A sigmoid function is a mathematical function having an "S" shape (sigmoid curve). Often, sigmoid function refers to the special case of the logistic function defined by the formula S ( t ) = 1 / (1 + e^-t)
Sigmoid function (Wikipedia)
Questions tagged [sigmoid]
256 questions
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Logistic Regression in Sigmoid Data R
Overview
Hello I am working on a project with displaying a "best fit line" over raw data. I have very little statistical experience, so I am unsure what methodologies & functions to pursue. I am also unsure what the general output should be.
I am…
Anthony Hampton
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Sigmoid calibration slope and intercept params
Is there any way to get slope and intercept params for sigmoid calibration?
model_svc = SVC(kernel='linear').fit(X_train, y_train)
model_svc = CalibratedClassifierCV(base_estimator=model_svc, cv="prefit", method='sigmoid').fit(X_train, y_train)
So,…
annaa-ka
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Calculating partial derivatives python
I am little bit confused how to calculate the partial derivatives of sigmoid function in python. Since in general we can calculate that by using the given code:
Example: f(x,y) = x4 + x * y4
w.r.t x. would be then :
import sympy as sym
…
user15675493
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First Derivative of Scatter Plot R
Hello I am working with sigmoidal data and am attempting to plot two scatter plots on top of each other: the raw data & the first derivative of the raw data. My issue doesn't lie in plotting the data, but more-so finding a function that will create…
Anthony Hampton
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1 answer
Using sigmoid on the output of a regression model with normalized data
I'm trying to build a regression model in keras, the input will be a normalized greyscale image, and the output of the model will be a normalized greyscale image too.
I'm aware that a sigmoid at the output is not ideal for regression models since it…
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Interpreting output of a multilabel classification task
I have a MultiLabel Classifier Network which has been trained to predict the affinity of a user towards a fruit. The core assumption is that a person can like more than one fruit hence multiple fruits can be tagged against a person. Therefore the…
akriti
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Adjust sigmoid function parameters
I have a function which consists of 3 linear functions, and looks like that:
The function is defined this way:
t0 = 0.0
t1 = 0.069 #lowest threshold
t2 = 0.17 #highest threshold
t3 = 1.0
y0 = 0.0
y1 = 0.7
y2 = 2.8
y3 = 4
tt = np.linspace(0,…
omri
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doseResponse function MATLAB bad EC50 value
I've been running a variation of the doseResponse function downloaded from here to generate dose-response sigmoid curves. However, I've had trouble with one of my datasets that keeps generating a small EC50 value that visually doesn't appear to be…
user16211698
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Difference between sigmoid function and softmax function
I'm studying classification and regression. But I met some barriers that make me tired.
The first barrier is this:
I heard that the sigmoid function is used for binary classification and the softmax function is used for multi-class classification. I…
CharlesbrownK
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How to fit and plot an smoothed sigmoid function?
I'm trying to fit and plot a sigmoid curve fitted to my data. Here is my code:
import numpy as np
import pyplot
from scipy.optimize import curve_fit
def sigmoid(x, a, b):
return 1.0 / (1.0 + np.exp(-a*(x-b)))
xdata = [ 26457.28874429, …
Marlon Teixeira
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1 answer
doseResponse function MATLAB iteration limit exceeded warning
I've been running a variation of the doseResponse function downloaded from here to generate dose-response sigmoid curves. However, I've had trouble with one of my datasets generating a linear curve instead. By running the following code, I get the…
user16211698
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- 4
0
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1 answer
Logistic function settings in r
After I made a ggplot of my data
I'd like to adjust each curve with a function. I first adjust with nls function, but for the dark blue one, it doesn't work, and it's obvious when we see the curve shape.
So I want to make a logistic function…
Nathan FRIZOT
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1 answer
my nn.sigmoid() gradient different with my manual calculation
so im doing a manual calculation of lstm backpropagation in excel and want to compare it to my code, but im having trouble with the gradient of sigmoid at the pytorch. :
the output here:
tensor([[0.8762]],…
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1 answer
Sigmoid activation output layer produce Many near-1 value
:)
I have a Datset of ~16,000 .wav recording from 70 bird species.
I'm training a model using tensorflow to classify the mel-spectrogram of these recordings using Convolution based architectures.
One of the architectures used is simple multi-layer…
Ronen
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Input 0 of layer "sequential" is incompatible with the layer: expected shape=(None, 223460, 5), found shape=(64, 5)
I'm trying to make a binary Classification by combining CNN (con1D) with GRU. my dataset dataset is like that :
X_train shape : (223461, 5)
y_train shape :(223461,)
the X_train is like that and the Y_train is a labels (0,1) like that
first I…
MexcelsiorB
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