Pie chart zaniness from Fox Chicago News, reported by David DiSalvo (True/Slant).
UPDATE: I originally said this was from Fox News; commenter AJK points out that this was Fox Chicago News, a local Fox affiliate.
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jccamp says:
But...but it’s been validated via overlay with tree ring density...
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November 30, 2009, 7:07 pmcalattnyken says:
Perhaps Foxnews “need[s] that extra push over the cliff....”
BTW, if you don’t laugh out loud while reading those lines you are not human.
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November 30, 2009, 7:16 pmAnthony says:
The numbers are perfectly possible, as long as people are allowed to support more than one candidate. Of course, using a pie chart for the result is inappropriate (though in this case, not necessarily all that deceptive; if you’re trying to show relative support, the slices of the pie are reasonable enough in size). If I had to guess, the numbers are actually favorable ratings from Republicans. Based on Gallup Palin has lost ground.
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November 30, 2009, 7:16 pmjeebus says:
When I first read this i expected the chart to explain what percentage of the budget deficit resulted from obama’s spending...it seems to be an area where conservatives have lost even the most basic of math skills.
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November 30, 2009, 7:25 pmDaniel Chapman says:
Of course the numbers might be right, but it’s not a PIE CHART. Pie charts by definition show percentages of the whole and add up to 100.
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November 30, 2009, 7:44 pmpot meet kettle says:
they should’ve just made the pie higher.
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November 30, 2009, 7:48 pmRyan Waxx says:
Definitions of pie chart on the Web:
* a circular chart divided into triangular areas proportional to the percentages of the whole
wordnetweb.princeton.edu/perl/webwn
* A pictorial graph in the shape of a circle, with segments representing related proportions
en.wiktionary.org/wiki/pie_chart
* a graphic that displays parts of the whole, in the form of a circle with its area divided appropriately.
http://www.cliffsnotes.com/WileyCDA/Section/Statistics-Glossary.id-305499,articleId-30041.html
* A graphic representation of quantitative information by means of a circle divided into sectors, in which the relative sizes of the areas of the sectors correspond to the relative sizes or proportion of the quantities.
http://www.glencoe.com/sec/busadmin/marketing/dp/mktg_resrch/gloss.shtml
* Symbols are pie charts that range from empty to full. The first interval or category will have an empty pie as its symbol, the last interval or ...
http://www.geode.northwestern.edu/myworld/tour/pages/glossary.html
* A graph that represents summary data or percentages as wedges in a circle, or pie shape, so that the relationship between the data can be seen and ...
erc.msh.org/staticpages_printerfriendly/2.2.3_gmt_English_.htm
* A type of chart divided into sections of a circle, drawn from a single Y-axis value and used to illustrate the relationship of parts to the whole, particularly useful for emphasizing one specific element.
planning.ucsc.edu/IRPS/Dwh/bobgloss.htm
* A graph that displays data in a circular format. Each section of the pie chart represents a portion or percentage of the total.
http://www.raymondgeddes.com/lesson-plans/math-vocabulary.html
* A chart or graph in which a circle represents the whole and is then divided to represent
http://www.dete.sa.gov.au/limestonecoast/files/links/Glossary_of_mathematical_t.doc
... Nope. I’m not seeing “must always add up to 100″ being a consensus.
It seems to me, that the critics here and at the link know a lot less then they think they know.
Do try to open the window before throwing eggs out. You’ll end up with less on your face.
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November 30, 2009, 7:48 pmBenjamin R. George says:
Here’s the poll it seems to have been based on. It looks like they were reporting the percentage of Republicans polled who had a favorable opinion of each of the three. They appear to have chosen both their words and their graphics rather poorly.
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November 30, 2009, 7:59 pmwolfefan says:
Hi Ryan —
In all your definitions, doesn’t “the whole” mean 100%? I mean, it’s like the stupid cliches about giving 110% — you can’t. 100% is all there is. 100% of something is “the whole” of it.
