Sigmoid units, Computer Engineering

Assignment Help:

Sigmoid units:

Always remember that the function inside units take as input the weighted sum, S and of the values coming from the units connected to it. However the function inside sigmoid units calculates the following value that given a real-valued input S: is as

2248_Sigmoid units.png

Whereas e is the base of natural logarithms, e = 2.718... 

Where we plot the output from sigmoid units given various weighted sums as input that looks remarkably like a step function as: 

983_Sigmoid units1.png

Obviously by getting a differentiable function that looks like the step function was the whole point of the exercise. Moreover, not only is this function differentiable but  there the derivative is fairly simply expressed in terms of the function itself as: 

970_Sigmoid units2.png

So note that the output values for the σ function range between but never make it to 0 and 1. It means that e-S is never negative so the denominator of the fraction tends to 0 as S gets very big in the negative direction and then tends to 1 as it gets very big in the positive direction. In fact this tendency happens fairly quickly as: in the middle ground between 0 and 1 is rarely seen means the sharp or near step in the function. Just because of it looking like a step function that we can think of it firing and not-firing as in a perceptron as: if a positive real is input and the output will generally be close to +1 then a negative real is input the output will generally be close to -1.


Related Discussions:- Sigmoid units

Macroscopic and microscopic approaches - thermodynamics, Macroscopic and Mi...

Macroscopic and Microscopic approaches - Thermodynamics: Thermodynamic studies are undertaken by following two different approaches.  l. Macroscopic approach (Macro mean big)

Weka uses a gaussian - radial basis function, A data set with 1000 rows is ...

A data set with 1000 rows is input to a neural network in Weka. The test option is set to 10-fold cross validation and the neural network option validationSetSize = 20%. How many r

What are event and its types, What are event and its types? An event is...

What are event and its types? An event is an occurrence at a point in time, like user depresses left button. Event happens instantaneously with regard to time scale. Type

What is the difference between awt and swt, SWT (Standard Widget Toolkit) i...

SWT (Standard Widget Toolkit) is a totally independent Graphical User Interface (GUI) toolkit from IBM. They formed it for the creation of Eclipse Integrated Development Environmen

Associative array processing, Associative Array Processing Consider tha...

Associative Array Processing Consider that a list of record or a table is stored in the memory and you want to search some information in that list. For example, the list havin

Explain signed binary number system, Explain signed binary number system. ...

Explain signed binary number system. Ans. Signed Binary Numbers: In decimal number system positive numbers are signified by (+) sign and negative numbers are represented b

Reprography of information distribution, Reprography In order to dissem...

Reprography In order to disseminate information widely some method of reprography is invariably used. Reprography is the science and practice of copying documents by photograph

Cohesion and coupling, can i get a prepared ppt for this topic to present i...

can i get a prepared ppt for this topic to present it in a seminar??

Give example of stack using encapsulation of OOA, Give example of stack usi...

Give example of stack using encapsulation of OOA An example of the Stack.  A Stack abstraction provides methods like pop (), push (), isEmpty(), isFull(). The Stack can be i

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd