Chapter02 {DanielBiostatistics10th} | R Documentation |

## Chapter 2: Descriptive Statistics

### Description

Functions and examples for Chapter 2, *Descriptive Statistics*.

### Usage

```
print_stats(x, na.rm = TRUE)
print_freqs(x, breaks, include.lowest = TRUE, right = TRUE)
```

### Arguments

`x` |
numeric vector, the observations. In function print_freqs, this argument can also be a factor |

`na.rm` |
logical scalar, whether to remove the missing observations (default |

`breaks` |
numeric vector, see cut.default |

`include.lowest` |
logical scalar, default |

`right` |
logical scalar, see cut.default |

### Details

Function print_freqs prints the (relative) frequencies and cumulative (relative) frequencies, from a numeric input vector, specified interval breaks as well as open/close status of the ends of the intervals.

Function print_stats prints the simple statistics of the input observations, such as sample size, mean, median, (smallest) mode, variance, standard deviation, coefficient of variation (if all observations are non-negative), quartiles, inter-quartile range (IQR), range, skewness and kurtosis. A histogram is also printed.

### Value

Function print_freqs returns a freqs object, for which a show method is defined.

Function print_stats does not have a returned value.

### See Also

cut.default table cumsum mean.default median.default Mode var sd quantile skewness kurtosis

### Examples

```
library(DanielBiostatistics10th)
# Example 2.2.1; Page 20 (10th ed), Page 19 (11th ed)
head(EXA_C01_S04_01)
class(age <- EXA_C01_S04_01$AGE) # 'integer'
sort(age) # Table 2.2.1
# Example 2.3.1; Page 23 (10th ed); Page 22 (11th ed)
(r231 = print_freqs(age, breaks = seq.int(from=30, to=90, by=10), right = FALSE)) # Table 2.3.2
# The open/close of interval ends is determined by textbook using 30-39, 40-49, etc.
# Example 2.4.1-2.4.6; Page 38-42 (10th ed); Page 30-34 (11th ed)
# Example 2.5.1-2.5.3; Page 44-46 (10th ed); Page 35-41 (11th ed)
print_stats(age) # or some other data input
# Example 2.5.4 (omitted); Page 49 (10th ed), Page 41 (11th ed)
# Example 2.5.5; Page 50 (10th ed)
head(EXA_C02_S05_05)
boxplot(EXA_C02_S05_05$GRF, main = c('Example 2.5.5 (10th ed)'))
print_stats(EXA_C02_S05_05$GRF)
print_freqs(EXA_C02_S05_05$GRF, breaks = seq.int(10, 45, by = 5))
```

*DanielBiostatistics10th*version 0.2.2 Index]