Recent content by tess2

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    Logistic regression in Stata with binomial dependent variable 3-level categorical predictor variable

    Hi, I'm doing a logistic regression analysis with a binomial outcome variable (Yes / No). My main predictor variable is categorical and has 3 levels. I'm also including categorical and continuous confounding variables as predictors. What is the best way to convert my outcome variable from...
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    Choosing a statistical test when study includes both continuous and categorical variables

    Can logistic and linear regression be used when there are both continuous and categorical predictors? Is there any benefit to starting with ANOVA/t-test/chi-square?
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    Can a mixed-effects regression model be used for univariate analysis or just multivariate?

    I'm using a mixed-effects regression model to account for intragroup correlation. Can this be used in both univariate and multivariate analyses?
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    Hierarchical linear modeling - minimum number of observations per group?

    Thanks for the response. It doesn't make much difference (results are still significant), but it does seem the grouping approach is slightly more conservative. I could change incomes to by county (as opposed to by ZIP), which increases observations per group to about 5. Thoughts?
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    Hierarchical linear modeling - minimum number of observations per group?

    I'm looking at the relationship between income and scores on an instrument. Income is estimated by ZIP code. To account for nesting (i.e., people within the same ZIP code sharing an income), I've run a mixed model with ZIP as the random effect. There's a mean of 1.9 observations per ZIP. Is this...
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    Mixed model regression for income by ZIP

    Thank you. I'm a stats-amateur - could you elaborate on how I would do this? I'm using STATA - is there a special "robust" regression analysis to run?
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    Mixed model regression for income by ZIP

    I'm running a regression analysis to understand the impact of income (predictor variable) on scores on an instrument (dependent variable). The only problem is that I don't know each individual's income; I've estimated it using their ZIP code. I've experimented with a few different methods to...
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    Converting a continuous variable into a categorical variable (low, medium, high)

    I have a continuous dependent variable (scores on an exam) and a number of predictor variables that I'd like to use in a regression analysis, such as gender, age, and income. I'd like to convert age and income into categorical variables: low, medium, and high. I'd like to do this using...