If you group them by month of birth, something interesting happens.

如果按照出生月份把他們分組，會發現有趣的現象。

Do you see it? I'll give you a hint.

你看到了嗎？讓我給你一個提示

There are significantly more players born in the first 6 months than in the last 6 months of the year.

在出生月份方面，1 月至 6 月出生的球員人數明顯多於 7 月至 12 月出生的球員。

This is caused by a phenomenon called the relative age effect.

這是由一種被稱為「相對年齡效應」的現象所引起的。

I'll explain what that means.

我來解釋它的意思。

Let's say it's December 31st of 2022.

比方說，現在是 2022 年 12 月 31 日。

Two friends meet for a birthday party.

兩個朋友相約參加一個生日聚會。

Red was born on january 1st 2004.

小紅於 2004 年 1 月 1 日出生。

Blue, the birthday boy, was born on December 31st and just turned 18.

小藍，也就是壽星，出生於 12 月 31 日，剛滿 18 歲。

Right now they are both 18 and you wouldn't notice the differences between them.

現在他們都是18歲，你不會注意到他們之間的差異。

Afterall, Red is only 6% older than Blue.

畢竟，紅色只比藍色大 6% 的年紀。

However, if we travel back in time it's a different story.

然而，如果我們穿越時空回到過去，情況就不同了。

Let's go back to their first day of primary school.

讓我們回到他們上小學的第一天。

It's now September 1st of 2010.

現在是 2010 年 9 月 1 日。

Even though the difference between their ages is still 11 months and 30 days, the relative age difference increased.

儘管他們的年齡仍然相差 11 個月又 30 天，但相對年齡差異增加了。

Red is now 18% older than Blue.

紅色現在的年紀比藍色大 18% 。

At this age, the 11 additional months he had to grow make a difference and you can see it.

在這個年齡段，他多出的 11 個月的成長時間產生了差異，且顯而易見。

He's taller, stronger and mentally more developed, which gives him an advantage in sports and school.

他更高大，更強壯，心智更成熟，這讓他在體育和學業方面有優勢。

This is known as relative age effect: people born earlier in the school or sports year tend to perform to a higher level than those born at the end of the year.

這被稱為相對年齡效應，即在學校或體育年份出生較早的人往往比年底出生的人表現出更高的水準。

But if we travel back to 2022 these differences should disappear. right?

但如果我們穿越到 2022 年，這些差異應該會消失吧？

Well, not really.

並不ㄧ定。

Research shows us is that even when we become adults, people who were older than their peers during childhood still have an advantage in sports, education and even in positions of leadership.

研究表明，即使當我們成年後，童年時比同齡人更年長的人在運動、教育甚至領導職位上仍然具有優勢。

The small advantages at an early age can build up into bigger advantages in adulthood.

幼年時的小優勢可以積累成成年後的大優勢。

This is known as the Matthew effect, aka "The rich get richer, the poor get poorer".

這被稱為「馬太效應」，也被稱為「富者愈富，貧者愈窮」。

What is a small advantage at the start can develop into a bigger advantage later on.

在一開始是小小的優勢可以發展成為更大的優勢。

The point of this video is to talk about how the relative age effect can impact success in education, sports, career and what we can do about it.

這個影片的重點是討論相對年齡效應如何影響教育、體育、職業的成就，以及我們可以採取什麼措施來應對這種影響。

Let's start with Sports.

讓我們從體育開始說起。

In most sports, children are grouped based on their calendar year of birth.

在大多數體育中，兒童是根據他們的出生年份進行分組的。

On average, children born earlier in the year are taller, stronger and faster.

平均而言，年初出生的孩子身高更高，體格更強壯，速度更快。

Therefone, an older child will have a higher chance of being selected by the coach to play.

所以，年齡較大的孩子被教練選中參加比賽的機會會更大。

Being selected to play, means the child gets more experience, becomes better and ends up with higher chances of becoming a professional athlete later on.

被選中參加比賽代表孩子可以獲得更多的經驗，變得更加優秀，最終有更高的機會成為職業運動員。

It's the Matthew effect.

這就是馬太效應。

The older player is picked because he is better, and then ends up becoming better with time because he was picked, apparently validating the early decision of the coach.

年齡較大的球員被選中是因為他更優秀，然後由於被選中，隨著時間的推移表現得越來越好，這似乎驗證了教練初期的決定。

It's a self-fulfilling prophecy.

這是一個自我實現的預言。

There's plenty of research about the relative age effect in sports.

關於相對年齡效應在體育中的影響有大量的研究。

There's studies in football, baseball, ice hockey, tennis, you name it.

