12:14
TEDGlobal 2012

Keith Chen: Could your language affect your ability to save money?

キース・チェン:言語が貯蓄能力に与える影響

Filmed:

経済学者が言語学の分野から学べることとは?行動経済学者キース・チェンが自身の研究から見出した興味深いパターンを紹介します。未来の概念のない言語("It will rain tomorrow" ではなく "It rain tomorrow" が許容される言語)と高い貯蓄率の間には強い相関関係があるのです。

- Behavioral economist
Keith Chen's research suggests that the language you speak may impact the way you think about your future. Full bio

The global economic financial crisis has reignited public interest
世界的な金融危機を受けて
また関心を集めていることがあります
00:16
in something that's actually one of the oldest questions in economics,
経済学においては最も古く
少なくとも ―
00:20
dating back to at least before Adam Smith.
アダム・スミス以前から続く問いです
00:24
And that is, why is it that countries with seemingly similar economies and institutions
「経済活動や制度が類似する国々で
貯蓄行動が大いに異なるのは何故か」
00:27
can display radically different savings behavior?
「経済活動や制度が類似する国々で
貯蓄行動が大いに異なるのは何故か」
00:32
Now, many brilliant economists have spent their entire lives working on this question,
聡明な経済学者たちが一生をかけ
答えを追求してきました
00:35
and as a field we've made a tremendous amount of headway
その甲斐あって
議論は大きく前進してきましたし
00:40
and we understand a lot about this.
多くのことが明らかになりました
00:43
What I'm here to talk with you about today is an intriguing new hypothesis
今日ご紹介するのは
私が研究している新たな仮説と
00:46
and some surprisingly powerful new findings that I've been working on
言語の構造と
貯蓄傾向の関連性についての
00:49
about the link between the structure of the language you speak
言語の構造と
貯蓄傾向の関連性についての
00:53
and how you find yourself with the propensity to save.
驚くほど大きな新発見です
00:58
Let me tell you a little bit about savings rates, a little bit about language,
貯蓄率や言語について
簡単に説明した後
01:02
and then I'll draw that connection.
その 関連性を紐解いていきます
01:05
Let's start by thinking about the member countries of the OECD,
まずは OECD
経済協力開発機構の ―
01:08
or the Organization of Economic Cooperation and Development.
加盟国について考えてみましょう
01:12
OECD countries, by and large, you should think about these
OECD諸国は概して
裕福な先進工業国と言えるでしょう
01:16
as the richest, most industrialized countries in the world.
OECD諸国は概して
裕福な先進工業国と言えるでしょう
01:20
And by joining the OECD, they were affirming a common commitment
また OECDに加盟する以上
民主主義や自由市場 ―
01:22
to democracy, open markets and free trade.
自由貿易に取り組むという
意思を表明しています
01:26
Despite all of these similarities, we see huge differences in savings behavior.
こうした共通点はありますが
貯蓄傾向は大きく異なっています
01:30
So all the way over on the left of this graph,
このグラフの左の方をご覧いただくと
01:34
what you see is many OECD countries saving over a quarter of their GDP every year,
多くのOECD諸国では毎年
GDPの4分の1以上を貯蓄しています
01:37
and some OECD countries saving over a third of their GDP per year.
3分の1以上を
貯蓄に回している国もあります
01:42
Holding down the right flank of the OECD, all the way on the other side, is Greece.
反対側を見ていくと
右端はギリシャです
01:46
And what you can see is that over the last 25 years,
ここ25年以上
ギリシャの貯蓄率は
01:51
Greece has barely managed to save more than 10 percent of their GDP.
辛うじてGDPの10%を越える程度で
推移してます
01:54
It should be noted, of course, that the United States and the U.K. are the next in line.
もちろんアメリカとイギリスが
そのすぐ隣にいることも見逃せません
01:58
Now that we see these huge differences in savings rates,
さて こうした貯蓄率における違いに
02:05
how is it possible that language might have something to do with these differences?
言語が関係している可能性が
あるのでしょうか
02:08
Let me tell you a little bit about how languages fundamentally differ.
言語間には根本的な相違があり ―
02:11
Linguists and cognitive scientists have been exploring this question for many years now.
その相違点について 言語学者や
認知科学者が研究を重ねてきました
02:15
And then I'll draw the connection between these two behaviors.
このことが後で貯蓄の話に
関連してきます
02:20
Many of you have probably already noticed that I'm Chinese.
お気づきかと思いますが
私は中国人です
02:25
