where do we fit feasibility study and analysis in SDLC - sdlc

In general the SDLC has the following phase
requirement gathering
design
coding
testing
deployment
but in the above SDLC , where do I fit the below phases ( i know it is around requirement gathering and desing phase)
1) feasibility study
strategic feasibility study ( what we do in this phase?)
technical feasiblility study( what we do in this phase?)
2) Analysis( what we do in this phase ? how is it different from feasibility study ?)
3) modeling

I would say a feasibility study (and proof of concept) happen during requirements gathering and before general design. The purpose is to identify issues that maybe difficult or impossible to implement (technologically, cost, time, etc.), create a subset or manageable chunk of those issues and implement them in a PoC.
Analysis is your more typical phase where you take your requirements and decide what technologies might serve to help realize them. You do things like platform selection, vendor analyses and things of that nature. This is different from a feasibility study in that you're not trying to prove that something is possible, but you're trying to identify implementation decisions you need to make to realize the requirements.

I'm very sure they have provided some textbook for your course in your institute. If they haven't please try reading Roger S. Pressman's "Software Engineering: A Practitioner's Approach". It is really great and insightful book.

I have to design a feasibility study tool, what are the criterias I have to take in to consideratios. Which part of RE is most important to perform feasibility study.

Related

What is the difference between machine learning and deep learning in building a chatbot?

To be more specific, The traditional chatbot framework consists of 3 components:
NLU (1.intent classification 2. entity recognition)
Dialogue Management (1. DST 2. Dialogue Policy)
NLG.
I am just confused that If I use a deep learning model(seq2seq, lstm, transformer, attention, bert…) to train a chatbot, Is it cover all those 3 components? If so, could you explain more specifically how it related to those 3 parts? If not, how can I combine them?
For example, I have built a closed-domain chatbot, but it is only task-oriented which cannot handle the other part like greeting… And it can’t handle the problem of Coreference Resolution (it seems doesn't have Dialogue Management).
It seems like your question can be split into two smaller questions:
What is the difference between machine learning and deep learning?
How does deep learning factor into each of the three components of chatbot frameworks?
For #1, deep learning is an example of machine learning. Think of your task as a graphing problem. You transform your data so it has an n-dimensional representation on a plot. The goal of the algorithm is to create a function that represents a line drawn on the plot that (ideally) cleanly separates the points from one another. Each sector of the graph represents whatever output you want (be it a class/label, related words, etc). Basic machine learning creates a line on a 'linearly separable' problem (i.e. it's easy to draw a line that cleanly separates the categories). Deep learning enables you to tackle problems where the line might not be so clean by creating a really, really, really complex function. To do this, you need to be able to introduce multiple dimensions to the mapping function (which is what deep learning does). This is a very surface-level look at what deep learning does, but that should be enough to handle the first part of your question.
For #2, a good quick answer for you is that deep learning can be a part of each component of the chatbot framework depending on how complex your task is. If it's easy, then classical machine learning might be good enough to solve your problem. If it's hard, then you can begin to look into deep learning solutions.
Since it sounds like you want the chatbot to go a bit beyond simple input-output matching and handle complicated semantics like coreference resolution, your task seems sufficiently difficult and a good candidate for a deep learning solution. I wouldn't worry so much about identifying a specific solution for each of the chatbot framework steps because the tasks involved in each of those steps blend into one another with deep learning (e.g. a deep learning solution wouldn't need to classify intent and then manage dialogue, it would simply learn from hundreds of thousands of similar situations and apply a variation of the most similar response).
I would recommend handling the problem as a translation problem - but instead of translating from one language to another, you're translating from the input query to the output response. Translation frequently needs to resolve coreference and solutions people have used to solve that might be an ideal course of action for you.
Here are some excellent resources to read up on in order to frame your problem and how to solve it:
Google's Neural Machine Translation
Fine Tuning Tasks with BERT
There is always a trade-off between using traditional machine learning models and using deep learning models.
Deep learning models require large data to train and there will be an increase in training time & testing time. But it will give better results.
Traditional ML models work well with fewer data with moderate performance comparatively. The inference time is also less.
For Chatbots, latency matters a lot. And the latency depends on the application/domain.
If the domain is banking or finance, people are okay with waiting for a few seconds but they are not okay with wrong results. On the other hand in the entertainment domain, you need to deliver the results at the earliest.
The decision depends on the application domain + the data size you are having + the expected precision.
RASA is something worth looking into.

How to extract features from fmri?