This pie chart appears to represent 193%. 193% of what? Based on the chart, the pollsters asked everyone(100% of the people) their opinion, and then asked 93% of them their opinion a second time?
It’s no big deal, and it’s not media bias or anything — it’s just someone at Fox who doesn’t know how pie charts work. Just chuckle at it and move along, instead of trying to defend it. Snopes already debunked some state legislature trying to redefine pi — I don’t think they genuinely need to take on whether or not Fox is trying to redefine 100%.
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November 30, 2009, 8:06 pmRyan Waxx says:
> In all your definitions, doesn’t “the whole” mean 100%?
Well, if all my definitions had the word “whole” or some exact synonym, then you’d might have a point. But they don’t, and you don’t.
It seems to me an unusual use of a pie chart, but that’s because it’s based off an unusual style of poll. The pie shows the proportions accurately — therefore it is communicating the information effectively.
It seems more to me, that the unusual use of the chart hurt the OP’s pretty little head, and rather than ask if there was any real problem with the method (as opposed to imaginary ones based on false assumptions about the “proper” use of that style of chart), he chose fashionable bashing.
No, there’s something amusing, and that’s the OP who thinks he knows more than he actually does. Just chuckle and move on.
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November 30, 2009, 8:27 pmLN says:
Awesome, Ryan Waxxx defending this pie chart on the grounds that it’s round.
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November 30, 2009, 8:29 pmzuch says:
They were just trying to be fair and balance the 63% hanging so heavily on one side of the pie chart with a compensating 70% on the other....
Cheers,
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November 30, 2009, 8:31 pmU.Va. Grad says:
I think you’re the eggy one, Ryan.
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November 30, 2009, 8:31 pmanonymous coward says:
Yeah, just try telling that to Chuck Norris :)
–In all your definitions, doesn’t “the whole” mean 100%? I mean, it’s like the stupid cliches about –giving 110% — you can’t. 100% is all there is. 100% of something is “the whole” of it.
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November 30, 2009, 8:32 pmGD says:
For what its worth (just the wikipedia entry for Fox TV channel without a citation):
“Despite the common ownership, Fox News is largely autonomous from the Fox network”
You (and others) are referring to Fox News (i.e., Fox News Channel, the evil member of the VRW conspiracy, etc.) here, but this is Fox TV local news. They always have seemed distinct to me and the wikipedia entry provides some support.
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November 30, 2009, 8:33 pmRyan Waxx says:
Awesome, LN using a strawman.
Oh wait, that happens every day. Lets move along.
At least his “on the grounds that it’s round” was 100% made up from scratch. He does practice what he preaches.
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November 30, 2009, 8:36 pmLN says:
Ryan is right though guys, the numbers may not add up to 100% or even represent non-overlapping parts of the voting population, but at least the chart clearly shows that you can’t tell who has the greatest amount of support unless you actually show the numbers. And isn’t that valuable in itself?
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November 30, 2009, 8:39 pmRick H. says:
Ryan Waxx: In the definitions you linked to, the phrases “the whole” or “the total” or “full” should reasonably be inferred as meaning 100%.
A pie graph is one of the most basic and commonly understood charts in statistical communication.
I’m not quite sure where you’re seeing enough wiggle room to justify the smug pomposity.
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November 30, 2009, 8:48 pmLN says:
“A graph that represents summary data or percentages as wedges in a circle”
“A pictorial graph in the shape of a circle”
“A graph that displays data in a circular format.”
“a circular chart”
In other words, this is a good pie chart because it’s in the shape of a circle. (“Relationship of parts to the whole”... oh no that’s not really critical.) I get the feeling that Ryan may have been responsible for putting this particular chart together.
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November 30, 2009, 8:49 pmRyan Waxx says:
If you have a chart showing how people voted on something, but they were allowed to vote for more than one thing, then the total of the percentages will be greater than 100%. Yes, normally votes don’t work that way in this country. However many European countries do allow this form of voting. I had no idea that the VC liberal crowd was so provincial that they cannot even grasp the idea of a multiple-choice voting system or its results.
