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Category: math misused

  • Debunking the “Republican Congress Creates Jobs” Chart Or “How To Make Numbers Say Anything You Want”

    This is a companion piece to the previous post, so please read both of them. Here I’m going to lay out the script I had written for debunking the chart I created that asked the question “Does a Republican Congress Create More Jobs?” and then implied with a chart that this was indeed the case. I’ll walk through some process for creating charts and then talk about why I would create a chart that I was just going to debunk.

    I apologize for the similarity to the post where I debunk the Obama stimulus chart. These two scripts were meant to be together.

    <Start Script>

    How to Make Number Say Anything You Want

    Do you want to convince people that your side is right with only the flimsiest proof? Does the idea of tricking people with numbers make you all happy inside? Then come join us as we walk through “How To Use Charts To Say Anything”

    Step 1: Massaging the Data

    The first step is to grab the data that makes your point the best. Let\’s use it to prove that a Democratic Congress is bad for jobs.

    “How can we do such a thing” you ask?

    In the first case, the raw jobs data looks like this

    but the final chart looks like this.

    How did they do that? Was it magic?

    Nope, we simply smoothed the data. The raw data is a little too chaotic and has too many data point to tell the straightforward story that we want. So instead, we\’ll average the monthly data so that we have quarterly data. There… now we have some nice smooth straightforward data

    Step 2: Pick colors that make you look good

    Next, we pick some colors. Let\’s make the Democrats blue dark and bold, give it a bit of an angry feel to it. This is our way of getting the audience to look at the democrats in a harsh way. We could try to soften up on the Republicans more, but too soft of a red would look pink and we don\’t want that.

    Let\’s compare our colors to the Excel defaults:

    Step 3: Do NOT give any context!

    Finally, and this is the most important part, only give information that is helpful.

    Let everyone know that we saw 8 million jobs added to the economy while the Republicans were in charge and make a point to show that we lost 8 million jobs while the Democrats were in charge. But don’t mention that the Republicans took Congress only a year after 9/11 at a time when the job market was particularly low. Otherwise people will think it’s a “Well, they can’t fall off the floor” thing.

    And make sure you don’t mention anything about the real estate market and how the bubble drove the labor market in a way that was clearly unsustainable. We don’t want the viewers to be confused with all these relevant details. We want them to say “Republicans good, Democrats bad”.

    <End Script>

    Everyone here was incredibly kind to put up with my bullshit chart for as long as I left it up without explanation. I\’d like to say unequivocally: My chart is propaganda… just like the Obama administration’s chart. I was trying to use my chart as a visual talking point that said:

    If you have no ethical qualms, data visualizations can be manipulated to say exactly what you want them to say.

    My chart implies that the Republicans were responsible for the jobs growth between 2003 and 2007 and that Democrats were responsible for the drastic decline from 2007 to the present. Let me state plainly, I do not think that is the case.

    But if we just play around with the data the right way, we get what seems to be a clear picture that portrays a correlation and gets on its hands and knees and begs us to draw causation from it. Most people will do exactly that.

    I can spend hours walking patiently through what is wrong with the Obama administration’s chart. Let me recap the high points here:

    • If you look at the data with the context of what President Obama\’s team was hoping the stimulus would do, the power of the chart disappears.
    • If you look at the data with the understanding that they’re charting a first derivative, you realize that we haven’t gained jobs, we’re just losing them more slowly and the power of the chart disappears.
    • If you look at the data with the understanding that they didn’t even start spending the stimulus until the job loss had started slowing down, the power of the chart disappears.
    • If you look at the data in the context of other recessions, you’ll realize that, far from showing a drastic improvement, the numbers represent a devastatingly slow jobs recovery compared to other recoveries and the power of the chart disappears.

    But this kind of explanatory rebuttal would interest those already convinced. The chart I made had a power that an calm explanatory video wouldn’t have. Quite frankly, I hate that this is the case. Like President Obama’s chart, my chart doesn’t teach people anything about economics or lead people to learn important things about unemployment.

