclusions on "Fact", and preferably on "Accepted Fact".

Two of my favorite are the following :

Exhibit A: Studies show that out of everything that you worry about : 40% will never happen, 30% has already happened, 12% is about your health, 10% are problems whose effects will cancel out and only 8% are legitimate and need attention.

Exhibit B: Studies show that we remember : 10% of what we Read, 20% of what we Hear, 30% of what we See, 50% of what we See and Hear, 80% of what we reformulate, and 100% of what we Reformulate while in situation

Needless to say, my (less than strenuous) research has never uncovered said studies. And I will not go into a detailed analysis - at least not in this forum - of why these "Facts" are obviously not "True" (hint, can you say 7+/- 2?).

However, it is interesting to note that when I've attempted to raise the point with my colleagues, I've been rapidly catalogued as the resident nerd.

Moreover, I've actually given a seminar where those two sets of numbers where used, and trainees dutifully wrote them down : fortunately for me, no one started discussing the numbers ...which shows the level of mid range management's gullibility / lack of critical eye.

A final point on the use of such "Fact" as a backbone to my job, and to go back to "Pitching Out" and "Corruption". It is a given that my firm will never win a contract if we cannot gain the confidence of our future client. This confidence comes from many things : a few white headed consultants, charisma, good delivery, knowledge of the subject at hand ... but I've never seen it won so rapidly as with a few well placed "studies show...".

I've taken the "moral" position that as long as in my day to day job, I'm professional, honest, and trustworthy with my clients, it doesn't matter if I've had to bend a few rules to convince their bosses to hire me. Of course, a drug marketer who does the same thing is an amoral, inhuman beast ... fine lines.

-- Paul ATLAN (email)

ET suggests that creators of evidence-based reports "...should prepare their own secondary reports to replace the repackagings." The first repackaging and the best defense should be the "executive summary." Replace some of the secondary repackagings by presenting a good accurate executive summary, perhaps a little longer than the term generally implies. Even if the consumer --at least the government official and journalist consumer-- has the whole report, all that 90 percent of them will read is the executive summary. Most will just lift whole sentences and paragraphs from it, which mitigates mischief to some degree.

-- Peter Morelli (email)

My essay mentions, as an example of how pitching out corrupts within, "the chronic problem of government intelligence agencies: once the collection and selection of evidence starts to become fixed around a pre-determned policy line, intelligence agencies may become permanently unintelligent, confused about the boundaries between detective work and marketing."

See Fred Kaplan, "Beyond the NSA Scoop: A Tale of Intelligence Fiascos," a review of James Risen's book, State of War:

-- Edward Tufte

The CIA Center for the Study of Intelligence has some interesting publications that touch on the issue.

I find it interesting to read some of the discussions about policy versus analysis. See the June 2004 roundtable and the 1999 Psychology of Intelligence Analysis.

-- Michael Eglinski (email)

i found the original text, and the responses/conversation here pretty fascinating...I'm an artist, about to open a show exploring war and the question- how, as a nation, do we decide what to kill and die for?

in trying to say something not available on the nightly news, and avoid spending energy repeating liberal or conservative perspectives on today's war, we have found ourselves deconstructing story

and asking questions about the relationship between a citizenry hooked on narrative to a phenomenon far too complex to be explored & ethically wrestled with through narrative and the relationship between pitching one's leadership and pitching a construction of global affairs dependent on war as plot

mediation of identity, evidence as backstory

marketing as national dialogue...

thanks for food for thought.

-- michael rohd (email)

Credibility of analysts of information technology, an interesting Information Week article by Paul McDougall and Larry Greenemeier at

The article suggests that there are differences between IT research firms and, say, Consumer Reports.

-- Edward Tufte

See CBS News, "Rewriting the Science:"

-- Edward Tufte

See Haditha Evidence.

-- Edward Tufte

NYT Haditha Article: Does Pitching Out Corrupt Within?

What is your thinking on this Haditha article, that the early statement, put out like so many other "first and last report this incident" statements, may have created a sense among the early actors, like Capt. Pool, as further facts came back from the unit and the community, that they had to defend the initial position, no matter how absurdly weak it was apparently becoming?

-- Niels Olson (email)

Here's an abstract from a paper that has just been published, which refers to ET's essay. It may be of interest to some of you.

In lecture halls, in secondary school classrooms, during training workshops, and at research conferences, PowerPoint is becoming a preferred method of communicating, presenting, and sharing knowledge. Questions have been raised about the implications of the use of this new medium for knowledge dissemination. It is suggested PowerPoint supports a cognitive and pedagogical style inconsistent with both the development of higher analytical thinking skills and the acquisition of rich narrative and interpretive understanding. This paper examines how PowerPoint invites and seduces educators to reshape knowledge in particular ways, and subsequently how this knowledge is presented to students in the classroom. The particular forms of knowing, relating, and presenting with PowerPoint are decided in part by teacher habituation to the software tool's default patterns, but also by the very nature of the presentation medium itself.

Adams, C. (2006) PowerPoint, habits of mind, and classroom culture. Journal of Curriculum Studies, 38 (4) 389-411.

-- Dean Madden (email)

The New York Times has an interesting article on Weighing the Costs of a CT Scan's Look Inside the Heart ( There is a debate amongst cardiologists on the utility - or lack thereof - of CT scans of the heart. Some of the proponents of using CT scans of the heart happen to be those have purchased the machines and need to utilize it.

I was struck by the following statement from Dr. Hecht (page 5 of the article), who supports the use of CT scans for diagnosis:

Cardiologists like Dr. Brindis hurt their patients by being overly conservative and setting unrealistic standards for the use of new technology, Dr. Hecht said. "It's incumbent on the community to dispense with the need for evidence-based medicine," he said. "Thousands of people are dying unnecessarily."

-- Vaibhav Vaish (email)

I have been following this thread with interest and am reminded of the essay by Stephen J Gould on the "creeping fox terrier clone". This is a classic example of how an original phrase can repackaged and cloned over successive generations of textbook until the information becomes 10th hand and passes into accepted wisdom. The fox terrier was first quoted in a book some 100 years ago as being the most appropriate approximation for the size of one of the earliest horse types, Eohippus. It is unlikely that most readers today have the remotest idea how big a fox terrier is, yet the anaology is remarkably persistent; see for example, (accessed 29.6.08). Interestingly, however, Wikipedia cites the Gould essay and explains the reasoning behind the original comparison. ( , accessed 29.6.08) Perhaps an example of Wikipedia's reliability?

-- Jim McDougall (email)

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