Recent content by MayTrix

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    Beta Regression?

    The sample size is 28 observations (very small). One suggestion I have had is to run two-stage or two-part models that can be used for data with excess zeros. That has led me to look at running a Zero-inflated Poisson regression. It is used to model count data that has an excess of zero counts...
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    Beta Regression?

    Actually, the mean value of the data is 0.1128, 25% of the data lies between .2 - 0.8 and 28% is missing. Any suggestions?
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    Beta Regression?

    Dason - The dependent variable is a count of a certain type of cell divided by the total number of cells. Let me now if you need more details! Thanks!
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    Beta Regression?

    Hi, I have a response variable that lies between 0 and 1. It is a proportion. My dependent variables are categorical. Normally, I would run a two-way ANOVA but, in this case, would it be okay to run a beta regression? Or is there a two-ANOVA equivalent that I can run? Thanks
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    Starting Values for a non-linear regression

    Hi I am trying to get the starting values for non-linear regression of a data set that follows a weibull function. I tried to do the OLS regression of this equation: log(log(1-F(t)))=-Beta(log(lambda))-Beta(log(t)) to get the starting values. The only problem is that F(t) is greater than 1...
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    Comparing two non-linear models

    I have a non-linear model and I would like to determine if there is a difference between two treatments. Would it be robust to add in treatment as a dummy variable into the model. Where a value of 1 would represent treatment A and a value of 0 would represent treatment B. Then if the treatment...
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    cross-tabs or non-parametric independent sample t-test

    I have conducted a survey to determine if there is a significant difference in the number farmers and non-farmers which agree to a specific farming policy. I have two variables. One variable identifies if the survey respondent is either a farmer or not. The other variable is binary and will...