search for: purban2

Hi. I'm trying to plot the ratio of used versus unused bird houses (coded 1 or 0) versus a continuous environmental gradient (proportion of urban cover [purban2]) that I would like to convert into bins (0 - 0.25, 0.26 - 0.5, 0.51 - 0.75, 0.76 - 1.0) and I'm not having much luck figuring this out. I ran a logistic regression and purban2 ends up driving the probability of a box being occupied so it would be nice to show this relationship. I'm also...

Dear R-users, I did some more research and I'm still not sure how to set up an ANCOVA with nestedness. Specifically I'm not sure how to express chicks nested within boxes. I will be getting Pinheiro & Bates (Mixed Effects Models in S and S-Plus) but it will not arrive for another two weeks from our interlibrary loan. The goal is to determine if there are urbanization (purban)

...ooks to be coded exactly the same way. Looking at the output, I get estimates for each case when I should get a single estimate for purbank. Any suggestions? Many thanks, Jeff THE DATA: (200 boxes total, used [0 if unoccupied, 1 occupied], the rest are landscape variables). box use purbank purban2 purban1 pgrassk pgrass2 pgrass1 grassdist grasspatchk 1 1 0.003813435 0.02684564 0.06896552 0.3282487 0.6845638 0.7586207 0 3.73 2 1 0.04429451 0.1610738 0.1724138 0.1534174 0.3825503 0.6551724 0 1.023261 3 1 0.04458785 0.06040268 0 0.1628043 0.557047 0.7586207 0 0.9605769 4 1 0.06072162 0.2080537...

I just had a manuscript returned with the biggest problem being the analysis. Instead of using principal components in a regression I've been asked to analyze a few variables separately. So that's what I'm doing. I pulled a feather from young birds and we quantified certain aspects of the color of those feathers. Since I often have more than one sample from a nest, I thought I