Let’s explore one of the fundamental concepts of data mining. In the knowledge discovery process there are 7 steps:

  1. Data cleaning
  2. Data integration
  3. Data selection
  4. Data transformation
  5. Data Mining
  6. Pattern Evaluation
  7. Knowledge Representation

What is Data cleaning?

In this step we remove noise and inconsistent data.

What is Data integration?

In this step we decide which data sources will be combined

What is Data transformation?

In this step we consolidate our data. The data is transformed and consolidated into forms appropriate for mining by performing summing or aggregation functions.

What is Data mining?

An essential process where intelligent methods are applied to extract data patterns.

What is pattern evaluation?

In this step we identify the patterns representing knowledge based on interestingness.

What is knowledge representation?

This is the presentation of knowledge to the user for visualization.


Life is harsh. If you want to be successful you better start asking the right questions. I’ve provided a list of questions that will help you learn how to emulate the behaviors of successful people.

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Personal Questions

What was your major?

How did you choose this area of study?

What was your first job in this industry?

How did you get started?

What key experiences shaped your career path?

Which assessments do you use most often?

Why do you prefer one over another?

Can you tell me how you deal with tough projects?

Work/Life Balance

How do you manage your time?

How do you…


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Given a problem, what are you looking for to apply recursion as a technique ? Think of something out of the usual Computer Science (CS) problems. Recursion is applicable in many scenarios beyond CS. What is the difference between Linear and Binary recursion ? Can you convert any recursive pattern to a tail recursion ? What is the point of converting to tail recursion ?

Given a recursion problem, our primary goal is to define a base case. Then we typically try to run through the recursive trace for one call. The most important thing is to identify a base…


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In this post we will explore the difference between a data structure and algorithm. We’ll look at an cooking example from the real world where we implicitly used a “data structure” and an “algorithm”.

Perhaps you’ve wondered can I find the function representing the runtime of a program by executing the program many times with different input size, and plotting the graph ? What does Big-Oh notation give us ?

Finally, given a program with 3 separate for loops, going from 1 to n, where n is the input size. We’ll learn about time complexity.

Then we’ll examine two algorithms…


JavaServer Faces is a (UI) framework for Java web applications and it uses xhtml to render the applications. It is designed to ease the burden of writing and maintaining applications that run on a Java application server and render their UIs back to a target client.

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JSF provides ease-of-use in the following ways:

  1. It provides a simple model for wiring client-generated events to server-side application code.
  2. It also allows custom UI components to be easily built and re-used.
  3. JSF makes the process easy to construct a UI from a set of reusable user interface components.
  4. Simplifies migration of application data…

We can use phpmyadmin to manage our sql database instance. One way to set up phpmyadmin and mysql server 8.0.1 is to use docker.

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Docker is a newer technology that uses the concept of a container to serve applications. To get started you must download docker desktop. I am using a windows machine so I had to configure windows subsystem for linux before I could install docker. After you have docker desktop set up the next steps are very simple. From an administrative powershell prompt we need to run

docker run — name my-own-mysql -e MYSQL_ROOT_PASSWORD=mypass123 -d mysql:8.0.1

then in…


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Let’s describe the differences between client/server interactions in traditional web applications and client/server interactions in Ajax web applications:

Traditional client/server interactions were synchronous. A typical registration form required a user to completely submit a form in a request. Then the request would be processed by the server which would return a response. Ajax, specifically the XMLHttpRequest, object sits in between the client and the server. It allows for asynchronous requests to take place. This is very convenient since we can provide the user with feedback asynchronously. …


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Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable.

  • XML stands for extensible Markup Language
  • XML is a markup language like HTML
  • XML is designed to store and transport data
  • XML is designed to be self-descriptive

Personally, I recognize the importance of xml in the XMLHttpRequest object. For example, the XMLHttpRequest object’s open method is used to create a get request for an XML document at a specified URL. The XMLHttpRequest object is a developers dream, because you can:

  • Update a web page without reloading the page
  • Request data from a server — after the page has loaded
  • Receive data from a server — after the page has loaded
  • Send data to a server — in the background

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What are the similarities and differences between JavaScript, HTML, and Java?

Java, Javascript, and html are similar in that they are used in web development. Each holds it’s respective place. Java is a backend language that runs on the web server via JVM. Javascript however, is runs on the client side. We can use either Java or Javascript to make interactive web pages. When we combine Javascript, Java, and html together we can create a fully dynamic website.

Html is static. We can render a static html page on a browser. Then if we want to add interactive inputs such as event listeners we can add Javascript. If we want to create a fully dynamic website like a student registration page, for example, we can use an html form to post user input to a Java endpoint and process the user data with Java.


What are HTML5 and CSS? How do they interact with each other?

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HTML5 is a markup language that specifies the structure and content of documents that are displayed in web browsers. We use it create front end web pages that show content. HTML5 consists of many elements. Each element contributes to the structure of the page. A form element with a few input elements can be used to collect user information. Then when the user clicks submit the form posts the information to the server page defined in the action attribute of the form element. CSS are styling sheets contribute to the overall look and feel of a website. We can change out different style sheets to give an entirely different feel to a website.

Evan Gertis

I like building technology. That’s pretty much what I live for. http://www.evan-gertis.com/

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