This is CS50 on Twitch.

My name is Colton Ogden, and today I am joined for the first time by--

ANDY CHEN: Andy Chen.

Nice to meet y'all.

COLTON OGDEN: So Andy here--

tell us a little about what would you do here

on campus, which you're involved in.

ANDY CHEN: Sure.

So I am a master student studying bioinformatics.

I'm also a special student in computer science,

and I actually work at HarvardX, so if you guys

are familiar with the online learning platforms of Harvard, that's

one of the offices that has really good resources.

COLTON OGDEN: I feel like you--

didn't I-- I met you in the spring, I think.

You came to the fair for the Supreme Court.

ANDY CHEN: That's right, yeah.

COLTON OGDEN: And I think you were talking

about something like that, yeah.

Pretty exciting.

And what are you going to talk about today?

ANDY CHEN: Well today we're going to talk about a programming

language called R, and one of the things you

can do in it which includes biostatistics.

COLTON OGDEN: Oh yeah.

ANDY CHEN: Cole, you might ask me what is biostatistics?

COLTON OGDEN: What is biostatistics?

I actually--

ANDY CHEN: So it's really statistics in the field of like biological data.

But a lot of people use it in the context of epidemiology,

as opposed to more like molecular biology kind of things.

And that's actually what we're going to be dealing with today.

COLTON OGDEN: That's diagnosing diseases, right?

Epidemiology.

ANDY CHEN: Epidemiology is sort of the study

and the practice of response to the spread of diseases.

COLTON OGDEN: Got it, OK.

Makes sense.

ANDY CHEN: Right.

COLTON OGDEN: I clearly don't--

I'm not an expert on biology or biostats.

ANDY CHEN: But you will be soon.

COLTON OGDEN: Yeah, I'm very excited.

We have a lot of people in the chat that have joined us,

and were talking before we started a little bit in advance.

Thank you very much to everybody who's joined.

Regulars of ISO TV.

There's a new regular, Asley, Newanda33333, belacures,

m.kloppenburg, thank you for joining.

Let me make sure I didn't miss anybody up above that.

Techytack, hello.

[INAUDIBLE] and fatma, thank you for joining

the regulars and everyone she's saying.

Really curious about about this one says m.kloppenburg.

This is the first time we've had anything kind of statistics

related onstream.

ANDY CHEN: Oh, exciting.

COLTON OGDEN: Python's obviously a language

that's very often used in bio or in stats, generally speaking.

But R kind of like the language that people I think, maybe most people

associate-- or at least they associate starts with R, and then R also

sort of with stats that end with Python, too.

I don't know anything about R, so I'm actually

very curious to see what it looks like, what the environment looks,

what we can do in it.

I think we've caught up on all the comments.

Everybody's saying hey Andy, nice to meet you Andy, everybody saying,

so you got a lot of friends in the chat there.

Yeah, so thanks so much everybody.

Let's go to your screen here, so we have your screen set up.

And why don't you get us started here.

ANDY CHEN: Sure, awesome.

Thank you very much Colton.

Hello everyone, hello friends from all over the world.

So R, like Colton was saying, is one of probably two languages

that are very popular for statistics or data science kind of things,

Python being the other one.

Today we're going to be looking at R, which let's go to the website.

So bring up a browser if you will.

The first thing we're going to be doing is installing the language itself.

Now notice that we actually are not going

to be working in R, which on Mac OS 10--

well actually I don't know what I'm running,

but whatever-- on Mac you have to install R the language itself,

which actually I think does have a command line interface.

But we're going to be working in R Studio, which

is an integrated developing--

developing environment?

COLTON OGDEN: Integrated development environment.

ANDY CHEN: Development environment, thank you.

COLTON OGDEN: It's a mouthful.

ANDY CHEN: It's a mouthful.

I'll just keep calling ID.

COLTON OGDEN: ID.

That's why we call it an ID.

No one wants to say all those words.

ANDY CHEN: But yeah, so we're going to be installing

R, which is the language itself, as well as R Studio, which

is the IDE in which we'll be working.

COLTON OGDEN: What are the links that we can go to,

and I can toss them in the chat as well.

ANDY CHEN: Great So the first one is going to be www.r-project.org.

COLTON OGDEN: OK.

ANDY CHEN: The second one is going to be rstudio.com.

And the last one--

COLTON OGDEN: The former being the language

itself, the latter being the IDE, the R IDE that you're alluding to?

ANDY CHEN: Exactly.

COLTON OGDEN: OK.

And babicnight also in the chat, and Andre Jacob Johnson, and Irenae,

thank you very much for joining us, everybody.

Well, some more regulars.

And babic, to answer your question, not late at all.

We just started.

We're now tossing in some links into the chat for downloading R and RStudio.

So r-project.org and rstudio.com.

ANDY CHEN: Thank you.

So what we're going to be doing today is working

with the M Heinz data set, which is actually kind of difficult to--

it's freely available.

