Pivot Tables

In the previous lesson we cleaned up the data we’ve been collecting. Now the question is: what can we do with it? Look at this table. It was created from the over 65,000 rows of data in the movie rating dataset we saw a few lessons ago….

	Women		Men
	Number	Avg. Rating	Number	Avg Rating
All Movies	16,716	3.54	48,819	3.53
Star Wars	102	4.23	284	4.37
Abyss, The	20	4.00	82	3.55

How long do you think it would take you to calculate the values in this table from the raw dataset of ~65,000 rows? Justify your answer.

Why make visualizations?

Yesterday you looked at a bunch of data from the Pew Research Center that was all presented visually in graphs and charts. The question is: why? Why did they choose to make a bunch of charts and graphs rather than just showing the raw data itself?

• “Why did Pew Research choose to make a bunch of charts and graphs rather than just showing the raw data itself?“
• “List a few advantages and disadvantages (at least 2 for each) of using visualizations to communicate data”

Google Flu Trends

Read on of the following articles and answer the following question:
“Why did Google Flu Trends eventually fail? What assumptions did they make about their data or their model that ultimately proved not to be true?“

Wired - What Can We Learn from the Epic Failure of Google Flu Trends?
NYTimes - Google Flu Trends: The Limits of Big Data
Nature - When Google got flu wrong
Time - Google’s Flu Project Shows the Failings of Big Data
Harvard Business Review - Google Flu Trends’ Failure Shows Good Data > Big Data

Trends

Last week we started to collect data about ourselves so that we could learn about trends and patterns in our behavior. What is meant by the term "trending"?

Data Collection

Data is all around us. What are some examples of data and give a couple specific reasons as to why someone would collect data.

Intro to Data

The last project you did (Encoding an Experience) was about organizing and structuring digital data to represent complex information. You did it by thinking about bits. In reality we typically don’t have to break digital data down all the way to bits in order to work with it, but understanding that digital data at its root is just bits gives you insights into working with larger data sets. We are about to embark on a new series of lessons where you will work with real data sets and learn how to use to tools to explore and extract information and knowledge from the data. 

But before we do that, what exactly is data? Explain in your own words.

Encode an Experience.

We have come to the end of another unit where we have been building layers of encodings on top of the foundation of bits.


First we learned to develop binary numbers, then ASCII text, then formatted text, and finally color images. High-level encodings are actually quite removed from the underlying bits from which they are made.

What does it mean to encode something?

When we use the term abstraction, what are we referring to?

Lossy Compression

You have been experimenting with how images and files are compressed on a computer and how in turn those files are encoded by the computer. 

• With a partner, go to the Lossy Text Compression App. (Unit 2: Lesson 5)
• Answer the following questions:
• What is happening in the app?
• Should this “count” as text compression?  Why or why not?
• What do you think “lossy” refers to?

Limitations to RGB

Over the last couple of lessons we have been experimenting with RGB color palettes to create different shades of colors while varying the bit sizes of each color. When creating colors on the computer using the pixelation tool, changing the bit size does what? If I wanted to make an image lighter or darker how would you alter the RGB settings? Are there limitations on how light or dark you can go?

RGB Color Model

When we mix RGB colors what are we really doing?

How is mixing paints in real life different than when we mix the colors on the computer using light?
Example: Provided you have a white canvas:
To make white?
To make black?
When you mix red and blue?

Encoding Colored Images

In the previous lesson we came up with a simple encoding scheme for B&W images. What if we wanted to have color?

• Devise an encoding scheme for color in an image file.  How would you represent color for each pixel?  
• How many different colors could you represent?
• Do you have a particular order to the colors?

Encoding Images

Please answer the following:

(K)now: Do you already know something about how images might be encoded?

(W)ant-to-Know:  What would you like to know? What are you wondering about?

Compression Rate

For the last day or so you have been working in Code Studio compressing chunks of text to the achieve the best compression rate possible. Let us test your knowledge.

 

What is the compression rate, or the compressed text size + dictionary size compared to the original text size. (as a percentage)

Is this a “good” compression rate? Why or Why not?

Lossy and Lossless Compression

Compression allows Internet users sending large files to reduce the overall bits and bytes in a file so that it can be transmitted faster over slower internet connections or take up less space on a disk. We have to different types of compression methods, Lossy and Lossless compression. Explain in your own words the difference between these two methods.

Text Abbreviations

When we are texting or sending messages to our friends, many times we never completely type out every single word.


What are some abbreviations for words when sending messages?


Write some examples of things you might see in a text message that are not proper English.


Why do you use these abbreviations?

