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A central composite design with 4 factors in 2 blocks. These data comprise a coded.data object.

Usage

heli

Format

A data frame with 30 observations on the following 7 variables. Each observation reflects the results of 10 replicated flights under the same experimental conditions.

block

a factor with levels 1 2. Block 1 consists of 18 observations (a full factorial plus two center points). Block 2 consists of 12 observations -- 8 axis points and 4 center points.

x1

a numeric vector. Coded wing area, x1 ~ (A - 12.4)/.6

x2

a numeric vector. Coded length ratio, x2 ~ (R - 2.52)/.26

x3

a numeric vector. Coded body width, x3 ~ (W - 1.25)/.25

x4

a numeric vector. Coded body length, x4 ~ (L - 2)/.5

ave

a numeric vector. Average flight time, in csec.

logSD

a numeric vector. 100*log(SD of times).

Source

Table 12.5 of Box, GEP, Hunter, JS, and Hunter, WG (2005) Statistics for Experimenters (2nd ed.), Wiley.