Economists Do It With Models

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Class Warfare Or Omitted Variables? You Be The Judge…

July 26th, 2016 · No Comments
Causal Friday

Causal Friday came early this week…

Airplane Design Brings Out the Class Warfare in Us All

Air rage is often blamed on overcrowded flights and postage stamp-size seats, but researchers Michael Norton and Katherine A. DeCelles find another culprit: resentment toward passengers in first class.

Source: HBS Working Knowledge

This paper has been talked about in the media quite a bit recently, and, if true, I find the conclusion to be one of the more depressing things about human nature. Given the focus that society has placed on income inequality rather than income trajectory in a more absolute sense, I do find the conclusion plausible…and that’s before I even rustle up the study that shows people would rather make less money than more money if it meant that they made more money than their neighbors. These attitudes are really not helpful for society, since there is a very clear “pull me up by tearing someone else down” dynamic to them.

Luckily for my view of humanity, the paper referenced above appears to suffer from a number of shortcomings. Most of them are summarized here, but I would like to point out an even simpler issue. Essentially, the study establishes a correlation between the existence of a first-class cabin and disruptive incidents when controlling for, *consults paper*, economy seats, first-class seats, economy seat width, economy seat pitch, first-class seat width, flight distance, flight delay, cabin area, international flight, presence of a first class, and a front-boarding process. What is not controlled for, however, is airline (i.e. there are no airline fixed effects)- statistically, this is probably due to high correlation with the other explanatory variables, though it could have also just been an oversight. This presents a problem, since some airlines, as a blanket policy, don’t have first-class cabins (Southwest and most of Jetblue, for example). If such airlines also manage to be customer-service-oriented enough as to not enrage people on dimensions other than those controlled for in the study, it would look like it was the existence of first class that matters and not the nuobserved variation among airlines in how they treat their passengers. (Similarly, there could be a feature of the front-boarding process unrelated to dragging passengers through the first-class cabin that could be making them cranky.) In other words, it’s possible to read this result as “airlines such as Jetblue are more likely to not have enraged passengers, not by forgoing a first-class cabin but by not completely treating people like cattle.” Though Spirit also doesn’t have a first-class cabin, so what do I know*…

* suggests perhaps it is selection of people to airlines that matters, and Spirit passengers are the most tolerant humans in existence, at least in the moment. 🙂

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On Peer-Reviewing Peer Review, Roland Fryer Edition…

July 25th, 2016 · No Comments
Uncategorizable

So this is a thing…

Was This Study Even Peer-Reviewed?
How journalists should write about unpublished scientific research.

Amid the nightmare of the past three weeks, with black men being shot by cops, and then black men shooting cops, the New York Times ran a surprising front-page headline…

Source: slate.com


This raises some interesting points regarding academic publishing. It is generally true that research has been more professionally vetted by the time it is published in a peer-reviewed journal, but it is also true that most research has been presented in seminars, etc. before reaching working paper status, and these environments provide opportunities for vetting, feedback, objection, and so on as well. From a logistical perspective, it’s hard to ignore how long the academic publishing timeline is (often measured in years not months), which means that a lot of research would be somewhat stale before it achieved peer-reviewed status. (Personally, I feel like fixing this process needs to be made a priority.)

On another note, however, I think a number of the criticisms of the study are brought up as caveats in the paper itself, so it’s not particularly fair to write as though the author has tried to hide all weaknesses of the data. Working papers are generally more or less at the stage where they are submitted to journals, so they tend to anticipate reviewer concerns and objections.

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June 7th, 2016 · No Comments
Econ 101 · Tumblr

http://economistsdoitwithmodels.tumblr.com/post/145533393640/the-efficiency-wage-theory-in-simple-graph-form-i

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Battling Bad Science, One Comedian At A Time…

May 11th, 2016 · 3 Comments
Fun With Data

You didn’t think I was going to miss an opportunity to bring you John Oliver talking about p-hacking, did you?

Unfortunately, i think many well-intentioned researchers do this without even thinking about it- they get a dataset and start poking around with it and then decide to focus on the relationships that appear significant (as opposed to having a- singular- theory to test before exploring the data). This doesn’t sound so bad until you consider that 1 out of 20 spurious correlations is going to look statistically significant at the 5% level, which makes the “looking at a bunch of stuff and writing about what looks interesting” approach inherently questionable.

In related news, a picture really is worth a thousand words.

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May 10th, 2016 · No Comments
Behavioral Econ · Policy · Tumblr

http://economistsdoitwithmodels.tumblr.com/post/144164774580/the-wisdom-to-know-what-inequality-can-be-changed

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Billboard Hot 100 Indicators – Week of 4/2/2016

March 29th, 2016 · No Comments
Billboard · Music Biz

So what does popular music look like this week? You can see the current Billboard Hot 100 chart here, and you can see an overview of this data project here. The basic idea is as follows: below is a set of indicator metrics that help summarize the current state of the industry (or, more specifically, a part thereof) and show how it compares to previous weeks. (At least approximately, you can expect a post with updated data every Monday.)