If fox had normalized the pie chart wedges to total 100%, then they would have had to report different numbers on the chart than the actual percentages tuned out to be. It says something, that certain people here are so insanely rabid that if Fox doesn’t distort their charts to please the commenters’ jr-high-school understanding of charting, that the catcalls start.
I wonder... had fox changed the numbers, would these same wise commenters then begin to gibber about how the numbers didn’t match the poll?
Who cares? It’s Fox. Right?
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November 30, 2009, 8:50 pmchart viewer says:
Setting aside conceptions of what a pie chart should be, the 63% slice appears to be at least as large as the 70% slice.
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November 30, 2009, 8:54 pmLN says:
Hey Ryan, you know there are other ways to present information in graphic form, right?
For example, if you wanted to compare unemployment in a bunch of different countries, it doesn’t make too much sense to use a pie chart. Instead you may want to use a line graph or a bar graph or something else.
Don’t cry, dude. It’s OK, you don’t always have to whine about being oppressed by the chart Nazis and the feminists and the liberals and the hippies and the environmentalists and the Muslims. Man up.
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November 30, 2009, 8:57 pmBT says:
Since the station is in Chicago maybe the pie chart is just a leftover from the last election showing voter turnout.
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November 30, 2009, 9:01 pmwolfefan says:
Hi Ryan —
I get what you’re saying, but I think a pie chart is commonly understood to represent 100%. It’s not the right chart to choose to convey this kind of data. It’s confusing to the average person who doesn’t have easy access to the underlying data. The fact that it’s confusing at first glance means it’s ineffective, and is proven by the fact that Our Distinguished Host (who has a better understanding of statistics than I can ever aspire to) found it odd. A junior-high understanding of charting is what the news outlet should be aiming at. (FWIW, I don’t think this kind of data is worth conveying at this point, but that’s another issue.) I wouldn’t have criticized them for normalizing to 100% — I wish they had — but I can’t speak for others. If it’s a local Fox station as opposed to the network, the error is more understandable.
Last week David Nieporent was called a loony lefty, and now Eugene Volokh is part of the VC liberal crowd. :)
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November 30, 2009, 9:01 pmRyan Waxx says:
> Hey Ryan, you know there are other ways to present information in graphic form, right?
And as chart Czar, you determine which ways are permitted to non-news-agencies like Fox News, eh?
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November 30, 2009, 9:08 pmRyan Waxx says:
Respectfully, I disagree. Read my list of definitions. Almost all of them emphasize that this style of chart is meant to show the size of each respective share... and this chart does that job effectively. The only potentially confusing part is the numbers... and the numbers are merely labels on the pie, and even that confusion is dispelled when you read the article.
The only people who are actually confused by it are people playing ignorant to score points, which is somewhat less than amusing.
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November 30, 2009, 9:12 pmLN says:
The chart does not effectively show the size of each respective share... you need the actual numbers to see that the red slice is the largest one.
“Chart czar”... well I called Chart Nazi, that’s close enough right?
Funny stuff: “Fox has the right to use whatever graph they want to use. I’ll give you my copy of Microsoft Excel when you take it away from my dead, cold hands.”
Is there a bigger victim on this site than Ryan? Does he cry himself to sleep every night?
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November 30, 2009, 9:21 pmLeo Marvin says:
The irony of implying Eugene would find something fashionable about bashing Fox is almost beside the point. Toxic, belligerent comments like this one corrode the site, bit by bit.
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November 30, 2009, 9:26 pmJef says:
I know this is huge fun, but this isn’t from Fox News, it is a Fox Broadcasting Company’s affliate in Chicago.
Yeah, yeah, I know, too good to check.