    The only valuable thing my chart teaches is that charts can portray accurate data and still be manipulated to coach people along to poor conclusions. The only reason I even put my chart up is because it is the graphical equivalent of drawing out the Obama administration’s argument to its logical conclusion. My chart works with the same data, the same assumptions, and the same implications. And it leads to a completely different conclusion.

    I’ve heard people describe President Obama’s chart as “powerful” and “brilliant”. The popular information visualization blog Flowing Data even tossed it up for public discussion among info viz professionals.

    My point here is that it isn’t brilliant. It’s juvenile. It’s the chart equivalent of a crass political cartoon with a Snidely Whiplash mustache drawn on the bad guys. It’s a design trick imagined by cynical, self-congratulatory children fresh out of graduate school who pat themselves on the back for their ability to fool people who they think are too stupid to know the difference. They think they are special because they can get powerful people to flatter them for their ability to lie.

    But they aren’t special. I can play that same childish game in my free time. The difference if that I want people to know that it’s a trick. They would rather see people fooled.

  • Why Take Math? So Your Ignorance Isn\’t Broadcast Nationwide on the AP Wire

    This is pretty funny. Or horrifying. Depends on how you want to look at it.

    Several days ago, I noted on Twitter that there were a lot of \”saved\” jobs that weren\’t saved at all but actually cost of living increases. About 24 hours after I noted this, there was an Associated Press article about that very phenomena.

    Coincidence? Almost certainly. But I\’ll flatter myself anyway.

    But the laugh riot comes several paragraphs into the article as they look into why Southwest Georgia Community Action Council was able to save 935 jobs with a cost of living increase for only 508 people. The director of the action council said:

    \”she followed the guidelines the Obama administration provided. She said she multiplied the 508 employees by 1.84 — the percentage pay raise they received — and came up with 935 jobs saved.

    \”I would say it\’s confusing at best,\” she said. \”But we followed the instructions we were given.\”

    \”Confusing at best\”? The multiplication of percentages is \”confusing at best\”? It seems obvious to me she should have multiplied 508 people by the amount the increase (.0184) and gotten 9.3. But she forgot that you have to divide the percentage by 100 before you multiply.

    The fact that she had \”saved\” more jobs than there were people in the organization should have been a tip-off. But this is a pretty common problem with people who don\’t have a very good grasp on mathematics… they don\’t recognize obvious mathematical errors, they just plug in the numbers and go with whatever comes out.

    And this, children, is why you pay attention at school. So you don\’t get in the national news for doing something really stupid and then blame it on the instruction manual.

  • Why Take Math? So Your Ignorance Isn't Broadcast Nationwide on the AP Wire

    This is pretty funny. Or horrifying. Depends on how you want to look at it.

    Several days ago, I noted on Twitter that there were a lot of \”saved\” jobs that weren\’t saved at all but actually cost of living increases. About 24 hours after I noted this, there was an Associated Press article about that very phenomena.

    Coincidence? Almost certainly. But I\’ll flatter myself anyway.

    But the laugh riot comes several paragraphs into the article as they look into why Southwest Georgia Community Action Council was able to save 935 jobs with a cost of living increase for only 508 people. The director of the action council said:

    \”she followed the guidelines the Obama administration provided. She said she multiplied the 508 employees by 1.84 — the percentage pay raise they received — and came up with 935 jobs saved.

    \”I would say it\’s confusing at best,\” she said. \”But we followed the instructions we were given.\”

    \”Confusing at best\”? The multiplication of percentages is \”confusing at best\”? It seems obvious to me she should have multiplied 508 people by the amount the increase (.0184) and gotten 9.3. But she forgot that you have to divide the percentage by 100 before you multiply.

    The fact that she had \”saved\” more jobs than there were people in the organization should have been a tip-off. But this is a pretty common problem with people who don\’t have a very good grasp on mathematics… they don\’t recognize obvious mathematical errors, they just plug in the numbers and go with whatever comes out.

    And this, children, is why you pay attention at school. So you don\’t get in the national news for doing something really stupid and then blame it on the instruction manual.

  • Why Take Math? So Your Ignorance Isn\’t Broadcast Nationwide on the AP Wire

    This is pretty funny. Or horrifying. Depends on how you want to look at it.

