以下是在 2012 年奥运会男子跳远预选赛中成功完成合法跳跃的 40 名运动员的结果,以核密度图显示,下方是地毯图。
落后主要竞争对手一米似乎比领先一米要容易得多,这可以解释负偏度。
我怀疑在顶端的一些聚集是由于运动员的目标是资格(需要前 12 名或 8.10 米或以上的成绩),而不是达到可能的最长距离。前两名成绩为 8.11 米,略高于自动排位线,这一事实强烈暗示,决赛中获得奖牌的跳跃在 8.31、8.16 和 8.12 米处更长且分布更广。决赛的结果有轻微的、不显着的负偏差。
为了比较,1988 年首尔奥运会七项全能的结果可在heptathlon
R 包中的数据集中获得HSAUR
。在那场比赛中没有资格赛,但每项赛事都为最终排名贡献了积分;女选手在跳高成绩中表现出明显的负偏度,在跳远中表现出一定程度的负偏度。有趣的是,这在投掷项目(射击和标枪)中没有被复制,尽管它们也是数字越大对应于更好结果的项目。最后的分数也有些负面。
数据和代码
require(moments)
require(ggplot2)
sourceAddress <- "http://www.olympic.org/olympic-results/london-2012/athletics/long-jump-m"
longjump.df <- read.csv(header=TRUE, sep=",", text="
rank,name,country,distance
1,Mauro Vinicius DA SILVA,BRA,8.11
2,Marquise GOODWIN,USA,8.11
3,Aleksandr MENKOV,RUS,8.09
4,Greg RUTHERFORD,GBR,8.08
5,Christopher TOMLINSON,GBR,8.06
6,Michel TORNEUS,SWE,8.03
7,Godfrey Khotso MOKOENA,RSA,8.02
8,Will CLAYE,USA,7.99
9,Mitchell WATT,AUS,7.99,
10,Tyrone SMITH,BER,7.97,
11,Henry FRAYNE,AUS,7.95,
12,Sebastian BAYER,GER,7.92,
13,Christian REIF,GER,7.92,
14,Eusebio CACERES,ESP,7.92,
15,Aleksandr PETROV,RUS,7.89,
16,Sergey MORGUNOV,RUS,7.87,
17,Mohammad ARZANDEH,IRI,7.84,
18,Ignisious GAISAH,GHA,7.79,
19,Damar FORBES,JAM,7.79,
20,Jinzhe LI,CHN,7.77,
21,Raymond HIGGS,BAH,7.76,
22,Alyn CAMARA,GER,7.72,
23,Salim SDIRI,FRA,7.71,
24,Ndiss Kaba BADJI,SEN,7.66,
25,Arsen SARGSYAN,ARM,7.62,
26,Povilas MYKOLAITIS,LTU,7.61,
27,Stanley GBAGBEKE,NGR,7.59,
28,Marcos CHUVA,POR,7.55,
29,Louis TSATOUMAS,GRE,7.53,
30,Stepan WAGNER,CZE,7.50,
31,Viktor KUZNYETSOV,UKR,7.50,
32,Luis RIVERA,MEX,7.42,
33,Ching-Hsuan LIN,TPE,7.38,
33,Supanara SUKHASVASTI N A,THA,7.38,
35,Boleslav SKHIRTLADZE,GEO,7.26,
36,Xiaoyi ZHANG,CHN,7.25,
37,Mohamed Fathalla DIFALLAH,EGY,7.08,
38,Roman NOVOTNY,CZE,6.96,
39,George KITCHENS,USA,6.84,
40,Vardan PAHLEVANYAN,ARM,6.55,
NA,Luis MELIZ,ESP,NA,
NA,Irving SALADINO,PAN,NA")
roundedSkew <- signif(skewness(longjump.df$distance, na.rm=TRUE), 3)
ggplot(longjump.df, aes(x=distance)) +
xlab("Distance in metres") +
ggtitle("London 2012 Men's Long Jump qualifying round results") +
geom_rug(size=0.8) +
geom_density(fill="steelblue") +
annotate("text", x=7.375, y=0.0625, colour="white", label=paste("Source:", sourceAddress), size=3) +
annotate("rect", xmin = 6.25, xmax = 7.25, ymin = 0.5, ymax = 1.125, fill="white") +
annotate("text", x=6.75, y=1, colour="black", label="Best jump in up to 3 attempts") +
annotate("text", x=6.75, y=.875, colour="black", label="42 athletes competed") +
annotate("text", x=6.75, y=.75, colour="black", label="2 athletes had no legal jump") +
annotate("text", x=6.75, y=.625, colour="black", label=paste("Skewness = ", roundedSkew))
# Results of the top twelve who qualified for the Final were closer to symmetric
skewness(longjump.df$distance[1:12])
# -0.1248782
# Results in the Final (some had 3 jumps, others 6) were only slightly negatively skewed
skewness(c(8.31, 8.16, 8.12, 8.11, 8.10, 8.07, 8.01, 7.93, 7.85, 7.80, 7.78, 7.70))
# -0.08578357
# Compare to Seoul 1988 Heptathlon
require(HSAUR)
skewness(heptathlon)