What are presented here are known as “percentiles against history”- percentiles, you know, like you see with kids’ SAT scores, and against history, in comparison to the same metric at earlier periods in time. For example, an artist concentration index of 57 against a 5-year comparison group means that this week’s chart was more concentrated than 57 percent of the weeks in the last 5 years. (This ensures an interpretable metric between 0 and 100.) You can click on any of the index names to see a description and a graph of the overall weekly time series.


Comparison Group 1 year 3 year 5 year 10 year 2000-present
Artist Concentration 55 79 79 83 90
Song Age 75 78 75 88 92
Chart Entry 12 12 10 11 16
Shakeup 73 61 59 49 64
Predictability 25 32 31 37 36
Female Presence 67 39 30 20 21
Group Presence 20 6 4 2 1
Featured Artist Presence 8 3 2 4 13
Country Presence 47 29 19 37 33
Electronic Presence 2 8 12 45 65
Hip Hop Presence 37 79 85 63 46
Pop Presence 94 79 85 92 95
Rock Presence 16 6 5 2 1
World Presence 0 0 0 0 0

In addition, I’m working on a model that predicts next week’s rank based on a song’s chart history and other basic characteristics. (Yes, I know that a better model would pull in data from a variety of sources, but I’m curious as to how much can be done with this more narrow set of information.) So here are next week’s predictions:


Title Artist This Week Next Week Prediction
work rihanna featuring drake 1 2
love yourself justin bieber 2 3
7 years lukas graham 3 1
stressed out twenty one pilots 4 7
my house flo rida 5 8
pillowtalk zayn 6 5
me, myself & i g-eazy x bebe rexha 7 12
sorry justin bieber 8 10
cake by the ocean dnce 9 10
dangerous woman ariana grande 10
i took a pill in ibiza mike posner 11 10
no meghan trainor 12
work from home fifth harmony featuring ty dolla $ign 13 10
one call away charlie puth 14 14
hands to myself selena gomez 15 17
hello adele 16 20
roses the chainsmokers featuring rozes 17 21
2 phones kevin gates 18 17
never forget you zara larsson & mnek 19 16
stitches shawn mendes 20 28
don’t bryson tiller 21 25
down in the dm yo gotti featuring nicki minaj 22 25
youth troye sivan 23 16
jumpman drake & future 24 29
the hills the weeknd 25 34
middle dj snake featuring bipolar sunshine 26 24
oui jeremih 27 26
hotline bling drake 28 36
back to sleep chris brown 29 33
exchange bryson tiller 30 32
summer sixteen drake 31 34
you should be here cole swindell 32 31
panda desiigner 33 25
when we were young adele 34 39
low life future featuring the weeknd 35 32
what do you mean? justin bieber 36 43
say it tory lanez 37 42
let it go james bay 38 35
here alessia cara 39 48
679 fetty wap featuring remy boyz 40 50
hide away daya 41 47
came here to forget blake shelton 42
die a happy man thomas rhett 43 49
drunk on your love brett eldredge 44 43
same old love selena gomez 45 55
like i’m gonna lose you meghan trainor featuring john legend 46 56
in the night the weeknd 47 54
ex’s & oh’s elle king 48 58
white iverson post malone 49 57
can’t feel my face the weeknd 50 62
sugar robin schulz featuring francesco yates 51 53
beautiful drug zac brown band 52 53
my church maren morris 53 54
don’t let me down the chainsmokers featuring daya 54 49
like i would zayn 55
heartbeat carrie underwood 56 60
best friend young thug 57 60
humble and kind tim mcgraw 58 57
somewhere on a beach dierks bentley 59 58
confession florida georgia line 60 60
stand by you rachel platten 61 67
really really kevin gates 62 62
try everything shakira 63
snapback old dominion 64 63
adventure of a lifetime coldplay 65 73
wild things alessia cara 66 63
i like the sound of that rascal flatts 67 66
think of you chris young duet with cassadee pope 68 68
new romantics taylor swift 69
piece by piece kelly clarkson 70 85
needed me rihanna 71 72
something in the way you move ellie goulding 72 78
the sound of silence disturbed 73 68
cut it o.t. genasis featuring young dolph 74 70
promise kid ink featuring fetty wap 75 71
acquainted the weeknd 76 75
company justin bieber 77
jimmy choo fetty wap 78 79
lost boy ruth b 79 76
t-shirt thomas rhett 80 76
nobody to blame chris stapleton 81 83
i know what you did last summer shawn mendes & camila cabello 82 91
might not belly featuring the weeknd 83 79
might be luke nasty 84 84
home alone tonight luke bryan featuring karen fairchild 85 95
mind reader dustin lynch 86 84
cheap thrills sia featuring sean paul 87 84
little bit of you chase bryant 88 89
backroad song granger smith 89 98
saved ty dolla $ign featuring e-40 90 87
we went randy houser 91 99
that don’t sound like you lee brice 92 90
something new zendaya featuring chris brown 93
head over boots jon pardi 94 91
sorry not sorry bryson tiller 95 94
ride twenty one pilots 96
make me like you gwen stefani 97
light it up major lazer featuring nyla 98
break on me. keith urban 99 101
fast car jonas blue featuring dakota 100

