logistic regression Definition and 14 Threads

If some variables of a logistic regression models are non significant, should they be considered for a risk index calculation? Should the logistic model include only relevant variables? Thanks for the attention.

Hi I am trying to remember the name of the situation in logistic regression when all data points beyond a fixed one are all successes or all fails. So we have data points## ( a_{i1}, a_{i2},.., a_{in} , 0/1) ##, with data points ##a_{ij}##ordered; last input a Boolean and a fixed value for j...

I have a simple dataset that consists of one predictor Sex and one response variable Survived. Let's say the estimated coefficients are ##\hat{\beta_0}## and ##\hat{\beta_1}## for the intercept and the coefficient of Sex predictor, respectively. Mathematically this means that: \hat{p}(X) =...

I was trying to find an easy interpretation of the predicted probabilities of a logistic regression model, when one of my coworkers claimed that the logistic regression model is a likelihood. Now, I know that maximum likelihood estimation is used to estimate the parameters, but I didn't think...

Hi all, I have logistically- regressed 3 different numerical variables ,v1,v2,v3 separately against the same variable w . All variables have the same type of S-curve (meaning, in this case, that probabilities increase as vi ; i=1,2,3 increases ). Is there a way of somehow joining the three...

Hi all , just curious if someone knows of any issues of Separation of Points in Ordinal 3-valued Logistic Regression. I think I have an idea of why there are issues with separation in binary Logistic -- the need for the S-curve to go to 0 quickly makes the Bo term go to infinity. Are there...

Hello, I remember an example of application of the logistic regression to medicine / epidemiology, which said (more or less) that the probability of a person having miocardial infarction was related to some variables such as age, cholesterol level, etc, and the equation included the various...

So I've been following through a online course in machine learning offered by Stanford university. I have been recently reading up on logistic regression and stochastic gradient ascent. Here is a link to the original notes: http://cs229.stanford.edu/notes/cs229-notes1.pdf (pages 16-19). Here...

I am doing an independent research project and I have written a logistic regression program in SAS. The percent concordance is 97%, but hardly any variables are significant. Can anyone help me understand why this would happen?

I am doing some research and running a SAS program using logistic regression. The concordance is 99%, but hardly any variables are significant. Can anyone help me understand what this means?

Hi, I am studying logistic regression and gradient ascent and have seen it used with a cost function and without one. Could anyone tell me why you would use a cost function? It seems just as effective without one. alpha = .05 h = data * weights error = labels - sigmoid(h)...

To determine whether schools are increasing the amount of students meeting or exceeding standards, I obtained a MEAP database reporting the amount of students that scored in the met or exceed standards range during years 2005-2009, for grades 3-5. I then graphed the data for using numbers...

Hi Is it possible to use both dummy variable regressors as well as categorical response variables in the same model? Consider the following model from cricket (you don't need to know the game to answer this question): Y = mode of dismissal (0 = not out, 1 = bowled, 2 = caught, 3 =...

Hello all, I've performed a simple logistic regression and could use some help in interpretations/minor calculations. Five different doses of insecticide were applied under standardized conditions to samples of an insect species. The data were: Dose: ---2.6---3.8---5.1---7.7---10.2--- Dead...