I grew up in the Midwest of the United States.
アメリカの中西部で育ちました
02:27
And something I realized quite early on
幼少期に
あることに気付いたんです
02:30
was that the Chinese language forced me to speak about and --
中国語で家族のことを話そうとすると
02:33
in fact, more fundamentally than that --
そもそも思考の段階から
02:36
ever so slightly forced me to think about family in very different ways.
英語とは違うのだということです
02:39
Now, how might that be? Let me give you an example.
具体的な例を挙げますね
02:43
Suppose I were talking with you and I was introducing you to my uncle.
例えば 皆さんを私の「おじ」に
紹介するとしましょう
02:45
You understood exactly what I just said in English.
英語では "uncle" で
問題ありませんね
02:50
If we were speaking Mandarin Chinese with each other, though,
しかし これが中国語だと
02:53
I wouldn't have that luxury.
そう簡単には済みません
02:56
I wouldn't have been able to convey so little information.
情報が足りないのです
02:58
What my language would have forced me to do,
中国語では「おじ」に
03:00
instead of just telling you, "This is my uncle,"
膨大な情報を付与しなければ
03:03
is to tell you a tremendous amount of additional information.
何を言っているか伝わらないのです
03:05
My language would force me to tell you
「おじ」と言っても
03:08
whether or not this was an uncle on my mother's side or my father's side,
それが母方なのか 父方なのか
03:10
whether this was an uncle by marriage or by birth,
血縁なのか 姻戚なのか
03:13
and if this man was my father's brother,
父方であれば
03:16
whether he was older than or younger than my father.
父の兄なのか 弟なのか
03:19
All of this information is obligatory. Chinese doesn't let me ignore it.
これらは全て中国語では
無視できない必須項目です
03:21
And in fact, if I want to speak correctly,
中国語で正確に話そうとすると
03:26
Chinese forces me to constantly think about it.
このような事を
考えざるを得ないのです
03:28
Now, that fascinated me endlessly as a child,
私はこういうことで
延々と楽しめる子でしたが
03:31
but what fascinates me even more today as an economist
今日 経済学者として
私が心をつかまれるのは
03:35
is that some of these same differences carry through to how languages speak about time.
「時」についても
言語間で同様の相違があるという点です
03:38
So for example, if I'm speaking in English, I have to speak grammatically differently
例えば 英語を話す場合には
文法に違いが出ます
03:43
if I'm talking about past rain, "It rained yesterday,"
過去なら
"It rained yesterday"
03:48
current rain, "It is raining now,"
現在ならば
"It is raining now"
03:50
or future rain, "It will rain tomorrow."
未来は
"It will rain tomorrow"
03:53
Notice that English requires a lot more information with respect to the timing of events.
英語では事象のタイミングについて
情報が不可欠です
03:55
Why? Because I have to consider that
いつ言うかによって
04:00
and I have to modify what I'm saying to say, "It will rain," or "It's going to rain."
未来形に変える必要が出てくるのです
04:02
It's simply not permissible in English to say, "It rain tomorrow."
"It rain tomorrow" は
英語では許されません
04:07
In contrast to that, that's almost exactly what you would say in Chinese.
ところが中国語では
それでいいのです
04:11
A Chinese speaker can basically say something
英語では奇妙でも
04:15
that sounds very strange to an English speaker's ears.
中国語なら大丈夫です
04:17
They can say, "Yesterday it rain," "Now it rain," "Tomorrow it rain."
過去でも現在でも未来でも
"It rain" と言って構いません
04:20
In some deep sense, Chinese doesn't divide up the time spectrum
つまり中国語には
英語のような時制の区切りがないのです
04:24
in the same way that English forces us to constantly do in order to speak correctly.
つまり中国語には
英語のような時制の区切りがないのです
04:28
Is this difference in languages
英語と中国語の関係が
特別に薄いせいでしょうか?
04:35
only between very, very distantly related languages, like English and Chinese?
英語と中国語の関係が
特別に薄いせいでしょうか?
04:36
Actually, no.
違います
04:40
So many of you know, in this room, that English is a Germanic language.
ご存じのとおり
英語はゲルマン語派ですが
04:41
What you may not have realized is that English is actually an outlier.
実は英語には例外的な特徴があります
04:45
It is the only Germanic language that requires this.
ゲルマン語派で時制があるのは
英語だけです
04:49
