R: Piedmont wines data

wines {sn} | R Documentation

## Piedmont wines data

### Description

Data refer to chemical properties of 178 specimens of three types of wine produced in the Piedmont region of Italy.

### Usage

    data(wines)

### Format

A data frame with 178 observations on the following 28 variables.

`wine` | wine name (categorical, levels: `Barbera`, `Barolo`, `Grignolino`)
`alcohol` | alcohol percentage (numeric)
`sugar` | sugar-free extract (numeric)
`acidity` | fixed acidity (numeric)
`tartaric` | tartaric acid (numeric)
`malic` | malic acid (numeric)
`uronic` | uronic acids (numeric)
`pH` | pH (numeric)
`ash` | ash (numeric)
`alcal_ash` | alcalinity of ash (numeric)
`potassium` | potassium (numeric)
`calcium` | calcium (numeric)
`magnesium` | magnesium (numeric)
`phosphate` | phosphate (numeric)
`cloride` | chloride (numeric)
`phenols` | total phenols (numeric)
`flavanoids` | flavanoids (numeric)
`nonflavanoids` | nonflavanoid phenols (numeric)
`proanthocyanins` | proanthocyanins (numeric)
`colour` | colour intensity (numeric)
`hue` | hue (numeric)
`OD_dw` | OD₂₈₀/OD₃₁₅ of diluted wines (numeric)
`OD_fl` | OD₂₈₀/OD₃₁₅ of flavanoids (numeric)
`glycerol` | glycerol (numeric)
`butanediol` | 2,3-butanediol (numeric)
`nitrogen` | total nitrogen (numeric)
`proline` | proline (numeric)
`methanol` | methanol (numeric)

### Details

The data represent 27 chemical measurements on each of 178 wine specimens belonging to three types of wine produced in the Piedmont region of Italy. The data have been presented and examined by Forina et al. (1986) and were freely accessible from the PARVUS web-site until it was active. These data or, more often, a subset of them are now available from various places, including some R packages. The present dataset includes all variables available on the PARVUS repository, which are the variables listed by Forina et al. (1986) with the exception of ‘Sulphate’. Moreover, it reveals the undocumented fact that the original dataset appears to include also the vintage year; see the final portion of the ‘Examples’ below.

### Source

Forina, M., Lanteri, S. Armanino, C., Casolino, C., Casale, M. and Oliveri, P. V-PARVUS 2008: an extendible package of programs for esplorative data analysis, classification and regression analysis. Dip. Chimica e Tecnologie Farmaceutiche ed Alimentari, Università di Genova, Italia. Web-site (not accessible as of 2014): http://www.parvus.unige.it

### References

Forina M., Armanino C., Castino M. and Ubigli M. (1986). Multivariate data analysis as a discriminating method of the origin of wines. Vitis 25, 189–201.

### Examples

    data(wines)
    pairs(wines[,c(2,3,16:18)], col=as.numeric(wines$wine))
    #
    code <- substr(rownames(wines), 1, 3)
    table(wines$wine, code)
    #
    year <- as.numeric(substr(rownames(wines), 6, 7))
    table(wines$wine, year)
    # coincides with Table 1(a) of Forina et al. (1986)

[Package sn version 1.5-0 Index]