glm() in R (PR#1457)

On 13 Apr 2002, Peter Dalgaard BSA wrote:

popescul@unagi.cis.upenn.edu writes:

 Hello,

 I was using R for logistic regression modeling (glm() with binomial
family) and have noticed that it' can't handle more than 100 predictors
(reports syntax error)
Is it a bug, or a language restiction ?

 I would be very grateful if you let me know possible ways around the
problem, as I need R for problems with many attributes.

 Thank you,

 Alex.

If you get a syntax error, then I wouldn't expect that glm() itself is
causing it. More likely, you are exceeding the line length limit in
the parser. Try splitting your command over several lines, or use
simplified formulas like  glm(V1~.,data=d,family=binomial).

To be specific, I defined
y<-rbinom(800,1,.5)
x<-as.data.frame(matrix(rnorm(800*300),ncol=300))

and the following all work
# using . to specify variables implicitly
glm(y~.,data=x,family=binomial())

# constructing a formula object
ff<-formula(paste("y",paste(names(x),collapse="+"),sep="~")
glm(ff,data=x,family=binomial())

# constructing the whole call as a text string and evaluating it
expr<-paste("glm(y~",paste(names(x),collapse="+"),",data=x,family=binomial())")
eval(parse(text=expr)[[1]])

#pasting the whole thing in multiple lines
 glm(y ~ V1 + V2 + V3 + V4 + V5 + V6 + V7 + V8 + V9 + V10 + V11 +
    V12 + V13 + V14 + V15 + V16 + V17 + V18 + V19 + V20 + V21 +
    V22 + V23 + V24 + V25 + V26 + V27 + V28 + V29 + V30 + V31 +
     V32 + V33 + V34 + V35 + V36 + V37 + V38 + V39 + V40 + V41 +
     V42 + V43 + V44 + V45 + V46 + V47 + V48 + V49 + V50 + V51 +
    V52 + V53 + V54 + V55 + V56 + V57 + V58 + V59 + V60 + V61 +
    V62 + V63 + V64 + V65 + V66 + V67 + V68 + V69 + V70 + V71 +
    V72 + V73 + V74 + V75 + V76 + V77 + V78 + V79 + V80 + V81 +
    V82 + V83 + V84 + V85 + V86 + V87 + V88 + V89 + V90 + V91 +
    V92 + V93 + V94 + V95 + V96 + V97 + V98 + V99 + V100 + V101 +
    V102 + V103 + V104 + V105 + V106 + V107 + V108 + V109 + V110 +
   V111 + V112 + V113 + V114 + V115 + V116 + V117 + V118 + V119 +
   V120 + V121 + V122 + V123 + V124 + V125 + V126 + V127 + V128 +
   V129 + V130 + V131 + V132 + V133 + V134 + V135 + V136 + V137 +
   V138 + V139 + V140 + V141 + V142 + V143 + V144 + V145 + V146 +
   V147 + V148 + V149 + V150 + V151 + V152 + V153 + V154 + V155 +
    V156 + V157 + V158 + V159 + V160 + V161 + V162 + V163 + V164 +
   V165 + V166 + V167 + V168 + V169 + V170 + V171 + V172 + V173 +
    V174 + V175 + V176 + V177 + V178 + V179 + V180 + V181 + V182 +
    V183 + V184 + V185 + V186 + V187 + V188 + V189 + V190 + V191 +
    V192 + V193 + V194 + V195 + V196 + V197 + V198 + V199 + V200 +
    V201 + V202 + V203 + V204 + V205 + V206 + V207 + V208 + V209 +
    V210 + V211 + V212 + V213 + V214 + V215 + V216 + V217 + V218 +
  V219 + V220 + V221 + V222 + V223 + V224 + V225 + V226 + V227 +
     V228 + V229 + V230 + V231 + V232 + V233 + V234 + V235 + V236 +
     V237 + V238 + V239 + V240 + V241 + V242 + V243 + V244 + V245 +
     V246 + V247 + V248 + V249 + V250 + V251 + V252 + V253 + V254 +
     V255 + V256 + V257 + V258 + V259 + V260 + V261 + V262 + V263 +
     V264 + V265 + V266 + V267 + V268 + V269 + V270 + V271 + V272 +
     V273 + V274 + V275 + V276 + V277 + V278 + V279 + V280 + V281 +
     V282 + V283 + V284 + V285 + V286 + V287 + V288 + V289 + V290 +
  V291 + V292 + V293 + V294 + V295 + V296 + V297 + V298 + V299 +
  V300, data = x, family = binomial())

but pasting it as a single line gives a syntax  error.


	-thomas