I'm having fmri dataset for the classification of Normal Controls and Alzheimer diseased patients. Now, as a newbie I'm unable to extract features from my dataset. I want to extract activation patterns, GM,WM, CSF, volumetric measures and hemo-dynamics in numerical form. Please guide me how and where to start from and please suggest some easy and efficient softwares for my work... I'll be obliged...
Take a look at the software packages called FSL (FMRIB Software Library) and SPM (Statistical Parametric Mapping).
Each of them can do the kind of analyses you're asking about. However, be warned that none of these analyses are trivial. You should probably read up a bit on the subject, first. The Handbook of Functional MRI Data Analysis is a great place to start for beginners.
Like #WeirdAlchemy says, these are many analyses you want to carry out, and all of them non-trivial. You typically learn to these over weeks at a relevant intensive course or months during a neuro Masters programme. To answer your question very explicitly:
GM, WM & CSF volumetric measures - You can do this with FSL SIENA, SPM VBM, AFNI 3Dclust, among others.
"Extract activation patterns" is too vague. In all probability, you likely have task-related BOLD fMRI data and want to perform a general linear model (GLM) analysis. FSL FEAT, SPM fMRI, AFNI and others support this. However, without knowing the experimental design, the nature of the data, and what you want to learn from it, it's hard to be more specific about which tool is appropriate.
"Haemodynamics in numerical form" This can mean a number of things, but if you are thinking about the amount of haemodynamic signal modulation (e.g. Condition led to a 2% change in BOLD signal), you get that out of the GLM analysis mentioned above.

The intersection of Machine Learning and Programming Languages fields

While my research area is in Machine Learning (ML), I am required to take a project in Programming Languages (PL). Therefore, I'm looking to find a project that is inclined towards ML.
One intersection I know of between the two fields is Natural Language Processing (NLP), but I couldn't find concrete papers in that topic that are related to PL; perhaps due to my poor choice of keywords in the search query.
The main topics in the PL course are : Syntax & Symantics, Static Program Analysis, Functional Programming, and Concurrency and Logic programming
If you could suggest papers or keywords that are Machine Learning enthusiast friendly, that would be highly appreciated!
Another very important intersection in these fields is probabilistic programming languages, which provide probabilistic inference over models specified as actual computer programs. It's a growing research field, including a recently started DARPA program on this topic.
If you are interested in NLP, then I would focus on two aspects of listed PL disciplines:
Syntax & Semantics - as this is incredibly closely realted to the NLP field, where in most cases the understanding is based on the various language grammars. Searching for papers regarding language modeling, information extraction, deep parsing would yield dozens of great research topics which are heavil related to the sytax/semantics problems.
logic programming -"in good old years" people believed that this is a future of AI, even though it is not (currently) true, it is still quite widely used forreasoning in some fields. In particular, prolog is a good example of language that can be used to reson (for example spatial-temporal reasoning) or even parse language (due to its "grammar like" productions).
If you wish to tackle some more ML related problem rather then NLP then you could focus on concurrency (parallelism) as it is very hot topic - making ML models more scalable, more efficient, "bigger, faster, stronger" ;) Just lookup keywords like GPU Machine Learning, large scale machine learning, scalable machine learning etc.
I also happen to know that there's a project at the University of Edinburgh on using machine learning to analyse source code. Here's the first publication that came out of it

What subjects, topics does a computer science graduate need to learn to apply available machine learning frameworks, esp. SVMs