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November 30, 2009, 9:27 pmAJK says:
Stupid as this is, it appears to be the local Fox affiliate in Chicago, and thus has nothing to do with Fox News (just as the local NBC affiliate has nothing to do with MSNBC).
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November 30, 2009, 9:34 pmRyan Waxx says:
That’s an unintentionally hilarious comment, given the one directly above your post.
But you’re quite right. The commonly accepted form of criticizing the poster here at VC is to generically deplore the lowering of quality of posts here at VC. Consider it deplored.
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November 30, 2009, 9:36 pmravenshrike says:
LN, you do realize that 3.5 of the definitions you posted technically support Ryan don’t you? I mean, yeah, it was a bad idea without a wall of text explaining the chart, but as pie charts go it’s perfectly acceptable.
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November 30, 2009, 9:38 pmravenshrike says:
Oh, and LN, the chart does show the correct proportions, however they modeled it as a 3d object and then tilted the result to look spiffy. This introduced perspective bias making the red segment seem smaller than it is.
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November 30, 2009, 9:40 pmgeokstr says:
Chicago math. That explains it.
Obama and Ayers spent 100 million dollars there in the 90’s to improve education by exactly 0.00%. The broadcasters must have gone through the Chicago school systems.
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November 30, 2009, 9:45 pmNels Nelson says:
It doesn’t bother me that the numbers don’t add up to 100. As “chart viewer” said, the real problem is that you cannot tell size differences among the pie sections, which is why they had to overlay the numbers. Using a pie chart for such similar numbers does not work.
A bar graph with three bars would have better displayed the minor difference in support.
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November 30, 2009, 9:52 pmLN says:
It’s not “perfectly acceptable,” it’s silly and dumb. And that’s because the “whole” of the pie chart has NO meaning — the sum of the three figures does not correspond to anything in the real world. If you don’t understand that pie charts relate parts to the WHOLE, then you can trot out all the painful definitions you want, that doesn’t help.
Raise your hand if you learned what a pie chart is by reading some definition provided by a geomapping software company. And let me know if you use pie charts to compare unemployment rates in different states, or GDP growth over different intervals of time.
And yeah, I figured that the proportions are shown “correctly” — my point was that the “spiffy” presentation made the result hard to observe. Since the point of graphics is to make information easier to digest, that is another strike against the chart.
Face it, if you want to put this information in a graphic you use a bar graph. Much easier to understand and not dumb.
But I really don’t know why Waxx is having a temper tantrum about this. The last man standing against the chart Nazi hordes?
I presume that Waxx purportedly believes in an ideology that upholds self-reliance and objective standards of excellence and finds identity politics and victim-mongering disagreeable. And yet in this thread he is whining about the “chart czars” that are oppressing a local TV news station (because it so fashionable!), and in the Swiss thread he’s talking about the “mancession.” Funny that.
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November 30, 2009, 9:55 pmJackOfClubs says:
Normalizing to 100% would not have saved this report since the data overlap. At least half of the Republicans who had favorable views of Romney also had favorable views of Palin and more than a third favored Huckabee.
What they needed here was a bar chart or maybe a Venn diagram, though in the latter case they would need to show how big the overlaps were and I don’t think they actually captured that data. At least it wasn’t published in the summary that Benjamin R. George links to above.
Incidentally, Fox Chicago got the source wrong as well: Opinions Dynamic rather than Opinion Dynamics.
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November 30, 2009, 10:00 pmRyan Waxx says:
Henceforth, all criticism of LN is considered “whining”. Especially if you’re laughing at him. He doesn’t like that. Too many bad memories of the high school shower room, probably.
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November 30, 2009, 10:01 pmrpt says:
Ryan:
Is this like the “Laugher Curve” baked into a pie?
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November 30, 2009, 10:10 pmRyan Waxx says:
Maybe. At least it’s more intelligent then calling for Venn diagrams on the nightly news.
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November 30, 2009, 10:14 pmegd says:
So Fox screwed up, not really surprising.
Although I find it interesting that EV decided to report on this interesting news story, yet somehow he completely missed CNN’s manufactured story, and hilarious backpedaling after being called on it.
The more important question is, why does EV feel like he needs to dump on Fox? Trying to reestablish his academic bona fides after too much free market discussions on his blog?
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November 30, 2009, 10:28 pmRyan Waxx says:
Shh!
Don’t you see that the choice of a pie chart over a bar chart is the important thing? Little things like screwing up an entire story from the ground up prove nothing. PROPER CHART CHOICE is where the hard news is at... Just ask RN.
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November 30, 2009, 10:38 pmLN says:
Ryan, are you conceding that the chart is dumb? Because you spent a lot of time arguing that it wasn’t.
As for me, I was just struck by how someone wrong about every political issue could also be wrong about something as simple as a pie chart... it’s just funny. If you want to come up with an actual example of another pie chart in which the size of the whole pie has absolutely no meaning, please go ahead, I will be very impressed. In the meantime, well, I guess you could find a way to use CNN to bolster your “argument” here. It is rather relevant.
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November 30, 2009, 10:48 pmJoe says:
Ryan, stop it, you’re embarrassing yourself
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November 30, 2009, 11:07 pmSteel Phoenix says:
Yeah, everyone knows that a circle has 360°, so where did the other 167% go?
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December 1, 2009, 12:11 amanomdebus says:
I agree that the pie chart was the wrong choice of chart, but I don’t see how it is manipulation.
On one hand if you did a pie chart with proportions of items with their gross number (instead of percent of total number), then that chart would not add up to 100 either(in most cases). This is a little more confusing since the gross numbers are themselves percentages.
On the other hand, the chart is measuring what is neither rivalrous nor complete. So, it doesn’t make sense to set them as proportions of a whole. Also, they should mention what that percentage is measured, both in chart and in the commentary.
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December 1, 2009, 1:30 amwolfefan says:
Hi Ryan —
Thanks for your response. As you note, the chart is potentially confusing without the report. But for a TV viewer, the report wasn’t available. That’s why I don’t like the chart.
But you do, and that’s okay.
I actually like to sing “Kum-ba-ya.” Takes me back to Camp Sugar Grove near Pleasant Hill, Ohio. :)
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December 1, 2009, 1:35 amNickM says:
Imagine a pie chart of “jobs saved or created”.
Nick
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December 1, 2009, 3:34 amD.O. says:
Seeing that pie chart i instantly remembered a map shown on CNN a few years ago where Czechoslovakia label was prominently written inside the outline of Switzerland. There is no logical connection, just comparable laugh factor, but i would like to read some defenses of that map. They must be fun too.
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December 1, 2009, 3:42 amTweets that mention The Volokh Conspiracy » Blog Archive » This Pie Goes To 193% -- Topsy.com says:
[...] This post was mentioned on Twitter by andrew and Eugene Volokh, Eugene Volokh. Eugene Volokh said: This Pie Goes To 193%: Pie chart zaniness from Fox Chicago News, reported by David DiSalvo (True/Slant). UPDATE.. http://bit.ly/7Cim9C [...]
Guy says:
I don’t think anyone (certainly not me) is saying this is intentional manipulation, it’s just a really dumb mistake by someone who doesn’t know how to make charts appropriately. It is misleading to represent it in the form of a pie chart, as it creates the impression that they asked each person who they favored most and were only allowed to pick one, rather than what apparently did happen, which is they asked each person whether they approved/disapproved of which candidate. A bar graph would be the far more appropriate representation. I also think it’s ironic that you accuse people of having a knee-jerk reaction to bash Fox when, based on your past comments, I think it’s far more likely that you are having a knee-jerk reaction to defend Fox and accuse other of having bias. (Even though this is just a local Fox affiliate– a kind of confusion that happens to be one of my pet peeves).
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December 1, 2009, 6:10 amEast says:
I find myself agreeing with Ryan Waxx, but only because I want to live in a world where I can have a 193% slice of pie.
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December 1, 2009, 6:42 amFantasiaWHT says:
I was waiting for “Percentages do not add up to 100% because of rounding”
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December 1, 2009, 7:49 amCountDuckula says:
I think Ryan Waxx delivered 193% of my comedy allotment for today.
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December 1, 2009, 8:51 amCJColucci says:
When I saw the chart, I eventually figured out what it must have meant, but it took a while and I’m sure a number of viewers didn’t figure it out. And only later was I able to confirm that it actually meant what I thought it did. I don’t claim that the chart was manipulative, or a violation of some principle. It just didn’t work well.
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December 1, 2009, 11:14 amDavid Nieporent says:
Stop bashing Ryan. He is simply demonstrating that there’s a difference between knowledge gained from education and “knowledge” gained from Googling.
Wait, he’s serious?
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December 1, 2009, 11:54 amDavid Nieporent says:
Actually, you know what they needed here? (*) A text chart:
Palin: 70%
Huckabee: 63%
Romney: 60%
That’s it. No charts, graphs, or diagrams. Graphics are supposed to convey additional information that is hard to see with just text. With only three numbers, the picture doesn’t add any information anyway. (I agree that a Venn Diagram would be appropriate if they actually were trying to show how the candidates’ support overlaps.)
(*) I leave out the real response: nothing, since the response to the question is actually stupid infotainment of no news value.
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December 1, 2009, 12:02 pmtroll_dc2 says:
David Nieporent is my candidate for winner of the thread.
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December 1, 2009, 12:08 pmrmd says:
Dude, chill out. It was supposed to be a comic relief post after all the heavy-duty climate stuff. Have a brownie; I made ‘em myself.
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December 1, 2009, 12:23 pmKen says:
Funny.
But not as funny as the time Fox put up a graphic with Frederick Douglass to illustrate a discussion of the Lincoln-Douglas debates.
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December 1, 2009, 12:39 pmJon Peltier says:
Doesn’t this say what you think none of them say?
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December 1, 2009, 12:46 pmDavid Schwartz says:
You guys are incorrect the whole is meaningless. The whole is perfectly meaningful. 193% is the total number of support ‘votes’ cast for the three candidates mentioned, normalized to 100% being the maximum an individual candidate can get. There is no reason a pie chart must represent slivers of a fixed whole, though this is the most common use and the one pie charts are most suited to.
An example of a pie chart where the total actually is meaningless might be a pie chart with one wedge for each of your three call centers and the size of the wedge showing how many minutes each center’s average call length is.
This graphic was bad because it confused people and poorly presented the information it did have. However, it did not present numbers that were actually incorrect nor did it violate some fundamental mathematical rule that pie charts must follow.
I think this simply means that the proportions of the number each wedge of the pie chart represents follows the visual proportions of the wedge sizes. The “whole” in one case being the whole chart and the other case the sum of the numbers, whatever it may be.
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December 1, 2009, 6:04 pmDavid Nieporent says:
193% of what?
No reason except that this is the purpose of a pie chart. If you want it to represent something else, you don’t use a pie chart.
Yes, that would be another example of a situation in which nobody who understood what they were doing would use a pie chart, because it’s a misuse of the form.
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December 1, 2009, 7:00 pmJon Peltier says:
I guess I could see a second grader making this mistake.
The only valid use for a pie chart is to represent fractions of a whole. Not average minutes at various call centers, not approval ratings where people may approve of multiple public figures.
You could use a pie chart for one of these people, and plot a wedge for approve, disapprove, and neutral. Those would add to 100%. Or you could have a pie chart for data that showed how many voted for each candidate, where each person voting got one vote. You could use a pie chart, but I wouldn’t. Not unless there were only two pie segments, or three if the third were much smaller than the other two.