在足球、棒球、冰上曲棍球、網球等體育中都有相關的研究。

I decided to share the findings of this study in Sweden.

我決定分享這項在瑞典進行的研究發現。

I chose it because it's quite recent and, honestly, because it's the first result on Google.

我之所以選擇這項研究是因為它比較近期，而且老實說，它是谷歌上出現的第一個搜索結果。

Their conclusions: the birthdate distributions were consistently skewed for every individual sport they investigated.

他們的結論是：對於他們調查的每個體育項目，出生日期的分布都存在顯著的偏斜情況。

They looked at different sports and analyzed the birthdays of every athlete.

他們研究了不同的運動，並分析了每個運動員的生日。

They grouped them in blocks of 4 months (also known as tertiles) and they compared the actual number of athletes per tertile against the numbers that you would expect from looking at the births of the population in Sweden.

他們將出生日期分為每四個月一組（也稱為三分位），並比較了每個三分位的實際運動員人數與從瑞典人口出生率估算出的期望數字。

The y-axis shows the ratio between these two numbers.

y 軸顯示了這兩個數字之間的比率。

In other words, if the ratio is higher than 1, that means there is an abnormally high number of athletes born in those months.

換句話說，如果比率高於 1，這意味著在這些月份出生的運動員人數異常高。

They looked at 14 to 17 year old athletes in Athletics and they got these results.

他們研究了 14 至 17 歲田徑運動員，並得出以下結果：

Take a second to see what this means.

花一點時間看看這代表什麼。

There's 27% more athletes born in the beginning of the year than what would be normal for the Swedish population, and 28% fewer at the end of the year.

在這個年齡段的田徑運動員中，在年初出生的運動員比在瑞典人口中的期望值多出 27%，而在年末出生的運動員則比期望值少了 28%。

These are big gaps.

這是很大的差距。

If the results are accurate this means that teenagers born in the first tertile are 74% more likely to become athletes than those born in the last tertile.

如果這些結果是準確的，這表示出生在第一個三分位的青少年比出生在最後一個三分位的青少年更有可能成為運動員，其機率高出 74%

The authors frame the results in way that might give a better picture of what this means.

這些作者的報告用一種更好的方式來呈現這些結果。

In theory, these gaps represent the "Missed Stars".

理論上，這些差距代表著「被錯過的明星」。

Teenagers that had the potential but never made it as athletes because of the month they were born in,

這些青少年因為出生的月份而沒有成為運動員，即使他們具有潛力，

whereas this gap represents the athletes that are quote "Not Talented" - teenagers that wouldn't have made it as athletes if the rules were even.

而這種差距則代表著「沒有天賦」的運動員——如果運動員的選拔規則公平無私，這些青少年不會成為運動員。

The gap is not as big for older age groups, but it's still there.

年齡較大的群體之間的差距不會像年輕群體那麼大，但仍然存在。

They also found similar results in cross-country skiing and alpine skiing

他們在越野滑雪和高山滑雪中也發現了類似的結果。

The authors even mention that the relative age effect can have a negative impact on public health because it can reduce the lifetime levels of physical activity.

作者甚至提到相對年齡效應可能對公眾健康產生負面影響，因為它可能會降低ㄧ生中的體育活動水準。

They even found a reverse relative age effect in E-sports for some age groups.

他們甚至在某些年齡段中的電子競技中發現了相反的相對年齡效應。

They suggest the hypothesis that relatively younger children are more likely to dropout from physical sports and focus more on other hobbies, like playing video games.

他們提出的假設是，相對年齡較小的孩子更有可能退出體育運動，轉而專注於其他愛好，如玩電子遊戲。

One import note: In most investigated sports, the birthdate distribution was not correlated to the performance of the adults.

重要的一點是，在大多數研究的運動中，出生日期分布與成年人的表現沒有相關性。

In other words, being born early means you get a higher chance of being selected to play when young.

換句話說，出生日期較早意味著你在年幼時被選中參加比賽的機會更高。

But once you're older and you're part of those selected, it doesn't really matter.

但是當你年紀越大，被挑選入隊之後，就不太重要了。

Some studies even mention the underdog hypothesis - since younger children are less physically mature, they must possess or develop superior skills to be competitive.

一些研究甚至提到了「弱者優勢假說」，由於年紀較小的孩子生理上不如年長的成熟，所以必須擁有或發展出卓越的技能才能相互競爭。

The relative age effect is also present in education.

相對年齡效應也存在於教育領域。

Each country has their own criteria to determine to which school year students belong.

