mydata <- read.table("Marathon.csv", header = TRUE, sep = ";", dec = ",")
head(mydata)
## ID Weight Height Pressure Beat Hemoglobin Hematocrit Cholesterol Glucose
## 1 1 72 179.0 105 64 160 50 4.9 4.7
## 2 2 68 178.0 105 60 158 51 4.8 4.9
## 3 3 64 174.0 109 54 155 51 4.5 7.0
## 4 4 63 174.0 112 54 153 58 8.0 7.2
## 5 5 61 173.5 100 53 152 59 4.6 6.7
## 6 6 60 173.0 99 53 158 49 3.9 6.0
## Gender
## 1 1
## 2 0
## 3 0
## 4 0
## 5 0
## 6 0
mean(mydata$Height)
## [1] 176.9571
Average height for people, included in the sample, is 176.96 cm.
sd(mydata$Height)
## [1] 5.85156
Standard deviation, which is meausre of variability, equals 5.85 cm.
If assuming that height is distributed normally in people, then within 176.96 cm +- 5.85 cm 68.3 % of people are expected to be.
mydata$Gender <- factor(mydata$Gender,
levels = c(0, 1),
labels = c("F", "M"))
library(psych)
describeBy(mydata$Glucose, group = mydata$Gender)
##
## Descriptive statistics by group
## group: F
## vars n mean sd median trimmed mad min max range skew kurtosis se
## X1 1 14 5.96 0.93 5.8 5.97 1.33 4.6 7.2 2.6 0.12 -1.62 0.25
## ------------------------------------------------------------
## group: M
## vars n mean sd median trimmed mad min max range skew kurtosis se
## X1 1 21 4.54 0.7 4.6 4.45 0.74 3.8 6 2.2 0.97 -0.13 0.15