Hello,

I think there is a problem there.

You have Day and Month and Hour as independent random factors.

This means you assume that the first of January, the First of March and the First of June have something in common.

The same thing is true for Hour, so you assume implecitely a daily patter. You did not provide enough information to say what is the right way of analysing it. Usually I woudl suggest to make a variable called time from month, day and possibly hour values. Because it is a class variable this makes only sense if you measure several points at the same time (like the same hour).

You should also think that season can be confounded with the month effect.

Frank

On 21.5.2019 20.41, Manuel Spínola wrote:
Dear list members,

Sorry for cross-posting.

I measured an index on 12 points within each of 3 cover types on 4 seasons.

But the index was measured several times within hours, on different days
and different months.

I want to assess changes in the index among cover types and seasons.

Is the following model parameterization appropriate in the lme4 package:

mod_adi_01 <- lmer(ADI ~ Season*CoverType + (1 | Point) + (1 | Month) + (1
| Day) + (1 | Hour), data = df_01, REML = FALSE)

Manuel



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