每個國家都有自己的標準來判斷學生屬於哪個學年。

In some countries, like Portugal, where I'm from, the cut-off date is December 31st.

在一些國家，例如我的祖國葡萄牙，入學年齡的切割日期是 12 月 31 日。

This means January kids are the oldest in class.

這表示一月份出生的孩子在班上是最年長的。

In the Southern Hemisphere, February and March are common cut-off months, whereas August and September are more common in the Northern Hemisphere.

在南半球，普遍的切割月份是二月和三月，而在北半球，八月和九月更為普遍。

No matter what cut-off date we choose, we're going to end up with a group of students with older and younger children.

無論選擇什麼切割日期，都會出現一群較年長和較年幼的學生。

Older children are cognitively more developed.

年長的兒童在認知上更加發達。

As a result, they score higher marks on average, and, by the time they end school, they can be more likely to attend higher education in academic schools over vocational schools.

正因如此，他們平均成績較高，並且在結束學校時，可能更有可能進入學術學校而非職業學校。

Once again, the Matthew effect.

再説一次，這又是馬太效應。

The skills learned by the older students early in school can build up and increase their advantage when applying to university later on.

年紀較長的學生在學校早期學習到的技能可以累積起來，並增加他們在之後申請大學時的優勢。

There is plenty of research pointing to a relative age effect on education.

有大量的研究指出相對年齡效應對教育有影響。

For example, this study looked at the performance of Dutch teenagers in school for each month of birth.

例如，這項研究調查了荷蘭十幾歲學生在學校表現的出生月份。

In the Netherlands, October kids are the oldest of the class.

在荷蘭，十月生的孩子是班上年齡最大的。

The authors analyzed the percentage of students that had to repeat a grade and, as expected, the younger students struggled the most.

作者分析了需要重讀的年級的學生百分比，而像預期的一樣，年齡較小的學生遇到的困難最多。

They also checked the percentage of students that skipped a grade and, once again, the older students performed the best.

他們還檢查了跳級學生的比例，結果再次顯示年齡較大的學生表現最好。

So, we came to the conclusion that the relative age effect has an impact in sports and education.

因此，我們得出的結論是。相對年齡效應對體育和教育皆有影響。

We've also seen how small early advantages can build up to bigger advantages later on

我們也看到了早期的小優勢如何累積成為後來更大的優勢。

Therefore, it's not a surprise that this can also affect your career.

因此，這會影響你的職涯也不意外。

There are studies in the US Senate and House of Representatives, in Finish Politics, and even in the corporate CEOs of S&P 500 Companies.

有研究分析了美國參議院和眾議院、芬蘭政治，甚至是標準普爾 500 指數的企業 CEO。

These studies all have similar conclusions: professionals who were born in late months of the school calendar are underrepresented in positions of leadership.

這些研究都得出了類似的結論：在領導職位上，出生在學年後幾個月的專業人士佔比較少。

So, what can we do to solve the relative age effect?

那麼，我們能做什麼來解決相對年齡效應呢？

Well, unfortunately if you're watching this video, it's probably a bit too late to do much for yourself.

不幸的是，如果你正在看這個影片，現在要做點什麼有點太晚了。

However, what what we can is to try to reduce this effect on our younger generations.

然而，我們能做的就是努力減少對我們年輕一代的影響。

Research on this topic often mentions the same point: We should separate children based on abilities, not on their age.

關於這個話題的研究經常提到同一個觀點：我們應該根據能力而不是年齡來區分孩子。

In sports, children should be selected based on skill, not on size or strength.

在體育方面，應根據技能而不是體型或力量來選擇兒童。

And In schools, children should be allowed to learn at their own pace.

在學校裡，應該允許孩子們按照自己的節奏學習。

Finally, we should educate coaches and leaders on the consequences of the relative age effect, which is also the point of this video.

最後，我們應該對教練和領導者進行相對年齡效應的後果教育，這也是本部影片的重點。

If you like stories told with Data, consider liking the video and subscribing to the channel.

如果你喜歡 Data 講述的故事，請考慮給這支影片按讚並訂閱我們頻道。

We're getting more people to work on our videos and we're trying to scale up the channel so we can keep improving with our content.

我們正在吸引更多的人來製作我們的影片，我們正在努力擴大頻道規模，以便我們可以不斷改進我們的內容。

If you want to help us with this project, you can support us on Patreon in the link in the description.

如果你想幫助我們完成項目，你可以在說明欄中的連結通過 Patreon 支持我們。

We'll see you for the next video!

我們下支影片見！