    Several days ago, I noted on Twitter that there were a lot of \”saved\” jobs that weren\’t saved at all but actually cost of living increases. About 24 hours after I noted this, there was an Associated Press article about that very phenomena.

    Coincidence? Almost certainly. But I\’ll flatter myself anyway.

    But the laugh riot comes several paragraphs into the article as they look into why Southwest Georgia Community Action Council was able to save 935 jobs with a cost of living increase for only 508 people. The director of the action council said:

    \”she followed the guidelines the Obama administration provided. She said she multiplied the 508 employees by 1.84 — the percentage pay raise they received — and came up with 935 jobs saved.

    \”I would say it\’s confusing at best,\” she said. \”But we followed the instructions we were given.\”

    \”Confusing at best\”? The multiplication of percentages is \”confusing at best\”? It seems obvious to me she should have multiplied 508 people by the amount the increase (.0184) and gotten 9.3. But she forgot that you have to divide the percentage by 100 before you multiply.

    The fact that she had \”saved\” more jobs than there were people in the organization should have been a tip-off. But this is a pretty common problem with people who don\’t have a very good grasp on mathematics… they don\’t recognize obvious mathematical errors, they just plug in the numbers and go with whatever comes out.

    And this, children, is why you pay attention at school. So you don\’t get in the national news for doing something really stupid and then blame it on the instruction manual.

  • Why Take Math? So Your Ignorance Isn\’t Broadcast Nationwide on the AP Wire

    This is pretty funny. Or horrifying. Depends on how you want to look at it.

    Several days ago, I noted on Twitter that there were a lot of \”saved\” jobs that weren\’t saved at all but actually cost of living increases. About 24 hours after I noted this, there was an Associated Press article about that very phenomena.

    Coincidence? Almost certainly. But I\’ll flatter myself anyway.

    But the laugh riot comes several paragraphs into the article as they look into why Southwest Georgia Community Action Council was able to save 935 jobs with a cost of living increase for only 508 people. The director of the action council said:

    \”she followed the guidelines the Obama administration provided. She said she multiplied the 508 employees by 1.84 — the percentage pay raise they received — and came up with 935 jobs saved.

    \”I would say it\’s confusing at best,\” she said. \”But we followed the instructions we were given.\”

    \”Confusing at best\”? The multiplication of percentages is \”confusing at best\”? It seems obvious to me she should have multiplied 508 people by the amount the increase (.0184) and gotten 9.3. But she forgot that you have to divide the percentage by 100 before you multiply.

    The fact that she had \”saved\” more jobs than there were people in the organization should have been a tip-off. But this is a pretty common problem with people who don\’t have a very good grasp on mathematics… they don\’t recognize obvious mathematical errors, they just plug in the numbers and go with whatever comes out.

    And this, children, is why you pay attention at school. So you don\’t get in the national news for doing something really stupid and then blame it on the instruction manual.

  • Jumping Into Visualization Without the Math

    I found this link from Instapundit, so credit where it is due.

    You may have seen this visual of job loss across the country. It maps the job gains and losses in major metro areas across the country and, on the surface it seems pretty cool. Here\’s October 2008.

    \"JobLossOctober2008\"

    As someone who really loves information visualization, I applaud the effort. But it\’s wrong.

    Let\’s take a quick look at the legend. See if you can spot the problem.

    \"JobLossScale\"

    Keen readers will notice the problem… whoever created this visual scaled only the diameter of the circle. The problem with this is what we can see below.

    \"JobLossScaleProblem\"

    Here I took the \”10,000\” circle and duplicated it over 50 times within the \”100,000\” circle. If this visual were an accurate one, we would multiply the 10,000 circle ten times to get 100,000. That\’s just the way these things should work.

    Math Time! (skip if you don\’t care)

    The area of a circle is calculated with the equation:

    \"AreaText\"

    Which means that when they increase the height of the circle by 10, they increase it\’s area by 100. This means that instead of the numbers increasing the way they should, the small numbers end up looking REALLY small and the big ones look absurdly huge.

    End of Math Time

    I\’m not trying to be an a**hole here. The idea behind the visual was a good one. But these things really do need to be accurate. Most people don\’t know how to tell when a visual is in error and they end up with an incorrect impression from a poorly built infographic.