It's a US governmental data, but it's actually hard to parse its raw format,

so what we have provided today is a .text file,

which I've uploaded to this link.

I don't--

COLTON OGDEN: We can make a bitly for it.

So what is the--

do you want to email me the link, and then I'll toss a bitly into the chat.

People can click on it, and then get access to it later on YouTube.

ANDY CHEN: Absolutely, yep.

And then so while I'm doing that, let's see.

Let's get to email.

Oh, man [INAUDIBLE] piling up.

COLTON OGDEN: If you want I can go and go here,

so people can see your personal email.

ANDY CHEN: Oh, yeah.

Some people like that.

COLTON OGDEN: Lots of juicy tidbits in there.

Everybody just go ahead and look through Andy's email.

Yeah, we'll get to it we'll get a bitly for everybody in the chat,

if you want to email that to me.

ANDY CHEN: I think it should be sent.

COLTON OGDEN: OK, and we refresh.

Just one sec, everybody.

Sorry for the delay, but this will be a lot better than typing

a super long mega upload link.

OK, so here I go I got the link.

I'm making the link.

I'm going to copy it to bitly.

If it wants to cooperate.

Copy it over to bitly, paste it in there.

Get rid of these stupid messages.

ANDY CHEN: They're just try to show you love, Cole.

COLTON OGDEN: A little bit.

Aw, crap.

OK.

Here, we're good.

We got this.

And edit bitly, get a a copy.

Can customize it?

I can't.

So we're going to call this bit.ly/biostats_stream.

And so that will be how it works.

Clear all these messages, save that.

It's going to-- I'm going to copy that.

I'm going to go to the chat, and I'm going to paste that in.

So now if you go to this bitly url.

So it's a bit.ly/biostats_stream.

And let me-- and Asly says, Andy is such a Hufflepuff with a heart emoji.

ANDY CHEN: Thank you.

COLTON OGDEN: So bit.ly-- let me make sure this is working--

/biostats_stream.

Yep, it works perfectly.

ANDY CHEN: Good.

And if anybody is curious, go to bit.ly if you want to have a really long url,

and you want to shorten it down, you can do that at bit.ly.

Bitly, as it's called.

COLTON OGDEN: Indeed.

OK.

ANDY CHEN: I think we have a few comments.

Nuwanda333, I am a Hufflepuff.

Thank you, I think.

I think it's a good thing, right?

COLTON OGDEN: I think so.

I think the Hufflepuffs are--

I actually don't know what the--

ANDY CHEN: I think they're the catch all.

COLTON OGDEN: I think they're the friendly--

like I actually honestly don't know too much about it.

ANDY CHEN: OK, well I'll take it.

COLTON OGDEN: All I know is that they're friendly.

ANDY CHEN: Sure.

And then in response to TwitchHelloWorld.

So I am doing my masters in bioinformatics.

COLTON OGDEN: And did you say you're doing with NCS?

ANDY CHEN: I'm a special student in the graduate school

of Arts and Sciences, which means I am sort of a visiting

student within the university.

COLTON OGDEN: Mm.

OK got it, got it.

Makes sense.

Only three megabytes, says faceless voice [INAUDIBLE] surprised.

The data set is roughly small.

ANDY CHEN: Yay.

It's just text.

COLTON OGDEN: No big data today.

This is small data.

Sort of.

ANDY CHEN: It's approximately 10,000 entries, if I recall.

COLTON OGDEN: That's actually pretty sizable.

ANDY CHEN: Actually I think it's exactly 10,000 entries.

COLTON OGDEN: Oh, wow.

Next we'll find the number.

ANDY CHEN: We'll find out.

COLTON OGDEN: Forces me to install a stupid Chrome add on.

ANDY CHEN: Oh, don't do that.

It's so-- actually let me see if I can show what it should look like.

Do not install the Chrome add on.

It's-- here.

So can we--

OK great.

So if you hit it once, and it should, da, da, da--

I don't know what's going on.

No, no, you don't want this.

Do not do this.

This is-- OK.

I think-- there we go.

So you want it actually--

COLTON OGDEN: I guess you got to click on it twice.

Just don't install the add on.

The upload is a little bit shady.

ANDY CHEN: It's a little--

I wouldn't trust it.

Those kiwis-- no, I'm just kidding.

COLTON OGDEN: Trying to get some ransomware on everyone's computer

today.

Make a little extra money on the side.

ANDY CHEN: That's actually what they pay me for.

It's my real job.

But all right, let's get back to R. The first link on r-project.org is

downloading the language itself.

All right, so what we're going to do is under the Getting Started section

we're going to go to Download R, this link right here.

We're going to click it.

And then, so these are--

COLTON OGDEN: We maybe we want to command plus a couple of times,

just so we can see a little bit.

It's a little small.

ANDY CHEN: Let me see if I can-- yeah.

Is that better?