For example, most other Germanic language speakers
英語以外のゲルマン語派では
04:52
feel completely comfortable talking about rain tomorrow
明日の雨について
"Morgen regnet es" つまり ―
04:55
by saying, "Morgen regnet es,"
明日の雨について
"Morgen regnet es" つまり ―
04:58
quite literally to an English ear, "It rain tomorrow."
"It rain tomorrow" と言って
差し支えありません
05:00
This led me, as a behavioral economist, to an intriguing hypothesis.
行動経済学者である私は
ある面白い仮説を思いつきました
05:04
Could how you speak about time, could how your language forces you to think about time,
「時」についての捉え方や
言語的な制約が
05:09
affect your propensity to behave across time?
いつの間にか 行動傾向にも
影響しているのではないか?
05:13
You speak English, a futured language.
英語には未来形がありますから
05:17
And what that means is that every time you discuss the future,
皆さんが英語で
将来について話す場合には
05:20
or any kind of a future event,
皆さんが英語で
将来について話す場合には
05:23
grammatically you're forced to cleave that from the present
文法的に現在から切り離す必要があり
05:25
and treat it as if it's something viscerally different.
直感的に遠いものと見なします
05:28
Now suppose that that visceral difference
その遠いものという感覚が
05:31
makes you subtly dissociate the future from the present every time you speak.
英語を使うたびに
現在と将来を切り離していくとすると
05:33
If that's true and it makes the future feel
将来というものは
05:38
like something more distant and more different from the present,
現在から遠く離れたものに感じられ
05:39
that's going to make it harder to save.
貯蓄する気が薄れます
05:42
If, on the other hand, you speak a futureless language,
未来形のない言語では
05:45
the present and the future, you speak about them identically.
現在と未来が一体化しています
05:48
If that subtly nudges you to feel about them identically,
日頃から現在と未来を同一視していると
05:51
that's going to make it easier to save.
貯蓄する気になりやすいのです
05:54
Now this is a fanciful theory.
これは突飛な理論ですが
05:56
I'm a professor, I get paid to have fanciful theories.
私は大学教授なので
これも仕事のうちです
05:59
But how would you actually go about testing such a theory?
実際に理論を検証する方法を考え
06:02
Well, what I did with that was to access the linguistics literature.
言語学の文献を当たりました
06:06
And interestingly enough, there are pockets of futureless language speakers
面白いことに 世界には
未来形のない言語を話す地域が
06:10
situated all over the world.
固まって存在しているのです
06:15
This is a pocket of futureless language speakers in Northern Europe.
北欧のこの地域の言語には
未来の概念がありません
06:16
Interestingly enough, when you start to crank the data,
面白いことに データを見ていくと
06:20
these pockets of futureless language speakers all around the world
未来の概念のない言語を話す人々と
06:23
turn out to be, by and large, some of the world's best savers.
高額の貯蓄を持つ人々が
ほぼ一致することがわかりました
06:26
Just to give you a hint of that,
ヒントはこれです
06:30
let's look back at that OECD graph that we were talking about.
先程のOECDのグラフに
戻りましょう
06:32
What you see is that these bars are systematically taller
貯蓄率の高い国は体系的に
左に寄っています
06:35
and systematically shifted to the left
貯蓄率の高い国は体系的に
左に寄っています
06:38
compared to these bars which are the members of the OECD that speak futured languages.
未来形のある言語を話す国と
比べると こうです
06:40
What is the average difference here?
平均差を求めてみると
06:45
Five percentage points of your GDP saved per year.
貯蓄率の違いは
年間でGDPの5%ずつなので
06:46
Over 25 years that has huge long-run effects on the wealth of your nation.
25年経てば国の資産に
莫大な影響を与えることになります
06:50
Now while these findings are suggestive,
何か関係ありそうな気配ですが
06:54
countries can be different in so many different ways
国ごとの違いというのは
06:57
that it's very, very difficult sometimes to account for all of these possible differences.
内容が多岐に渡りますから
一概には言えません
06:59
What I'm going to show you, though, is something that I've been engaging in for a year,
そこで 私がここ1年
研究してきたことをご紹介します
07:03
which is trying to gather all of the largest datasets
経済学者の持てる
ありとあらゆるデータを駆使し
07:08
that we have access to as economists,
経済学者の持てる
ありとあらゆるデータを駆使し