  • Space Junk And Visual Lies

    A little while back, due to a collision between a dead Russian military satellite and a US commercial satellite, there was some noise about space junk because of the potential danger it posed to the International Space Stations and the Shuttle. The image that of space junk that became the icon of the problem is this image (click to enlarge):

    \"SpaceJunkImage\"

    I hate this image. Passionately.

    The reason I hate this image is because it is probably the biggest visual lie I\’ve ever seen. In his book The Visual Display of Quantitative Information\"\", Edward Tufte has a concept called the \”Lie Factor\”. The \”Lie Factor\” judges the extent to which the data and the visual are out of sync.

    Nothing could be more out of sync with reality than this image. While it imagines the appropriate number of objects circling the earth, it completely misrepresents the scale of those objects.

    Space is unimaginably huge. While there are thousands of objects circling the earth, they range in size from a volleyball to a small school bus. If you do the calculations, the objects in this image range in size from Delaware to Tennessee.

    Math Time! (skip if you don\’t care)

    In this image the diameter of the earth is about 1950 pixels. The real diameter of the earth is about 8000 miles. That means that every pixel is a shade over 4 miles.

    The smallest piece of space junk in this image is about 10 pixels wide and 18 pixels tall and the largest one is about 24 pixels wide and 104 pixels tall. That gives the small objects an area of about 3000 square miles (about 30% larger than Delaware) and the large ones an area of 41,000 square miles (a shade smaller than Tennessee).

    End of Math Time

    To give an example of this exaggeration, let\’s look at Angelina Jolie. (How\’s that for a non sequitur?) Jolie has a freckle (beauty mark, mole, whatever) above her right eye.

    \"JolieFreckle\"

    Let\’s say we\’re concerned about people getting skin cancer, so we want to make a shocking graphic that we hope will help people remember to monitor skin markings for signs of melanoma. If we lied visually as much as the space junk photo, we would change a picture of Angelina Jolie from:

    \"JolieNormal\"

    to

    \"JolieFreckleExaggerated\"

    Imagine the Photoshop is done a shade better than I can do. The intention to do good and get people to realize the severity of melanoma is all well and good, but it doesn\’t justify lying to people.

    Granted, the space junk image holds the disclaimer that it is \”an artists impression\”. But that isn\’t how people read these kinds of things and anyone who believes otherwise is, quite frankly, lying to themselves about the realities of human perception and belief. People see these images and they expect that they match reality in some way. Do a search for \”space junk\” to find out how many otherwise intelligent people have accepted this image as reality without a breath to admit how inaccurate it is.

    This is not to say space junk isn\’t a problem. I would have \”solved\” the problem of visual representation by portraying the space junk as a dot. A single pixel that can clearly indicate position instead of pretending to be a representation of size. Then, I would explain that, even though these objects are very tiny compared to the size of the space they\’re in, this junk moves at thousands of miles an hour… making very small objects insanely dangerous.

    You could effectively compare it to shooting a bullet into the air. A tiny piece of metal in a huge space can be really dangerous. People get that. There is no reason to portray the bullet as a 747.

    I\’m worried that even scientific people either didn\’t recognize this problem or didn\’t feel the need to speak up about it. Even people experienced in infographics didn\’t say anything (see here, and here). (Side Note: I take particular pleasure is smacking down Wired magazine for putting up this graphic without even mentioning that it is an \”artist rendering\”. As a whole, they tend to be smug and irritating in the extent to which they dismiss anyone without technical or scientific expertise. Here they reveal that they are just as susceptible to junk science as the average Joe.)

    There is an extent to which many people in scientific and technical journalism are content to give people the appropriate impression (\”Space junk is a dangerous problem\”) without providing them with the appropriate information. Or, to put the problem simply, they think the end justifies the means.

    I take the view that truth in data is the highest importance. I\’m frustrated in how lonely it is out here on my high ground.

