Data Analysis 1: What is Data? - Computerphile
What is data? Dr Mike Pound begins to formalise this much used word. This is part 1 of the Data Analysis Learning Playlist: • Data Analysis with Dr ...
This Learning Playlist was designed by Dr Mercedes Torres-Torres & Dr Michael Pound of the University of Nottingham Computer Science Department. Find out more about Computer Science at Nottingham here: bit.ly/2IqwtNg
This series was made possible by sponsorship from by Google.
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This video was filmed and edited by Sean Riley.
Computer Science at the University of Nottingham: bit.ly/nottscomputer
Computerphile is a sister project to Brady Haran's Numberphile. More at www.bradyharan.com
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Check out the full Data Analysis Learning Playlist: kzread.info/head/PLzH6n4zXuckpfMu_4Ff8E7Z1behQks5ba
Please make a video where Mike is just going aroud the campus pointing on things, persons and asking the camera whether this is data ;)
HAAHHAHAHA THAT EDITING OF THE RACE IS AMAZING I LOVE THIS CHANNEL
@JesusisAlive_33
5 жыл бұрын
thats one part of this channel i really admire
@MrFeupinha
5 жыл бұрын
Freaking love Mike and Computerphile.
4:56 "Degrees kelvin" *several physicists are typing*
@raining1975
5 жыл бұрын
returnexitsuccess , can’t you convert Celsius to kelvin and change it from interval to ratio?
@returnexitsuccess
5 жыл бұрын
@@raining1975 Yes you can, my comment was referring to the fact that Kelvin is not a "degree" scale, it is an absolute scale.
@nahco3994
5 жыл бұрын
@@returnexitsuccess Isn't it the same with his pH example? The pH scale is logarithmic, not linear, and it measures the concentration of hydrogen ions. So I got the feeling that it wasn't really the best example for what he was trying to say.
@harrysvensson2610
5 жыл бұрын
@@returnexitsuccess I am so furious with you because you taught me that Kelvin is not referred to with degrees. I hate this. I want to write 3° K. But because of you I won't. I'll write 3 K instead. Thanks a lot for ruining my day.
@misterhat5823
5 жыл бұрын
Don't forget the Rankin scale.
Shout out to Sean for saying "01" instead of "1" so that it sorts properly with episode "10".
That race animation was just pure gold! And as always - dr Mike Pound is great. Keep up the awesome work!
Computerphile doing what the best stats books couldn't do in a 10-minute video! Thanks a whole ton Mike! This is priceless for me!
You promised to use
@flurki
4 жыл бұрын
I think he said he was going to try to, that's not a promise :P
When the four data types were enumerated, we should say that the third, the interval data, allow for two main operations: 1.differences (or delta): 30 degrees minus 20 degrees = 10 degrees is a meaningful calculation; 2. Ratios of such differences. E.g. (50-30)/(30-20)=2 is meaningful in the way that it takes twice caloric energy to change a body’s temperature from 30 to 50 degrees than to change it from 20 to 30
he's so upbeat it's hard to believe he's in academia
@MrCmon113
5 жыл бұрын
Fortunately I swallowed my drink before reading that comment.
@userou-ig1ze
5 жыл бұрын
@@MrCmon113 but why? Too much gritty disillusionment?
@MrFeupinha
5 жыл бұрын
I love how much passuion he has, Mike is my favorite!
@ethank5681
4 жыл бұрын
Toxic academics are the worst
@userou-ig1ze
4 жыл бұрын
@@ethank5681 They're the new 'normal'
love the Netflix aproach of releasing the whole season at once
@stephens4490
5 жыл бұрын
I know what to binge on tonight!
4 kids is double of 2 kids, that's too many kids. That killed me.
I can imagine him going around campus asking about random objects: "is this data?" "What's wrong with Dr. Pound?" - Nothing, he's just like that
Mike. You are phenomenal. You explain like you understand, as you do. Clear and precise.
Now I kinda want to know avarage hex value of people's favorite colors
@AnujShahshahmanuj
5 жыл бұрын
Or just the average wavelength/frequency
As a data analyst, a lot of people get really caught up in r and python. They are great tools for sure, but, if you have access to a database then nothing beats good old fashioned sql for sorting, cleansing and transforming and quick analysis.
@HenrikDalsager
5 жыл бұрын
Except sql and big data may be difficult to combine if there is more data than SQL is designed for, in those cases where your data Is stored in something like hadoop, you may not be able to produce a schema that allows you to utilize SQL.
@steamyjungleman
5 жыл бұрын
@@HenrikDalsager fair point, my point is that no all data analysis involves such massive data sets and when discussing data analysis for new people sql should be mentioned also.
@SwiftUIByExample
Жыл бұрын
MapReduce != SQL
its great to know that an 11 min video taught me more about statistics than my stats module did... cleared up a lot of confusion they left me with xD
This is excellent, thanks Dr Mike Pound and Computerphile! Really looking forward to drilling into this.
What is Data? Our cat is Data. Lieutenant Commander Data is his full name. Thanks for this series on Data Analysis!
4:47 I think we CAN tell if a pH is double another one. A pH of 7 is exactly 10 times higher than a pH of 6 (i.e. the molar concentration of a hidrogen solution is 10 times higher).
@Lightn0x
5 жыл бұрын
Also.. about degrees Celsius, sure you can't dirrectly say that 100 is 2 times hotter than 50, but if you convert them to kelvin, you get 373 and 323, so indirrectly you can say that 100 degrees Celsius is 15% hotter than 50 right?
@Lefaseer
5 жыл бұрын
@@Lightn0x This is what I was wondering too. If you can convert an interval feature to a ratio feature so trivially then what's the point?