07:10
and I'm going to try and strip away all of those possible differences,
国ごとの違いを極力排除して
07:12
hoping to get this relationship to break.
相関関係はないと証明したいのですが
07:16
And just in summary, no matter how far I push this, I can't get it to break.
結論から言って
相関を認めざるを得ません
07:18
Let me show you how far you can do that.
検証過程を説明しましょう
07:23
One way to imagine that is I gather large datasets from around the world.
たとえば世界中から
大量のデータを集めます
07:25
So for example, there is the Survey of Health, [Aging] and Retirement in Europe.
「欧州における
健康・加齢・退職の調査」を見ると
07:30
From this dataset you actually learn that retired European families
ヨーロッパの退職者世帯は
このような調査に対し ―
07:33
are extremely patient with survey takers.
非常に忍耐強いことがわかります
07:37
(Laughter)
(笑)
07:40
So imagine that you're a retired household in Belgium and someone comes to your front door.
退職してベルギーに家を構えたとします
誰かが訪ねてきて
07:42
"Excuse me, would you mind if I peruse your stock portfolio?
「すみません
持ち株の明細を見せてもらえませんか?
07:46
Do you happen to know how much your house is worth? Do you mind telling me?
お宅の価格をご存じですか?
教えてもらえます?
07:51
Would you happen to have a hallway that's more than 10 meters long?
10メートル以上の廊下はありますか?
07:54
If you do, would you mind if I timed how long it took you to walk down that hallway?
その廊下をあなたが何秒で歩くか
計ってもいいですか?
07:57
Would you mind squeezing as hard as you can, in your dominant hand, this device
利き手でこの装置を思いっきり
握ってもらえますか?
08:02
so I can measure your grip strength?
握力を測りますから
08:06
How about blowing into this tube so I can measure your lung capacity?"
このチューブに息を吹き込んでください
肺活量を測ります」
08:07
The survey takes over a day.
調査は一日以上を続きます
08:11
(Laughter)
(笑)
08:14
Combine that with a Demographic and Health Survey
さらにUSAIDによる
アフリカの途上国の ―
08:16
collected by USAID in developing countries in Africa, for example,
「人口保健調査」も資料に加えます
08:20
which that survey actually can go so far as to directly measure the HIV status
たとえばナイジェリアの
農村部の世帯のHIV感染状況まで
08:24
of families living in, for example, rural Nigeria.
調べているような資料です
08:29
Combine that with a world value survey,
「世界価値観調査」も使えます
08:32
which measures the political opinions and, fortunately for me, the savings behaviors
世界のあらゆる国で
何百万もの世帯の政治的見解や ―
08:34
of millions of families in hundreds of countries around the world.
ラッキーなことに貯蓄行動まで
調べてある資料です
08:39
Take all of that data, combine it, and this map is what you get.
そうしたデータを全て組み合わせると
こうなります
08:43
What you find is nine countries around the world
ご覧の9カ国では ―
08:47
that have significant native populations
未来形のある言語とない言語
その両方が使われています
08:49
which speak both futureless and futured languages.
未来形のある言語とない言語
その両方が使われています
08:52
And what I'm going to do is form statistical matched pairs
ここから 評価が可能な条件について
08:56
between families that are nearly identical on every dimension that I can measure,
類似するデータを組み合わせて
統計分析のためにペアを作ります
09:00
and then I'm going to explore whether or not the link between language and savings holds
条件を揃えた上で
言語と貯蓄率の間に
09:05
even after controlling for all of these levels.
関連性があるかどうか
調べるというわけです
09:09
What are the characteristics we can control for?
コントロールできる特性は
09:12
Well I'm going to match families on country of birth and residence,
生まれ育った国
09:15
the demographics -- what sex, their age --
性別や年齢などの属性
09:17
their income level within their own country,
各国の基準で見た所得レベル
09:20
their educational achievement, a lot about their family structure.
学歴や家族構成の詳細です
09:22
It turns out there are six different ways to be married in Europe.
欧州では結婚の形態だけで
6種類もありますから
09:25
And most granularly, I break them down by religion
さらに 宗教によって細分化しました
09:28
where there are 72 categories of religions in the world --
世界には72の宗教分類がありますから
09:33
so an extreme level of granularity.
非常に細かくなりますね
09:36
There are 1.4 billion different ways that a family can find itself.