  • "Real Unemployment" at 16%? Color Me Skeptical

    You may have seen the recent headline \”Real US unemployment rate at 16 pct: Fed official. A snippet:

    \”If one considers the people who would like a job but have stopped looking — so-called discouraged workers — and those who are working fewer hours than they want, the unemployment rate would move from the official 9.4 percent to 16 percent, said Atlanta Fed chief Dennis Lockhart.

    UPDATE: Commentor Tom M. takes note that Mr. Lockhart is probably refering to the U6 numbers and this fact was simply not reported appropriately. He says:

    When economists, such as myself, talk about the “real” unemployment rate, we are usually referring to the U6 unemployment figure, which is the U3 rate (the published/official rate) plus people that are “part time for economic reasons” among other groups.

    If that is the case, it makes most of the rest of what I have to say pretty much void, but I\’ll leave it up anyway. Thanks Tom!

    A little while back, I called \”discouraged workers\” the \”despair numbers\” (basically, they say they want a job, but they aren\’t looking for one).

    My conclusion was that we\’ve always had despair or discouraged workers, so suddenly adding them in now seems like a dishonest tactic to artificially inflate unemployment to some scary level. In good times, we saw unemployment at about 4-5%, so we\’re used to thinking about that range as being good. But if you add the \”discouraged workers\” in those good times, you\’re looking at a \”good\” unemployment rate of about 7-8%.

    As for the \”wants to work more hours\” crowd, I\’m open to considering that group in some way, shape or form, but I don\’t know how to add them in a way that is honest. Frankly, as a small business owner and contractor, I don\’t work as many hours as I would like. But I don\’t go around calling myself \”unemployed\” or even \”underemployed\”.

    If you look at the Bureau of Labor\’s stats on part time workers, you can see that the number has jumped about 3 million in the past year. If we add those workers plus the increase in the \”discouraged workers\” (about 1 million), we get a rate a little over 12%.

    But the problem in my mind is that you can\’t simply add part time workers to the \”unemployed\” list to get any kind of meaningful data. Maybe, for the sake of argumentation, you could could cast an involuntary part time worker as half a worker. Then the unemployment rate is a shade over 11%. This is, I think, a not-unreasonable number to use, given that it shaves off the standard number of \”discouraged workers\” and uses a dampening variable to account for the fact that part-time workers aren\’t really \”unemployed\”, but \”underemployed\”.

    But I could be easily convinced that crunching the numbers in a new and interesting way is basically statistical cheating and we should just use the standard definitions.

    Overall, I\’m really uncomfortable with the whole \”let\’s crunch the numbers so the situation look really terrible\” methodology because all it does is try to cast the current situation in a bad light by changing the metric. But you can\’t use one metric in the good times and another metric in the bad times.

    As such, I think the 16% number is really more of a scare tactic than anything else.

  • \”Real Unemployment\” at 16%? Color Me Skeptical

    You may have seen the recent headline \”Real US unemployment rate at 16 pct: Fed official. A snippet:

    \”If one considers the people who would like a job but have stopped looking — so-called discouraged workers — and those who are working fewer hours than they want, the unemployment rate would move from the official 9.4 percent to 16 percent, said Atlanta Fed chief Dennis Lockhart.

    UPDATE: Commentor Tom M. takes note that Mr. Lockhart is probably refering to the U6 numbers and this fact was simply not reported appropriately. He says:

    When economists, such as myself, talk about the “real” unemployment rate, we are usually referring to the U6 unemployment figure, which is the U3 rate (the published/official rate) plus people that are “part time for economic reasons” among other groups.

    If that is the case, it makes most of the rest of what I have to say pretty much void, but I\’ll leave it up anyway. Thanks Tom!

    A little while back, I called \”discouraged workers\” the \”despair numbers\” (basically, they say they want a job, but they aren\’t looking for one).

    My conclusion was that we\’ve always had despair or discouraged workers, so suddenly adding them in now seems like a dishonest tactic to artificially inflate unemployment to some scary level. In good times, we saw unemployment at about 4-5%, so we\’re used to thinking about that range as being good. But if you add the \”discouraged workers\” in those good times, you\’re looking at a \”good\” unemployment rate of about 7-8%.

