logistic

  1. R

    How to find importance of an independant variable on a binary variable

    I am trying to learn statistics to help with my understanding of data I am getting in for the business I work for. I have a variable on whether someone left or are still customers. I have this listed as 0 or 1. I have a variable that is the variance of the customers last 8 months. I see...
  2. A

    Logistic Regression

    Could someone explain the basics of logistic regression? Thank you!
  3. S

    Logit Model - technique to eliminate covariates

    I have a model to build that employs a reference table of 5000 standard covariates that are transformed by the intersection of that reference table with the actual data table. These are mostly CATEGORICAL covariates. Better yet, they are BINARY ("Yes","No" or 1,0). The software I use only allows...
  4. K

    What type of distribution is this and am I being sensible?

    I have a computer model, which I need to run 3500 times with different input parameters. The model's accuracy depends on a constant, let's call it T, which unlike the input parameters doesn't change between model runs. By decreasing T, the model's accuracy improves but the computational cost...
  5. B

    STATA to SAS: survey logistic regression

    I am getting very different coefficients and p-values with STATA and SAS. It would be great to figure out which program is set up wrong. My sampling weights variable is samp_wt. My cluster variable is sta3n. My binary response is Screened. STATA: svyset sta3n [pweight=samp_wt] svy: logit...
  6. A

    Binary Logistic Regression Output missing some Sig values

    I am running a Binary Logistic Regression on: - A numeric Fixed Factor as the dependent variable (two levels) - 3 numeric Fixed Factors as independent variables (two levels each) - 6 numeric Covariates as independent variables On my output, the Likelihood Ratio Tests table gives me...
  7. R

    Graphing Logistic Regressions in Stata

    Hi all, I'm testing for slope/threshold (intercept bias). My Y variable is dichotomous (past suicide attempt, yes/no) and my predictor variable, X1, is dichotomous (gender) and the other, X2, is continuous (scores on a test). Intercept bias is occurring with my X1 predictor variable, and I...
  8. R

    Explanatory logistic regression model

    Hello, I would like to fit an explanatory logistic regression model. In this case, when I am not interested in forecasting or predicting, is it possible to not to pay attention to a residuals analysis? What is the most important to check in this only explanatory case? Thank you very much...
  9. R

    Interaction Terms: Logistic Regression

    Dear forum, trying again... I would really like some advice on the proper construction and interpretation of a small experiment and analysis using Logistic Regression. I had a sample of 50 people evaluate three different products (X1) and generate a score (X2). Then they indicated how...
  10. P

    Factor analysis, what type of data can I use?

    Hello everyone, I have a social science dataset composed of circa 40 variables. The data types I am using are quite diverse. The variables I am using (briefly put) are: are age, gender, educational background(1-7 scale), 7 point perception scales measuring the degree of trust in...
  11. K

    graphical data exploration with categorical predictor variables&binary response varia

    Dear all, I have a rather complicated dataset of behavioral observations and would be very grateful if you could help me with some advice. I am looking for the best way to do an exploratory data analysis and to greate useful graphs of my data. My dataset deals with yes/no observations on...
  12. F

    Binomial Logistic Regression - Predicted Probabilities

    Hi. I’m taking my first steps on binomial logistic regression and I was hoping you could help me with some doubts I’m having. My model has a single independent variable: liking party, scaled 0-10. My dependent variable is vote for that party (0 = no; 1= yes). Apart from those, I’m splitting my...
  13. R

    Interpretation of Binary Logistic regression with confounder

    I simplified it a bit so I can get my question across easier Dep variable: Happy(0) or Sad(1) Independent variable: Age Independent V: Sent to Facility: farm T (1) or Ranch K (0) Note: There was bias and the more of the oldest of patients were sent to Farm T. I get these values using SPSS...
  14. M

    Interaction effect in a logistic regression between cont and cat variables.

    Hi guys, I am conducting a logistic regression on whether a participants test positive or not to HIV (1=positive; 0 Negative) in a sample of transgender people. I have two independent variables Sw sex workers (yes or not) and number of sex partners (NsexP). When I run the logistic...
  15. T

    Number of variables that can be included in an exact logistic regression

    I'm currently analyzing a dichotomous outcome using a small dataset of only 100 individuals. the outcome occurs in only 25 individuals and I have some predetermined confounders that I would like to adjust for. I know that I am limited by, at most, 2-3 variables if I were to model using a...
  16. A

    Which test to compare two curves

    I have used a stimulus (stimulus1) in a perception test, to see if the participants perceive it as A or B in a forced choice task. (the stimulus is composed of several features f1,f2...) Then I have changed one of the features (f1) of stimulus1 gradually in 5 different levels. All...
  17. M

    Logistic regression detection of multicollinearity- is VIF applicable?

    I have a model with a dichotomous DV and IVs both continuous/numerical and dichotomous. I checked for collinearity with Pearson. How do I check for multicollinearity in logistic regression? Could I follow the procedure of rotating my IVs as DVs one at a time against the remaining IVs, and...
  18. jpkelley

    Variation in inflection point for modeled logistic curve

    Hey all. Question category: R and regression; Posted in R forum since R code. Question: How best to quantify variation in an inflection point for a logistic curve? Background of problem: Birdies begin their birdie lives contained in eggs. Then, they hatch and continue their lives...
  19. B

    Conditional expectation

    Good afternoon, I have to calculate the expected value of a logistic distribution given that the values are above a given constant (lets say 0). So far I have done it numerically by programming a generator of random numbers coming from a logistic distribution and then taking the average of those...
  20. R

    Logistic Regression / Weight of Evidence Transformed Variables

    Hi Everyone, I'm looking for some help to interpret the output of logistic regression when using predictors that have been transformed and binned using the Weight of Evidence procedure. Specifically, how does one interpret a significant coefficient and corresponding odds ratio? For...