[R] Change class factor to numeric

[Prof Brian Ripley]

On Fri, 6 May 2005, Paulo Justiniano Ribeiro Jr wrote:

> as.numeric()

No, please see FAQ 7.10.

> On Fri, 6 May 2005, Smit, R. (Robin) (IenT) wrote:
>
>> I am attempting to develop a multiple regression model using selected
>> model variables that should all be treated as numeric (mostly real)
>> values.
>> However, R considers one specific variable "mass" automatically to be of
>> class "factor", probably because "mass" consists of integer values that
>> are repeated.

Rather, you made it of class factor: R just follows instructions.

>> I now want to force R to treat "mass" as a numeric variable in the
>> regression but am not sure how to do this.
>>
>>> class(mass) <- "numeric"
>>
>> does not help me.
>>
>> Could anyone advise me on this?
>>
>> Kind regards,
>> Robin Smit
>>
>>
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>>
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>
> Paulo Justiniano Ribeiro Jr
> LEG (Laboratório de Estatística e Geoinformação)
> Departamento de Estatística
> Universidade Federal do Paraná
> Caixa Postal 19.081
> CEP 81.531-990
> Curitiba, PR  -  Brasil
> Tel: (+55) 41 361 3573
> Fax: (+55) 41 361 3141
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> http://www.est.ufpr.br/~paulojus
>
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-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595