A+ Presentations

Second day of Presentations and I have to say that those who have presented have definitely set the bar really high for the subsequent students. The problems you outlined, along with your explanations and your connections to real  issues that are happening currently in the news and those issues that you have personally experienced, have exceeded my highest expectations. Job well done! Please ensure that you have posted your flash talks. Now I want everyone to log in and respond to at least one of your classmate's post with a positive remark about something that you really enjoyed about their presentation. Your response should not be generic, but should speak to something that stood out to you or that you can personally relate to.

Presentation Day

You were given three days to research your topic relating to issues facing society in regards to the Internet. From that research you were to choose one thing that stood out to you and prepare a two minute flash talk following specific guidelines. The time is here to demonstrate your knowledge of the Internet thus far. Please publish your flash talk or a link to your talk right after you have presented. Make sure that your link is working before you publish. Good Luck!

Flash Talk

You have been diligently researching your chosen topics and should have zeroed in on the focus of your flash talk. Now it is time to share with your classmates which problem you chose to focus on. Remember that your speech should be approximately two minutes long (roughly 300 words). Follow the guidelines specified in the rubric provided. It is attached to the instructions provided by me. Click here for another copy if needed.  

Net Neutrality, Internet Censorship , Protocol Vulnerabilities and/or Hacks.

You have had a day to begin your research on the topic of your choice. You were given the following to choose from: Net Neutrality, Internet Censorship , Protocol Vulnerabilities and/or Hacks. From your research thus far, what is your understanding of your Topic.

The Internet and Society

There are several issues facing society right now for which it really helps to understand how the Internet functions in order to have an informed opinion.

There are three main issues that we will be focusing on for the end of Unit: Net Neutrality, Internet Censorship , Protocol Vulnerabilities and/or Hacks.

Description

For this project you will prepare a 2-minute “flash talk” related to one of the major issues listed above about the Internet and its effects on people and society. A flash talk is a brief speech or presentation, intended to grab the attention of the audience and convey key information in a quick, insightful, and clear manner.

Purpose

The purpose of this flash talk is for you to demonstrate your knowledge (thus far) of the Internet and how it works, and to connect that to a relevant topic that has an impact on people and society that you care about.

Who is your audience? Not everyone knows as much about the Internet and how it works as you do now. Your speech should be directed at a person (or people) you care about and who you want to inform about this issue. You should provide them with enough technical detail that they can understand why and how it affects them, and the benefits and drawbacks of responses to the issue.

The Internet is for Everyone

“The Internet is for Everyone” is a memo written by Vint Cerf as a plea to the the people who write and define standards to make sure the way the Internet is engineered maintains the philosophy that the Internet should be available and usable by everyone in the world, regardless of race, gender, creed, location, or wealth.  

In the memo, he lays out the state of the Internet and its usage in 2002, predicts the future, and then presents a series of nine challenges or threats to the idea that the Internet is for everyone. The last several paragraphs begin with the phrase: “Internet is for everyone - but it won’t be if… Here is the first sentence from each of those paragraphs

1. Internet is for everyone - but it won't be if it isn't affordable by all that wish to partake of its services, so we must dedicate ourselves to making the Internet as affordable as other infrastructures so critical to our well-being.  

2. Internet is for everyone - but it won't be if Governments restrict access to it, so we must dedicate ourselves to keeping the network unrestricted, unfettered and unregulated.  We must have the freedom to speak and the freedom to hear.

3. Internet is for everyone - but it won't be if it cannot keep up with the explosive demand for its services, so we must dedicate ourselves to continuing its technological evolution and development of the technical standards the lie at the heart of the Internet revolution.   

4. Internet is for everyone - but it won't be until in every home, in every business, in every school, in every library, in every hospital in every town and in every country on the Globe, the Internet can be accessed without limitation, at any time and in every language.

5. Internet is for everyone - but it won't be if it is too complex to be used easily by everyone.  Let us dedicate ourselves to the task of simplifying the Internet's interfaces and to educating all that are interested in its use.

6. Internet is for everyone - but it won't be if legislation around the world creates a thicket of incompatible laws that hinder the growth of electronic commerce, stymie the protection of intellectual property, and stifle freedom of expression and the development of market economies.   

7. Internet is for everyone - but it won't be if its users cannot protect their privacy and the confidentiality of transactions conducted on the network.   

8. Internet is for everyone - but it won't be if parents and teachers cannot voluntarily create protected spaces for our young people for whom the full range of Internet content still may be inappropriate.

9. Internet is for everyone - but it won't be if we are not responsible in its use and mindful of the rights of others who share its wealth.