logisitic regression

  1. E

    Adequacy of logit model with oversampled data

    I fitted a binary logit model with unbalanced data which were oversampled using SMOTE. This gave an excellent ROC curve but very poor adequacy - the zero hypothesis of adequacy was rejected by Hosmer-Lemeshow test and le Cessie – van Houwelingen – Copas – Hosmer unweighted sum of squares test...
  2. T

    The same SPSS models give DIFFERENT results

    This absolutely baffles my mind, so I hope you can help me out. I'm doing statistical analyses in SPSS with logistic regression models. I do crude analyses with a single dependent ("A") and a single independent ("B"). Moreover, I do adjusted analyses with a number of additional variables ("X")...
  3. K

    Logit Model_Predictive Regression

    I want to know your mind about one point related to logit regression model. I am using logit model for my analyzing. My key independent variable is the lagged; hence, it is predictive regression. So, my dependent variable is 0 and 1. These 0 and 1 is related to the time of the day. To make it...
  4. D

    Interpret GLM model in test of difference in proportions

    I'm facing the following situation: We conducted a marketing campaign with three groups: 2 test vs 1 of control, where two different type of coupons sent to the two test groups, 3 euros vs. 6 euros. I understand that the best way to test the difference in proportion is a GLM model with binomial...
  5. M

    Forward selection of non significant variables

    Hi, In SAS Enterprise Miner, I trained a logistic regression with forward selection and AIC criteria. I grouped rare levels for categorical variables. One of these variables was selected by the algorithm but the coefficients of all categories were statistically not significant (different...
  6. W

    Multinomial logistic regression

    Hi, I'm quite new to R and I need a little advise on whether multinomial logistic regression is right for what I'm hoping to do for my data. Basically, I've been given some camera trap data to work with. The data is non-normal and consists of 25 species documented over 30 different trap...
  7. G

    Pooled estimate of logistic regression with complex weights

    Hello world, I apologize for not being smarter but here is my question with a bit of a background. I used a multiple imputation method to fill in missing data for a binary outcome that came from survey data. Unfortunately, I found that SPSS does not necessarily come up with a pooled estimate...
  8. 2

    Help interpreting an interaction in Binary Logistic Regression

    Firstly, thank you for taking the time to read my problem that I am having. The goal: interpret the direction of the interaction term. Variables: I have two continuous predictors (heart rate [HR] and pupil dilatation [PD]), predicting a dichotomous outcome (diagnosis of conduct disorder -...
  9. L

    test of logistic regression constant

    Hello, everyone! I wonder whether anyone knows how can i intepret a coefficient of constant in logistic regression. I have used "logistic" in stata, so i got oddsratios. My constant is eqiual .0441026** Please help ! i googled it , but did not find anything.
  10. S

    Logistic regression - how do I interpret Odds ratio & how do I explain a very high OR

    Hello, As part of my doctoral thesis I have completed a logistic regression to assess the impact of some parenting variables on recovery from a diagnosis. I have so far used teaching notes, a variety of text books and the internet to help me analyse the results. I am a clinician foremost and...
  11. F

    Logistic Regression interpretation help

    Hello I'm working on a project and had some debates with my colleagues on logistic regression model. Hope someone here can clarify for us. Let's say this is the model we built: f(x)=a+b1x1+b2X2+e, X1 is awareness of our product, an indicator variable. X2 is number of inquiries, a continuous...
  12. M

    Relationship Test of Paired Data with one variable ordinal, other binomial

    I want to find relationship between a "priority value" and "billable status." The priority value is a numeric value that is an integer in the set of real numbers (can be negative, zero, or positive) The billable status is basically a binomial: either billable or nonbillable. The null...
  13. N

    Conditional logistic regression, multiple testing.

    Hi everyone! I have 10 exposure variables that i would like to analyze univariate. I've applied the conditional logistic regression model to each exposure, univariate, in the program R. I then applied the summary function to each model to get the test statistic, confidence interval and...
  14. C

    Relative bias of estimates of multilevel logistic regression models

    The post is little bit lengthy , but it will give you thorough information and you can run the code easily . Trust me , I believe the answer is really very basic and not lengthy at all . I want to calculate relative bias of estimates of multilevel logistic model with one explanatory...
  15. C

    Penalized quasi-likelihood

    Can anybody explain me why the function `glmmPQL(.)` in `R` behaves in different ways, depending on the number of measurements/individuals you use? To show you this, I generated two examples. The first one includes 20 indivduals with each 100 repeated measurements (binary response), the...
  16. sufeipopo

    How to interpret residual plot of a logistic regression?

    Hi all, I'm working on a default probability model and was modeling the default probability using logistic regression. The pearson residual and deviance residual plots are attached. Can anyone give me some idea about how to interpret these two plots? Do these plots indicate...
  17. S

    Healthcare applications

    I work in healthcare and I was wondering what sort of analytics/modeling projects members of this forum are doing. I guess it would be nice to see how other healthcare institutions are utilizing different tools to solve different problems. I for instance have just embarked on developing a...
  18. E

    Logistic regression, sample sizes and bootstraping

    Hello, this is my first post. I currently I'm working in my phD in a multivariate logistic model but I have a problem regarding the sample size of my observations: -The "success" (1) event group has a sample size of 249 distinct observations - The "non success" (0) event group has a sample size...
  19. M

    Positive chi-square test: what to do next?

    Hi!! I'm analysing two categorical variables, Landslides (YES/NO) and Vegetation (grouped into 18 classes), and I'd like to explore and model the relationship between them. Firstly, I've carried out a chi-square test for independence that has returned a positive result, i.e. the two...
  20. D

    Suggestions for Statistical Methods for Health Research

    I am currently planning a research project looking at a scoring system for patients (using demographics, social circumstances) to determine whether there is a relationship between a patient's score and their length of hospital stay. The score has 5 domains which are all equally weighted so...