世帯ごとの属性は
全部で14億種類に分類されます
09:38
Now effectively everything I'm going to tell you from now on
ここでは 特性が類似する世帯を抽出し
09:42
is only comparing these basically nearly identical families.
比較した内容だけを抜粋してお話します
09:46
It's getting as close as possible to the thought experiment
ほとんど思考実験のようなものです
09:49
of finding two families both of whom live in Brussels
言語以外の属性が全て共通する ―
09:52
who are identical on every single one of these dimensions,
ブリュッセル在住の2世帯で
09:55
but one of whom speaks Flemish and one of whom speaks French;
一方はフレミッシュ語
他方はフランス語
09:58
or two families that live in a rural district in Nigeria,
あるいはナイジェリアの
農村部の2世帯で
10:01
one of whom speaks Hausa and one of whom speaks Igbo.
一方はハウサ語
他方はイボ語という具合です
10:04
Now even after all of this granular level of control,
このように細かく条件を絞り込んで
分析した場合
10:07
do futureless language speakers seem to save more?
未来形のない言語話者の方が
貯蓄が多いか?
10:11
Yes, futureless language speakers, even after this level of control,
その通り 任意の年に
「貯蓄した」と回答する確率は
10:14
are 30 percent more likely to report having saved in any given year.
未来形のない言語を話す人の方が
30%高いのです
10:18
Does this have cumulative effects?
累積効果も見られます
10:22
Yes, by the time they retire, futureless language speakers, holding constant their income,
未来形のない言語を話す人々は
退職までに所得を継続的に貯蓄し
10:24
are going to retire with 25 percent more in savings.
退職時点での貯蓄は
25%多くなっています
10:28
Can we push this data even further?
さらに掘り下げてみましょう
10:31
Yes, because I just told you, we actually collect a lot of health data as economists.
せっかく健康に関するデータが
手元にありますから
10:34
Now how can we think about health behaviors to think about savings?
貯蓄のことを念頭において
健康面でどうしているか
10:39
Well, think about smoking, for example.
たとえば喫煙について見てみましょう
10:43
Smoking is in some deep sense negative savings.
喫煙は ある意味
マイナスの貯蓄です
10:46
If savings is current pain in exchange for future pleasure,
貯蓄は「将来の喜び」と引き換えの
「現在の苦しみ」
10:49
smoking is just the opposite.
喫煙は逆です
10:52
It's current pleasure in exchange for future pain.
「将来の苦しみ」に変わる
「現在の喜び」
10:54
What we should expect then is the opposite effect.
それなら
効果も逆になりそうですよね
10:57
And that's exactly what we find.
実際その通りでした
11:00
Futureless language speakers are 20 to 24 percent less likely
未来形のない言語を話す人は
そうでない人と比べ
11:01
to be smoking at any given point in time compared to identical families,
どの時期においても約20~24%
喫煙率が低く
11:05
and they're going to be 13 to 17 percent less likely
退職までに肥満になる確率も
11:08
to be obese by the time they retire,
13~17%低く
11:11
and they're going to report being 21 percent more likely
最近のセックスでコンドームを
使った割合は21%高いという結果でした
11:14
to have used a condom in their last sexual encounter.
最近のセックスでコンドームを
使った割合は21%高いという結果でした
11:16
I could go on and on with the list of differences that you can find.
こうした数値的な差は
枚挙に暇がありません
11:18
It's almost impossible not to find a savings behavior
強い統計的効果なくして
貯蓄行動なしと言っても
11:22
for which this strong effect isn't present.
過言ではないでしょう
11:26
My linguistics and economics colleagues at Yale and I are just starting to do this work
言語学者で経済学者でもある
イェール大学の仲間と共に
11:28
and really explore and understand the ways that these subtle nudges
言語を使うたび 将来の捉え方に
知らず知らずのうちに影響を及ぼす ―
11:33
cause us to think more or less about the future every single time we speak.
その仕組みを解明すべく
本格的に研究を始めました
11:38
Ultimately, the goal,
最終的な目標としては
11:44
once we understand how these subtle effects can change our decision making,
小さな効果の積み重ねが
意思決定を変える仕組みを解明し
11:46
we want to be able to provide people tools
皆さんがより意識的に貯蓄に励み
11:50
so that they can consciously make themselves better savers
将来に向け
有効な投資ができるよう
11:53
and more conscious investors in their own future.
役に立つツールを
提供したいと考えています
11:56
Thank you very much.
ありがとうございました
11:59
(Applause)
(拍手)
12:01
Translated by Tomomi Anzai
Reviewed by Emi Kamiya

