# helicopter: Helicopter Data In nlreg: Higher Order Inference for Nonlinear Heteroscedastic Models

## Description

The `helicopter` data frame has 9 rows and 6 columns.

Experimental design for studying the influences of the factors wing length and wing width on a paper helicopter's flight time. The goal is to find the factor setting that maximizes flight time when the paper helicopter is dropped from a fixed height of 15.5 feet

## Usage

 `1` ```data(helicopter) ```

## Format

A data frame with 9 observations on the following 6 variables:

`L`

wing length in inches;

`W`

wing width in inches;

`B`

base length (always set to 3in);

`H`

base height (always set to 2in);

`Order`

run order;

`Time`

flight time in seconds.

## Source

The data were obtained from

Annis, D. H. (2006) Rethinking the paper helicopter: Combining statistical and engineering knowledge. The American Statistician, 59, 320–326.

## References

Box, G. E. P. (1992) Teaching engineers experimental design with a paper helicopter. Quality Engineering, 4, 453–459.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13``` ```data(helicopter) ## ## fit model (5) of Annis (2005) ## ----------------------------- heli <- helicopter ## heli\$LW <- heli\$L * heli\$W heli\$S <- heli\$B * heli\$H + ( 2 * heli\$L + 1 ) * heli\$W heli\$logTime <- log( heli\$Time ) heli\$Y <- heli\$logTime + log( heli\$S ) / 2 # heli.nlreg <- nlreg( Y ~ b0 + b1 * log( b2^2 / LW + LW ), data = heli, start = c( b0 = 6, b1 = -1, b2 = 20 ) ) ```

### Example output

```Loading required package: statmod

Package "nlreg" 1.2-2 (2014-03-31)
Copyright (C) 2000-2014 R. Bellio & A. R. Brazzale

This is free software, and you are welcome to redistribute
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