I want to teach myself enough machine learning so that I can, to begin with, understand enough to put to use available open source ML frameworks that will allow me to do things like:
Go through the HTML source of pages
from a certain site and "understand"
which sections form the content,
which the advertisements and which
form the metadata ( neither the
content, nor the ads - for eg. -
TOC, author bio etc )
Go through the HTML source of pages
from disparate sites and "classify"
whether the site belongs to a
predefined category or not ( list of
categories will be supplied
beforhand )1.
... similar classification tasks on
text and pages.
As you can see, my immediate requirements are to do with classification on disparate data sources and large amounts of data.
As far as my limited understanding goes, taking the neural net approach will take a lot of training and maintainance than putting SVMs to use?
I understand that SVMs are well suited to ( binary ) classification tasks like mine, and open source framworks like libSVM are fairly mature?
In that case, what subjects and topics
does a computer science graduate need
to learn right now, so that the above
requirements can be solved, putting
these frameworks to use?
I would like to stay away from Java, is possible, and I have no language preferences otherwise. I am willing to learn and put in as much effort as I possibly can.
My intent is not to write code from scratch, but, to begin with putting the various frameworks available to use ( I do not know enough to decide which though ), and I should be able to fix things should they go wrong.
Recommendations from you on learning specific portions of statistics and probability theory is nothing unexpected from my side, so say that if required!
I will modify this question if needed, depending on all your suggestions and feedback.
"Understanding" in machine learn is the equivalent of having a model. The model can be for example a collection of support vectors, the layout and weights of a neural network, a decision tree, or more. Which of these methods work best really depends on the subject you're learning from and on the quality of your training data.
In your case, learning from a collection of HTML sites, you will like to preprocess the data first, this step is also called "feature extraction". That is, you extract information out of the page you're looking at. This is a difficult step, because it requires domain knowledge and you'll have to extract useful information, or otherwise your classifiers will not be able to make good distinctions. Feature extraction will give you a dataset (a matrix with features for each row) from which you'll be able to create your model.
Generally in machine learning it is advised to also keep a "test set" that you do not train your models with, but that you will use at the end to decide on what is the best method. It is of extreme importance that you keep the test set hidden until the very end of your modeling step! The test data basically gives you a hint on the "generalization error" that your model is making. Any model with enough complexity and learning time tends to learn exactly the information that you train it with. Machine learners say that the model "overfits" the training data. Such overfitted models seem to appear good, but this is just memorization.
While software support for preprocessing data is very sparse and highly domain dependent, as adam mentioned Weka is a good free tool for applying different methods once you have your dataset. I would recommend reading several books. Vladimir Vapnik wrote "The Nature of Statistical Learning Theory", he is the inventor of SVMs. You should get familiar with the process of modeling, so a book on machine learning is definitely very useful. I also hope that some of the terminology might be helpful to you in finding your way around.
Seems like a pretty complicated task to me; step 2, classification, is "easy" but step 1 seems like a structure learning task. You might want to simplify it to classification on parts of HTML trees, maybe preselected by some heuristic.
The most widely used general machine learning library (freely) available is probably WEKA. They have a book that introduces some ML concepts and covers how to use their software. Unfortunately for you, it is written entirely in Java.
I am not really a Python person, but it would surprise me if there aren't also a lot of tools available for it as well.
For text-based classification right now Naive Bayes, Decision Trees (J48 in particular I think), and SVM approaches are giving the best results. However they are each more suited for slightly different applications. Off the top of my head I'm not sure which would suit you the best. With a tool like WEKA you could try all three approaches with some example data without writing a line of code and see for yourself.
I tend to shy away from Neural Networks simply because they can get very very complicated quickly. Then again, I haven't tried a large project with them mostly because they have that reputation in academia.
Probability and statistics knowledge is only required if you are using probabilistic algorithms (like Naive Bayes). SVMs are generally not used in a probabilistic manner.
From the sound of it, you may want to invest in an actual pattern classification textbook or take a class on it in order to find exactly what you are looking for. For custom/non-standard data sets it can be tricky to get good results without having a survey of existing techniques.
It seems to me that you are now entering machine learning field, so I'd really like to suggest to have a look at this book: not only it provides a deep and vast overview on the most common machine learning approaches and algorithms (and their variations) but it also provides a very good set of exercises and scientific paper links. All of this is wrapped in an insightful language starred with a minimal and yet useful compendium about statistics and probability

Machine learning/information retrieval project

I’m reading towards M.Sc. in Computer Science and just completed first year of the source. (This is a two year course). Soon I have to submit a proposal for the M.Sc. Project. I have selected following topic.
“Suitability of machine learning for document ranking in information retrieval system”. Researchers have been using various machine learning algorithms for ranking documents. So as the first phase of the project I will be doing a complete literature survey and finding out advantages/disadvantages of current approaches. In the second phase of the project I will be proposing a new (modified) algorithm in order to overcome the limitations of current approaches.
Actually my question is whether this type of project is suitable as a M.Sc. project? Moreover if somebody has some interesting idea in information retrieval filed, is it possible to share those ideas with me.
Thanks
Ranking is always the hardest part of any of Information Retrieval systems. I think it is a very good topic but you have to take care to -- as soon as possible -- to define a scope of the work. Probably you will not be able to develop a new IR engine but rather build a prototype based on, e.g., apache lucene.
Currently there is a lot of dataset including stackoverflow data dump, which provide you all information you need to define a rich feature vector (number of points, time, you can mine topics of previous question etc., popularity of a tag) for you machine learning ranking algorithm. In this part of the work you could, e.g., classify types of features (e.g., user specific, semantic feature - software name in the title) and perform series of experiments to learn which features are most important and which are not for a given dataset.
The second direction of such a project can be how to perform learning efficiently. The reason behind is the quantity of data within web or community forums and changes in the forum (this would be important if you take a community specific features), e.g., changes in technologies, new software release, etc.
There are many other topics related to search and machine learning. The best idea is to search on scholar.google.com for the recent survey papers on ranking, machine learning, and search to learn what is the state-of-the-art. The very next step would be to talk with your MSc supervisor.
Good luck!
Everything you said is good and should be done, but you forgot the most important part:
Prove that your algorithm is better and/or faster than other algorithms, with good experiments and maybe some statistics (p-value, confidence interval).
If you do that and convince people that your algorithm is useful you surely will not fail :)

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