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Error attaining non linear regression diagnostic plots in R


So i have my code here with a great deal of data points, the 3 variables are all exactly the same length and the regression was highly significant.

Distance<-c(0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,15 ,15 ,15 ,15 ,15 ,15 ,15 ,15 ,15 ,15 ,15 ,15, 15 ,15, 15 ,15 ,15 ,15,15 ,15 ,20, 20 ,20, 20 ,20, 20 ,20, 20 ,20 ,20 ,20 ,20 ,20 ,20, 20 ,20, 20 ,20, 20 ,20, 20)
Height<-c(400   ,300 ,  200,     0  ,-200 , -400  ,-600 , -800 ,-1000 ,-1000 ,-1200, -1220 ,-1300 ,-1400,-1400 ,-1500, -1600, -1700 ,-1700 ,-1800 ,-1900 ,  400 ,  200 ,    0  ,-200,  -400  ,-600 , -800,-1000 ,-1200, -1200 ,-1400 ,-1600 ,-1600 ,-1800 ,-2000 ,-2000 ,-2200 ,-2200 ,-2400 ,-2600 ,-2800,-3000  , 400 ,  200  ,   0  ,-200  ,-300 , -400 , -500  ,-600  ,-700  ,-800  ,-900 ,-1000 ,-1100,-1200 ,-1200 ,-1400, -1600 ,-1800 ,-1800 ,-2000 ,-2200 ,-2400 ,-2400 ,-2600 ,-2800 ,-3000  , 400,200  ,   0,  -200,  -400  ,-600  ,-800, -1000 ,-1200 ,-1400 ,-1600 ,-1600 ,-1800 ,-2000, -2200,-2400 ,-2400, -2600, -2800 ,-3000  ,1000 ,  800  , 600 ,  400  , 200  ,   0  ,-200 , -400 , -600, -800 ,-1000, -1200 ,-1400, -1600 ,-1800, -2000 ,-2200, -2400 ,-2600 ,-2800 ,-3000)
Value<-c(163301.080, 269704.110 ,334570.550, 409536.530, 433021.260 ,418962.060, 349554.460, 253987.570,124461.710, 140750.480  ,52612.790 , 54286.427  ,26150.025  ,14631.210  ,15780.244 ,  8053.618, 4402.581,   2251.137  , 2743.511 ,  1707.508 ,  1246.894 ,176232.060 ,270797.240 ,323096.710,333401.080, 311949.900 ,272821.770 ,189571.850 ,114263.560  ,51939.070  ,62578.665  ,36905.438,  22625.515,  22940.591  ,14576.295  , 9686.653 , 10344.214  , 6912.779  , 7092.919   ,5366.797, 4058.492,   3270.734  , 2528.644  ,89311.555 ,116698.175 ,143588.620 ,139203.190, 145399.445, 145635.715, 134671.110 ,128931.160 ,119734.835 ,108708.815 , 90221.955  ,81692.585 , 64882.275,58215.735,  60443.190  ,44690.690 , 33224.152 , 24140.272 , 24913.280  ,19082.689  ,13920.669, 11074.718,  10015.653   ,8743.850  , 7516.880 ,  6377.743 , 36888.842  ,43088.720  ,47904.490, 51298.710,  51120.887  ,47687.488  ,42238.912 , 38563.007 , 33902.918  ,28565.303  ,23700.862,24818.393,  21620.129 , 17816.061  ,15377.097 , 12992.321  ,12985.911  ,11177.941   ,9536.621,8357.279,  13052.178 , 14325.789  ,15120.314 , 16227.575  ,17226.307  ,18557.270  ,18680.326, 18844.544,  18205.607,  17770.311  ,16605.438 , 16062.309  ,14785.654  ,14324.493  ,13373.627,12135.392,  10632.699,   9155.762  , 8240.951,   6934.240  , 6475.927)
framed=data.frame(Distance,Height,Value)

fit<-nls(Value~a*exp(-(Height+b)^2/(2*c^2))+d*exp(-(Distance)^2/(2*e^2)), data=framed, start = list(a=410000,b=200,c=500,d=205000,e=7.5))
summary(fit)
layout(matrix(c(1,2,3,4),1,1))
plot(fit) 

However when i attempt to get the diagnostics I get this error message

Error in xy.coords(x, y, xlabel, ylabel, log) : 
  'x' is a list, but does not have components 'x' and 'y'

I had a look at some of the other examples of problems solved for this error message, however either they don't seem to be applicable to my situation or my noobishness with R prohibits them from being usable.

Any Suggestions?


Solution

  • Non-linear least squares (nls) objects do not come with a plotting method in R the way that linear models (lm) objects do. You can confirm this by running getS3method("plot", "nls").

    Some of your options are:

    • Build a plot yourself, such as is described here

    • You could use the nlme package's method for plotting nls objects:

      library(nlme)
      plot(fit)
      

    On your data this looks like:

    enter image description here