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About the Speaker:

Keith Chen - Behavioral economist
Keith Chen's research suggests that the language you speak may impact the way you think about your future.

Why you should listen

Does the future look like a different world to you, or more like an extension of the present? In an intriguing piece of research, Keith Chen suggests that your attitude about the future has a strong relationship to the language you speak. In a nutshell, some languages refer to the future using verb helpers like "will" and "shall," while others don't have specific verbs to refer to future actions. Chen correlated these two different language types with remarkably different rates of saving for the future (guess who saves more?). He calls this connection the "futurity" of languages. The paper is in the process of being published by the American Economic Review, and it's already generated discussion. Chen says: "While the data I analyze don’t allow me to completely understand what role language plays in these relationships, they suggest that there is something really remarkable to be explained about the interaction of language and economic decision-making. These correlations are so strong and survive such an aggressive set of controls, that the chances they arise by random lies somewhere between one in 10,000 and one in 10^32."

Chen excels in asking unusual questions to yield original results. Another work (with Yale colleague and TEDGlobal 2009 speaker Laurie Santos) examined how monkeys view economic risk--with surprisingly humanlike irrationality. While a working paper asks a surprising, if rhetorical, question: Does it make economic sense for a woman to become a physician?

Chen is currently Uber's Head of Economic Research and is an associate professor of economics at UCLA .

Read more about Chen's explorations »

More profile about the speaker
Keith Chen | Speaker | TED.com