From the Exploring Data website - http://curriculum.qed.qld.gov.au/kla/eda/
© Education Queensland, 1997

Pecking Order in Chickens

'Pecking order' refers to the relative ranking that often occurs between animals of the same species when they live in close proximity. A researcher on animal behavior wants to study the relationship between pecking order and weight. He places four chickens in each of seven pens and observes the pecking order that emerges in each pen.

The dataset contains the weights (in grams) of the chickens, arranged by pecking order. That is, the first row gives the weight of the dominant chicken in each pen, the second row gives the weight of the second most dominent chicken in each pen, and so on.

As the researcher’s assistant, you have been asked to analyse this data (and possibly generate some graphical displays) and write a report on the relationship, if any, between pecking order and weight.

Justify all conclusions you make.

Source: Data collected by D. L. Cunningham, Cornell University

Weight (g)

Pecking order

Pen 1

Pen 2

Pen 3

Pen 4

Pen 5

Pen 6

Pen 7

1

1880

1300

1600

1380

1800

1000

1680

2

1920

1700

1830

1520

1780

1740

1460

3

1600

1500

1520

1520

1360

1520

1760

4

1830

1880

1820

1380

2000

2000

1800