[R] Zero inflated: is there a limit to the level of inflation

[SSimek]

Hello, 

I have count data that illustrate the presence or absence of individuals in
my study population. I created a grid cell across the study area and
calcuated a count value for each individual per season per year for each
grid cell. The count value is the number of time an individual was present
in each grid cell.  For illustration my data columns look something like
this and are repeated for each individual:

Cell_ID	Param1	Param2	Param3	Param4	COUNT	Name	Year	Season	Cov
1	160.565994	729.08	1503	7930.3	0	AA	2010	AUT	Open
1	160.565994	729.08	1503	7930.3	22	AA	2011	SPR	Open
1	160.565994	729.08	1503	7930.3	12	AA	2009	SUM	Open
1	160.565994	729.08	1503	7930.3	0	AA	2010	SUM	Open
2	169.427001	491.87	1503.31	5101.09	0	AA	2010	AUT	oldHard
2	169.427001	491.87	1503.31	5101.09	16	AA	2011	SPR	oldHard
2	169.427001	491.87	1503.31	5101.09	0	AA	2009	SUM	oldHard
2	169.427001	491.87	1503.31	5101.09	0	AA	2010	SUM	oldHard
…									
563	86.777099	612.69	977	4474.6	62	AA	2010	AUT	Water
563	86.777099	612.69	977	4474.6	12	AA	2011	SPR	Water
563	86.777099	612.69	977	4474.6	55	AA	2009	SUM	Water
									
									
1	160.565994	729.08	1503	7930.3	0	BB	2010	SUM	Open
2	169.427001	491.87	1503.31	5101.09	72	BB	2010	SUM	oldHard
5	160.75	614.95	1503.31	2878.98	16	BB	2010	SUM	medHard
6	170.404998	510.58	1489.44	743.14	0	BB	2010	SUM	Water
…									
563	86.777099	612.69	977	4474.6	0	BB	2010	SUM	Water
									
									
1	160.565994	729.08	1503	7930.3	14	C	2005	AUT	Open
1	160.565994	729.08	1503	7930.3	0	C	2006	AUT	Open
1	160.565994	729.08	1503	7930.3	0	C	2006	SPR	Open
1	160.565994	729.08	1503	7930.3	56	C	2007	SPR	Open
1	160.565994	729.08	1503	7930.3	0	C	2006	SUM	Open
2	169.427001	491.87	1503.31	5101.09	124	C	2005	AUT	oldHard
2	169.427001	491.87	1503.31	5101.09	231	C	2006	AUT	oldHard
2	169.427001	491.87	1503.31	5101.09	889	C	2006	SPR	oldHard
2	169.427001	491.87	1503.31	5101.09	0	C	2007	SPR	oldHard
…									
563	86.777099		612.69	977	4474.6	0	C	2005	AUT	Water
563	86.777099		612.69	977	4474.6	231	C	2006	AUT	Water
563	86.777099		612.69	977	4474.6	185	C	2006	SPR	Water
563	86.777099		612.69	977	4474.6	123	C	2007	SPR	Water
563	86.777099		612.69	977	4474.6	52	C	2006	SUM	Water



I have 563 grid cells across my study area and each individual has 1-563
cells associated for each year and each season the individual was monitored.
Therefore my grid cells are repeated. I end up with 71,000 records and 925
records have a Count value >0; which means 70,075 records have a Count value
= 0. 

I wanted to run a zero inflated poisson model to determine mixed effects (of
parameters) with individual as the random effect. But I have been advised
two things:

1. I cannot run a zero inflated poisson model because my data are too
"extremely" inflated (i.e. 70,075 vs 925) and 

2. I cannot run the model with each cell repeated for each individual. I am
told the model doesn't recognize that Cell_ID #1 for individual "A" is the
same Cell_ID #1 for individual "B".

Does anyone know if either or both of these points are true? I would
appreciate any thoughts, advice, or suggestions. 

Thanks!

-Stephanie

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