the first 200 births on the Farm.The C-section rate on the Farm is very low, under 2% for about 3000 births, while the average in the U.S. for low-risk women is 20%. Can you explain?It’s very rare to see an undisturbed birth in a modern U.S. teaching hospital. But when you see a woman who isn’t frightened, who’s giving birth without interference, you stand back in awe and realize how ...
huge mass, the analysis showed, would block the sun on the Korean Peninsula for about two months, resulting in the average temperature dropping by two degrees Celsius. South Korea’s weather agency has pushed to forge a partnership with its counterparts in Japan and China for more accurate weather forecasting including a natural disaster control system.Small-scale eruptions at Mt. Baekdu were ...
대푯값은 자료의 특성을 나타내는 값으로 중앙값, 최빈수, 평균 등이 이에 속한다. average는 mean보다 더 넓은 의미다. 숫자로 가득한 세상을 한결 쉽게 표현해 주는 친절한 그래프의 뿌리를 찾아 여행하면 영어는 물론 통계용어까지 알 수 있다. 수학의 뿌리를 찾아 떠나는 여행은 앞으로도 계속되니 ...
user-written online encyclopedia has expanded exponentially. Up until about two years ago, Wikipedians were adding, on average, some 2,200 new articles to its website every day. The number of registered articles hit the 2 million entries in September 2007 and then the 3 million in August 2009. But early in 2007, something strange happened. Wikipedia’s growth line flattened. People suddenly ...
해도 가장 애용되는 예측기법은 박스와 젠킨스가 만든 ARIMA(Auto Regressive Integrated Moving Average)모형이었다. 박스-젠킨스 모형 (ARIMA)은 데이터가 시간의 흐름에 따라 '확률적'(stochastic)으로 변동한다고 전제한다. 그리고 과거의 누적된 데이터로부터 미래를 예측할 수 있는 동력학(dynamics)을 도출 해 냈다. ...
CD-ROM 디스크내의 자료를 찾아 화면에 출력하기까지 소요되는 시간인 평균 엑세스 시간(average access time)이다.현재 나와 있는 CD-ROM 드라이브들의 전송률은 1초당 1백50KB와 3백KB 2가지 타입이 있다. 초당 1백50KB를 읽어들이는 경우 1배속(single speed), 3백KB를 읽어들이는 경우를 2배속(double speed)이라 하는데, ...
Clouds. These are stars that pulsate. She noted in 1904 that the longer the period of light variation, the greater the average brightness of the star. In 1912, Leavitt had worked out a method for determining the relative distances of various Cepheids.The Cepheids offered the first method of determining really vast distances and man's knowledge of the universe was greatly enlarged as a ...
width of 1.66 seconds of arc?The answer comes out 169,000 light-years, which can now be taken as the distance, on the average, of all the billions of stars in the Large Magellanic Cloud. This is rather gratifying, for it comes out fairly close to the crude approximations of the distance made in earlier times.Nor is the distance of the Large Magellanic Cloud important just for it's own sake. ...
사용할 것인가 하는 것도 연구 대상이 될 수가 있다. 공격득점평균(OERA, Offensive Earned Run Average, 이를 계산하기 위해서는 통계학적으로 매우 여러단계를 거치기 때문에 계산과정은 생략)이란 통계를 도입해서 미국 야구 역사상 누가 가장 좋은 타자인가를 가려보니, 타율이 0.367로 제일 높은 타이 콥(Ty ...
the problem very seriously. After all, there are estimates that a “citybusting” strike might happen, on the average, once in 50,000 years, and it's been that long since the Arizona crater. We might be due, so to speak.Of course, if we smash up a small asteroid, the rubble will continue in its orbit, perhaps, but then if that does strike the Earth, each individual bit can't do much damage. ...
동아사이언스
디라이브러리
DS스토어
팝콘플래닛
