The Meat data frame has 30 rows and 4 columns.
This data frame contains the following columns:
an ordered factor specifying the storage treatment - 1 (0 days), 2 (1 day), 3 (2 days), 4 (4 days), 5 (9 days), and 6 (18 days)
a numeric vector giving the tenderness score of beef roast.
an ordered factor identifying the muscle from which the
roast was extracted with levels
II < V < I < III < IV
an ordered factor giving the unique identifier for each pair
of beef roasts with levels II-1 < … < IV-1
Cochran and Cox (section 11.51, 1957) describe data from an experiment conducted at Iowa State College (Paul, 1943) to compare the effects of length of cold storage on the tenderness of beef roasts. Six storage periods ranging from 0 to 18 days were used. Thirty roasts were scored by four judges on a scale from 0 to 10, with the score increasing with tenderness. The response was the sum of all four scores. Left and right roasts from the same animal were grouped into pairs, which were further grouped into five blocks, according to the muscle from which they were extracted. Different storage periods were applied to each roast within a pair according to a balanced incomplete block design.