Dear R users,

I would like to fit a GLM to some plant regeneration data (see bottom
of this e-mail). The dependent variable, an index of regeneration, was
obtained by diviving the number of saplings by the number of adults
plants present in each plot. The result is a highly skewed variable and
thus, specifying, for instance, a
Gaussian distribution does not seem to be appropriate. Data
transformation does not help either. Do you have any suggestion on the
best distribution to choose?


any help would be greatly appreciated!

Best wishes,

Adara

"saplings","adults","regeneration"
0,1,0
0,2,0
450,4399,0.1
2416,25340,0.1
6,72,0.08
0,6,0
0,8,0
61,95,0.64
6,98,0.06
5,59,0.08
55,88,0.63
216,19,11.37
6,1,6
72,178,0.4
26,42,0.62
6,4,1.5
0,2,0
0,1,0
229,533,0.43
0,43,0
5,27,0.19
28,86,0.33
0,102,0
0,2,0
1,5,0.2
0,1,0
2,26,0.08
0,4,0
11,13,0.85
0,59,0
0,73,0
223,100,2.23
0,2,0
6,5,1.2
0,16,0
104,170,0.61
0,1,0
2,69,0.03
4,88,0.05
51,180,0.28
3,1,3
12,30,0.4
78,807,0.1
1,65,0.02
2,29,0.07
87,1102,0.08
19,2,9.5
18,20,0.9
22,23,0.96
0,1,0
20,417,0.05
29,64,0.45
0,9,0
0,3,0
0,11,0
51,42,1.21
22,17,1.29
15,25,0.6
0,32,0
0,13,0
0,7,0
59,710,0.08
0,20,0
0,25,0
2,77,0.03
0,37,0
174,882,0.2
50,1069,0.05
1,5,0.2
17,10,1.7
0,3,0
0,16,0
3,967,0
8,150,0.05
0,1,0
6,18,0.33
53,122,0.43
0,1,0
42,74,0.57
128,1607,0.08
18,114,0.16
0,1,0
13,31,0.42
50,123,0.41
11,79,0.14
0,28,0
25,106,0.24
106,1197,0.09
4,6,0.67
11,22,0.5
394,213,1.85
4,16,0.25
222,776,0.29
4,468,0.01
0,76,0
3,549,0.01
17,199,0.09
70,2880,0.02
8,396,0.02
0,15,0
14,332,0.04
51,318,0.16
2,515,0
14,1519,0.01
0,78,0
9,326,0.03
11,481,0.02
0,266,0
6,768,0.01
0,8,0
6,519,0.01
2,38,0.05
1,51,0.02
0,7,0
235,2310,0.1
7,521,0.01
0,94,0
3,174,0.02
0,8,0
11,205,0.05
0,4,0
0,15,0
4,40,0.1
0,28,0
75,208,0.36
7,166,0.04
0,15,0
12,143,0.08
0,974,0
160,614,0.26
76,85,0.89
0,39,0
0,121,0
304,699,0.43
50,48,1.04
11,17,0.65
16,211,0.08
2,2,1
140,2138,0.07
0,1,0
6,11,0.55
0,6,0
0,2,0
0,2,0
1,44,0.02
0,65,0
42,2,21
67,198,0.34
98,89,1.1
13,44,0.3
0,1,0
0,2,0
0,6,0
0,1,0
46,231,0.2
22,130,0.17
0,3,0
13,47,0.28
0,1,0
0,2,0
60,304,0.2
543,294,1.85
7,15,0.47
206,475,0.43
1,30,0.03
91,86,1.06
0,15,0
49,98,0.5
9,7,1.29
23,35,0.66
27,449,0.06
5,53,0.09
5,9,0.56
40,134,0.3
0,10,0
0,1,0
13,13,1
150,165,0.91
14,4,3.5
0,7,0
67,48,1.4
0,2,0
2,18,0.11
1,14,0.07
0,6,0
8,765,0.01
20,2860,0.01
1,182,0.01
65,146,0.45
1,86,0.01
0,4,0
0,1,0
0,17,0
0,8,0
3,38,0.08
188,412,0.46
13,1899,0.01
9,855,0.01
0,27,0
1,163,0.01
0,15,0
10,43,0.23
4,22,0.18
17,306,0.06
2,62,0.03
0,3,0
0,106,0
0,26,0
0,53,0
40,15,2.67
2,18,0.11
0,1,0

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