Tagged Questions
1
vote
0answers
20 views
sklearn setting learning rate of SGDClassifier vs LogsticRegression
As in sklearn, LogisticRegression(short for LR) has not direct method for solving weighted LR, so i pass to SGDClassifier(SGD).
As with my experiment: i generate data follow LR distribution with ...
0
votes
2answers
44 views
Is there a way to implement sample weights in python logistic regression?
I'm using statsmodels for logistic regression analysis in python
e.g.:
import statsmodels.api as sm
import numpy as np
x = arange(0,1,0.01)
y = np.random.rand(100)
y[y<=x] = 1
y[y!=1] = 0
x = ...
2
votes
0answers
23 views
Creating a sklearn.linear_model.LogisticRegression instance from existing coefficients
Can one create such an instance based on existing coefficients which were calculated say in a different implementation (e.g. Java)?
I tried creating an instance then setting coef_ and intercept_ ...
1
vote
1answer
29 views
sklearn.linear_model.LogisticRegression returns different coefficients every time although random_state is set
I'm fitting a logistic regression model and am setting the random state to a fixed value.
Every time I do a "fit" I get different coefficients, example:
...
1
vote
0answers
36 views
Error with Simple Logistic Regression in Python
import numpy as np
import matplotlib.pyplot as plt
class Logistic_Regression(object):
def __init__(self, input):
self.data = np.loadtxt(input, delimiter=',')
self.x = ...
-1
votes
1answer
24 views
Python SK Learn: Is it posible to feed several sets of data to “SGDClassifier” from sk learn to update parameters
I'd like to split my data set in to a little chuck due to limitation of my software and feed to Stochastic Gradient Descent (SGD) Logistic-Regression. Is it possible to do this in "SGDClassifier" ...
0
votes
1answer
56 views
How to use scikit-learn to predict the rate of change in a site's hit counts
I want to predict the change in hit counts for a website using the rate of change. For example, if a site's hits double in a day (from 5,000 to 10,000), the rate of change is 2. If the hits go up by a ...
2
votes
0answers
31 views
Implementing a regression function on a multidimensional array
I'm going through an algorithm that does regression on some training data.
The training dataset X consists of n samples, where n = 10.
Each sample x[i] from X is an array consisting of, say, 4 ...
6
votes
1answer
113 views
What is the inverse of regularization strength in Logistic Regression? How should it affect my code?
I am using sklearn.linear_model.LogisticRegression in scikit learn to run a Logistic Regression.
C : float, optional (default=1.0) Inverse of regularization strength;
must be a positive float. ...
0
votes
1answer
28 views
Categorical variable in Rpy2 (factor function)
How can I do this in rpy2?
mydata is a dataframe and rank is a varaible from 1 to 4
mydata$rank <- factor(mydata$rank)
5
votes
1answer
170 views
Why can't statsmodels reproduce my R logistic regression results?
I'm confused about why my logistic regression models in R and statsmodels do not agree.
If I prepare some data in R with
# From https://courses.edx.org/c4x/MITx/15.071x/asset/census.csv
...
0
votes
0answers
59 views
Include all binarized dummies of categorical variable in logistic regression (scikit-learn)?
For each categorical (nominal) variable I created a set of binary dummies.
Is it OK to throw the whole dummy set into scikit-learn's logistic regression or should I exclude one dummy of each set in ...
0
votes
2answers
138 views
Dummy Variables in Python SKLearn Logistic Regression
I am using logisitic regression in SKLearn to classify data into one of 5 classes. To train the data I have a matrix of observations Y and a matrix of features X.
Sometimes it is the case that my ...
2
votes
3answers
78 views
Software for Image classification
Currently I am working for a project to classify a given set of test images into one of the 5 predefined categories. I implemented Logistic Regression with a feature vector of 240 features for each ...
1
vote
2answers
88 views
How to make sure that solution is global minimum while using python scipy.optimize.minimize
I was implementing logistic regression in python. To find theta , I was struggling to decide which is the best algorithm that always guarantees global optima without bothering about initial parameter ...
1
vote
1answer
107 views
Speeding up sklearn logistic regression
I have a model I'm trying to build using LogisticRegression in sklearn that has a couple thousand features and approximately 60,000 samples. I'm trying to fit the model and it's been running for ...
1
vote
1answer
945 views
Features in sklearn logistic regression
I have some problem with adding own features to sklearn.linear_model.LogisticRegression. But anyway lets see some example code:
from sklearn.linear_model import LogisticRegression, LinearRegression
...
0
votes
1answer
254 views
Python SKLearn: Logistic Regression Probabilities
I am using the Python SKLearn module to perform logistic regression. I have a dependent variable vector Y (taking values from 1 of M classes) and independent variable matrix X (with N features). My ...
1
vote
1answer
1k views
Logistic regression using python
I want to implement Logisitic regression from scratch in python. Following are the functions in it:
sigmoid
cost
fminunc
Evaluating Logistic regression
I would like to know, what would be a ...
0
votes
1answer
331 views
How do I plot the decision boundary of a regression using matplotlib?
How do I add a countour map of the results of the logistic regression to my scatterplot? I want colored 0/1 zones, which delineate the decision boundary of the classifier.
import pandas as pd
import ...
1
vote
1answer
152 views
python transform a string input matrix to 0-1 binary input matrix for logistic regression like R [duplicate]
I'm doing some logistic regression with Python using pandas+numpy+scikit-learn. However in scikit-learn build-in logistic regression model, it doesn't allow a string input, but I'd like to do ...
0
votes
1answer
478 views
GridSearchCV on LogisticRegression in scikit-learn
I am trying to optimize a logistic regression function in scikit-learn by using a cross-validated grid parameter search, but I can't seem to implement it.
It says that Logistic Regression does not ...
0
votes
1answer
626 views
Scikit Learn: Logistic Regression model coefficients: Clarification
I need to know how to return the logistic regression coefficients in such a manner that I can generate the predicted probabilities myself.
My code looks like this:
lr = LogisticRegression()
...