(Predictions are blank for songs that don’t have the last 3 weeks of data.) I also post the predictions versus the actual outcomes, and I will update the algorithm and hopefully get more accurate predictions over time…maybe at some point I can be the 538 for the music industry. =P


Title Artist Prediction Result
work rihanna featuring drake 1 1
love yourself justin bieber 3 2
stressed out twenty one pilots 6 4
my house flo rida 6 5
7 years lukas graham 2 3
pillowtalk zayn 5 6
me, myself & i g-eazy x bebe rexha 9 7
sorry justin bieber 14 8
cake by the ocean dnce 10 9
i took a pill in ibiza mike posner 8 11
no meghan trainor 12
hello adele 19 16
hands to myself selena gomez 14 15
roses the chainsmokers featuring rozes 17 17
one call away charlie puth 15 14
work from home fifth harmony featuring ty dolla $ign 13
stitches shawn mendes 24 20
down in the dm yo gotti featuring nicki minaj 20 22
don’t bryson tiller 22 21
piece by piece kelly clarkson 70
2 phones kevin gates 20 18
never forget you zara larsson & mnek 18 19
jumpman drake & future 28 24
the hills the weeknd 33 25
back to sleep chris brown 26 29
exchange bryson tiller 33 30
hotline bling drake 35 28
when we were young adele 32 34
summer sixteen drake 30 31
say it tory lanez 32 37
middle dj snake featuring bipolar sunshine 27 26
here alessia cara 39 39
oui jeremih 35 27
what do you mean? justin bieber 41 36
same old love selena gomez 43 45
in the night the weeknd 42 47
hide away daya 43 41
you should be here cole swindell 37 32
679 fetty wap featuring remy boyz 49 40
ex’s & oh’s elle king 48 48
die a happy man thomas rhett 46 43
like i’m gonna lose you meghan trainor featuring john legend 52 46
low life future featuring the weeknd 39 35
sugar robin schulz featuring francesco yates 43 51
can’t feel my face the weeknd 56 50
white iverson post malone 53 49
stand by you rachel platten 50 61
heartbeat carrie underwood 50 56
drunk on your love brett eldredge 48 44
let it go james bay 49 38
my church maren morris 50 53
something in the way you move ellie goulding 52 72
adventure of a lifetime coldplay 60 65
came here to forget blake shelton 42
beautiful drug zac brown band 56 52
best friend young thug 59 57
humble and kind tim mcgraw 55 58
youth troye sivan 56 23
really really kevin gates 57 62
confession florida georgia line 59 60
somewhere on a beach dierks bentley 59 59
snapback old dominion 59 64
don’t let me down the chainsmokers featuring daya 57 54
think of you chris young duet with cassadee pope 61 68
backroad song granger smith 66 89
try everything shakira 63
i like the sound of that rascal flatts 66 67
needed me rihanna 68 71
wild things alessia cara 64 66
home alone tonight luke bryan featuring karen fairchild 77 85
i know what you did last summer shawn mendes & camila cabello 79 82
panda desiigner 66 33
new romantics taylor swift 69
jimmy choo fetty wap 74 78
we went randy houser 79 91
the sound of silence disturbed 71 73
acquainted the weeknd 78 76
nobody to blame chris stapleton 80 81
untitled 02 l 06.23.2014. kendrick lamar 101
cut it o.t. genasis featuring young dolph 76 74
break on me. keith urban 88 99
might be luke nasty 82 84
american country love song jake owen 101
t-shirt thomas rhett 80
promise kid ink featuring fetty wap 84 75
little bit of you chase bryant 86 88
lost boy ruth b 88 79
mind reader dustin lynch 88 86
company justin bieber 77
untitled 07 l 2014 – 2016 kendrick lamar 101
watch out 2 chainz 92 101
cheap thrills sia featuring sean paul 91 87
that don’t sound like you lee brice 93 92
might not belly featuring the weeknd 91 83
saved ty dolla $ign featuring e-40 95 90
something new zendaya featuring chris brown 93
get ugly jason derulo 101 101
head over boots jon pardi 94
sorry not sorry bryson tiller 101 95
gotta lotta 2 chainz featuring lil wayne 101

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