People who study human cognition, that is, the ability of a human to look at an object and understand it, will say that pie charts are one of the worst ways to try to represent data. Even for parts of a whole, charts with bars next to each other are better than bars stacked up to a height of 100%.
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December 1, 2009, 7:52 pmDavid Schwartz says:
193% of the people who cast support votes. That is, the total number of support votes cast for the three candidates of interest was 193% of the people who cast them. (And, of course, the confusing number didn’t come from them. It’s the number you got when you chose to total things that don’t make very much sense to total.)
Is that a particularly good way to represent the data? No. Is it fundamentally wrong? No.
Consider, for example, a bar chart showing the number of voters who showed up in each of several counties compared to how many showed up at the previous election. Some will be less than 100% (fewer voters this election) some will be more than 100% (more voters this election). They now say “the average over the 10 counties was 120%”.
That’s not a meaningless number. It’s quite clear what it means. But it’s not 120% of anything. (Each percentage is of the voters in the previous election in that county but when you average percentages of different wholes, the result is still a percentage but no longer “of” anything in particular.)
All they did wrong was make their graphic confusing.
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December 2, 2009, 2:35 amJon Peltier says:
What? It’s not that at all. The three candidates have support of 70, 63, and 60% of the people polled. Are you saying then that 193% of the people polled did were combined into the chart? No, there’s a lot of overlap between the 70, 63, and 60%. I’ll bet nearly everyone who supported Romney also supported Palin. When there is overlap like this, a pie chart is not confusing, it is stupid, and it is wrong.
You want to make the pie chart even better? Include Newt Gingrich, who had a 58% approval rating. Now the chart adds to 251%.
Suppose there are ten families. 6 have dogs, and 5 have cats (and 3 of the families have dogs and cats). You’re argument says that the proportion of families with pets is 110%, when it’s really 80%.
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December 2, 2009, 7:27 amDavid Schwartz says:
Jon: One figure can be 193% of another, really. The number of cars on the road in 2008 can be 130% of the number of cars on the road in 1998. That doesn’t mean every car on the road in 1998 must be on the road in 2008 and then some.
The total support votes cast for the candidates of interest was 193% of the number of people casting such votes.
Or, here’s another way to do it. You get 53 people in a room. You ask then each to give you all their nickels. You get 92 nickels. The number of nickels you got can accurately be described as 173% of the number of people in the room. That doesn’t mean there are more people, just more nickels.
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December 2, 2009, 11:04 amJon Peltier says:
David -
One figure can be 193% of another. Your car example is a good one. The number of dogs in my family pets example is 120% the number of cats. Both of these make sense.
If you want to use your nickel example to say that each person has an average of 1.73 nickels, well, mathematically is makes sense, but this information is less useful than, say, the change in the number of cars on the road.
What does this even mean? So you want to say that the average person polled supported 1.93 of the candidates? Totally nonsensical in a pie chart, and not relevant in a rational discussion.
The approval of one candidate is not independent of approval of the others. Someone in favor of Palin is more likely to be in favor of the others than someone who disapproves of Palin. 193% is a silly number derived in a silly way by someone who doesn’t understand arithmetic, proportions, or charts.
If 60% of the people in my family has a pair of blue jeans and 80% has a pair of black jeans, do 140% of us have jeans?
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December 2, 2009, 12:14 pmDavid Schwartz says:
Jon Peltier: I agree, that number is not very meaningful. That’s why Fox didn’t include it. But it is simply incorrect to say that the percentages shown in the chart are not percentages of anything nor is it correct to say that the total somehow is not a percentage.
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December 2, 2009, 9:25 pmJon Peltier says:
I did not ever say the percentages shown in the chart were not percentages of anything. They are meaningful as percentages of respondents who have a certain opinion.
In the context of a pie chart, the percentages are absolutely meaningless. I wrote about a better visualization approach in I Keep Saying, Use Bar Charts, Not Pies.
The total is a percentage, sure, but completely meaningless.
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December 2, 2009, 9:31 pm