    As for the \”wants to work more hours\” crowd, I\’m open to considering that group in some way, shape or form, but I don\’t know how to add them in a way that is honest. Frankly, as a small business owner and contractor, I don\’t work as many hours as I would like. But I don\’t go around calling myself \”unemployed\” or even \”underemployed\”.

    If you look at the Bureau of Labor\’s stats on part time workers, you can see that the number has jumped about 3 million in the past year. If we add those workers plus the increase in the \”discouraged workers\” (about 1 million), we get a rate a little over 12%.

    But the problem in my mind is that you can\’t simply add part time workers to the \”unemployed\” list to get any kind of meaningful data. Maybe, for the sake of argumentation, you could could cast an involuntary part time worker as half a worker. Then the unemployment rate is a shade over 11%. This is, I think, a not-unreasonable number to use, given that it shaves off the standard number of \”discouraged workers\” and uses a dampening variable to account for the fact that part-time workers aren\’t really \”unemployed\”, but \”underemployed\”.

    But I could be easily convinced that crunching the numbers in a new and interesting way is basically statistical cheating and we should just use the standard definitions.

    Overall, I\’m really uncomfortable with the whole \”let\’s crunch the numbers so the situation look really terrible\” methodology because all it does is try to cast the current situation in a bad light by changing the metric. But you can\’t use one metric in the good times and another metric in the bad times.

    As such, I think the 16% number is really more of a scare tactic than anything else.

  • \”Real Unemployment\” at 16%? Color Me Skeptical

    You may have seen the recent headline \”Real US unemployment rate at 16 pct: Fed official. A snippet:

    \”If one considers the people who would like a job but have stopped looking — so-called discouraged workers — and those who are working fewer hours than they want, the unemployment rate would move from the official 9.4 percent to 16 percent, said Atlanta Fed chief Dennis Lockhart.

    UPDATE: Commentor Tom M. takes note that Mr. Lockhart is probably refering to the U6 numbers and this fact was simply not reported appropriately. He says:

    When economists, such as myself, talk about the “real” unemployment rate, we are usually referring to the U6 unemployment figure, which is the U3 rate (the published/official rate) plus people that are “part time for economic reasons” among other groups.

    If that is the case, it makes most of the rest of what I have to say pretty much void, but I\’ll leave it up anyway. Thanks Tom!

    A little while back, I called \”discouraged workers\” the \”despair numbers\” (basically, they say they want a job, but they aren\’t looking for one).

    My conclusion was that we\’ve always had despair or discouraged workers, so suddenly adding them in now seems like a dishonest tactic to artificially inflate unemployment to some scary level. In good times, we saw unemployment at about 4-5%, so we\’re used to thinking about that range as being good. But if you add the \”discouraged workers\” in those good times, you\’re looking at a \”good\” unemployment rate of about 7-8%.

    As for the \”wants to work more hours\” crowd, I\’m open to considering that group in some way, shape or form, but I don\’t know how to add them in a way that is honest. Frankly, as a small business owner and contractor, I don\’t work as many hours as I would like. But I don\’t go around calling myself \”unemployed\” or even \”underemployed\”.

    If you look at the Bureau of Labor\’s stats on part time workers, you can see that the number has jumped about 3 million in the past year. If we add those workers plus the increase in the \”discouraged workers\” (about 1 million), we get a rate a little over 12%.

    But the problem in my mind is that you can\’t simply add part time workers to the \”unemployed\” list to get any kind of meaningful data. Maybe, for the sake of argumentation, you could could cast an involuntary part time worker as half a worker. Then the unemployment rate is a shade over 11%. This is, I think, a not-unreasonable number to use, given that it shaves off the standard number of \”discouraged workers\” and uses a dampening variable to account for the fact that part-time workers aren\’t really \”unemployed\”, but \”underemployed\”.

    But I could be easily convinced that crunching the numbers in a new and interesting way is basically statistical cheating and we should just use the standard definitions.

    Overall, I\’m really uncomfortable with the whole \”let\’s crunch the numbers so the situation look really terrible\” methodology because all it does is try to cast the current situation in a bad light by changing the metric. But you can\’t use one metric in the good times and another metric in the bad times.

    As such, I think the 16% number is really more of a scare tactic than anything else.