Nice series. Hope to see more like this on many topics.
Well Thankyou doctor.. I don't understand at all when my teacher explain. But now I understand.. THANKS A LOT
Thank you for the great learning series. How can I get the csv files for this lesson and each lesson?
Is it possibly to analyze logarithmic data? Like decibels?
I'm a bit dissapointed that intro didn't continue for the whole "what is data?" video, with Mike holding up different things and asking "is this data?" for up to 12 minutes
@AbCd-kq3ky
5 жыл бұрын
People are gonna have a field day counting the 'data's in this playlist
If you make a course - I will probably sign up to that platform and go through it, because I love the channel and I love how people talk about things.
Isn't pH a ratio type but on a log scale. Yes, there is no "zero", but you can calculate what is double a pH value, or more easily what is ten times a given pH value.
@zachhugo7424
3 жыл бұрын
I came here to say the same thing. I think you're right
Are the datasets used in this series available for download if you want to follow along? I can't find a link in the description...
You need a Udemy course, Mate. You are an excellent teacher. You get into the minds of people.
Awesome channel
It seems like the line between a nominal attribute and an ordinal one is a little blurry. I'd argue that you can order weather types by how conducive they are to outdoor activity (e.g., sunny > overcast > rainy).
Isn't all interval data also ratio? For example if you subtract the left most value in the interval representation to get the zero? Or is the problem here that you don't always know the left most variable, since you only know a sample that represents the underlying truth. I was just confused since he said that degrees Celsius is interval data, while it can be easily translated to Kelvin that is ratio data.
The beginning of this video is very good out of context
why cant we calculate the mean of Ordinal data? But we can for Interval? why does mean temperature make sense but mean star rating not?
"Is This Data?" shouldve been an absurd comedy skit on the Eric Andre Show or something
can we get the course files, so that we can follow along?
Proudly supported by thinkpad :D
Is NOIR considered an exhaustive list?
I realize you used temperature merely as an example of the interval data set type, but this particular measurement can be converted to a ratio data type (by converting C or F to K). Would there be any rational (pun intended) reason to do this?
Data analysis in Excel is generally not done because it has lots of quirks once you go deeply into the formula's, Microsoft has included a lot of bugs for the sole purpose of being backwards compatible. Things like dates and references introduce mistakes that are often hard to spot.
Are examples like this standardised or something? In my uni Databases course I made a decision tree for whether or not tennis would be played based on information like weather...
@harrysvensson2610
5 жыл бұрын
I don't think it's standardized, it's more like use the most basic algorithm that solves the problem for you and call it a day. In your case a decision tree solved your problem, and you called it a day.
This is two videos. Up to 5:24 you just can that and have it as a separate video. It's weird having been in computing and never having had it explained this way to me before. They didn't even teach this on my computer science degree. Before I say this video data to me was just anything in a format that enables it to be processed by machine. Because of that though, I'm suspicious: Does data really always fall neatly into one of these categories? Colours, for example, seem to fall into more than one: Yes, you can have nominal red, green, blue, cyan, magenta, yellow, white, but you can also have them stored as RGB values, or a HSV/HSB values. You can have it represented on a CIE graph, and you can have it as radiation frequencies. In the real world, does data really always fall neatly into one of the jars?
Can I use primary and secondry data together
This is good.
Thanks. Bro
If you have a kind of interval data like pH, you can't say that pH 10 is twice as much as pH 5, ok. But pH is a kind of data that can be converted to ratio data (since pH = -log([H+])). So, in a sense, since you can't convert easily with a formula, pH itself might not be rational, but you could rationalize it with just a couple more steps.
Does ratio data necessarily have a linear scale? That is, is 2 necessarily half of 4? Some measures are expressed as a logarithm, such as the Richter scale, but having a zero that means there's none, so in this case Richter 6 is 10X Richter 5. Of course a logarithm can always be expanded to a unitary value, so my question is more about practicality.
9:02: Do R dataframes start at 1? 😨
@ganondorf5573
5 жыл бұрын
Your name is absolutely relevant.
Data is a Lieutenant Commander on the USS Enterprise-D
well you can't have less than -273.15 degrees celsius so wouldn't that make it ratio if kelvin is?
You are awesome
NOIR data types (nomrinal ordinal interval, and ratio):
0°C + 273.15 = 273.15K ?
Finally
won't negative wind mean no atmosphere?
Is this data? No... This is... SPARTAAAA
Data is a character in Star Treck
Omg... Sean Riley has the same name as my Data Anonymous sponsor.
Everytime I open a video in this channel, I got trapped in it.!! 😍
I was really hoping he would hold a picture of Brent Spiner in the beginning
Massive missed opportunity was not holding a pic of Commander Data... “is this data??”
I don't understand why can't Celsius be considered ratio if there is a 0 C ? Why would it be wrong to say 20 C is twice as hot as 10 C?
@TheMacfruit
5 жыл бұрын
Ruilin Lin because that would imply you can say how much hotter 10° is compared to -10°. The math works out to -1, but that doesn't make any sense.
3:00
Pretty sure I asked this same question during Star Trek: First Contact.
He should've held up a picture of Data from Star Trek at the beginning. Is this data?
2:30 I think Safiya Nygaard would beg to differ 😂
isn't the ph table a ratio
The example of pH isn't a good one. There is a mathematical difference between each number in the scale.
@Hexanitrobenzene
5 жыл бұрын
I rewinded video and I think it's correctly placed in "interval data" category. It can't be used for ratios directly, though. If you divide pH 1 by pH 0, you get infinity - nonsensical answer. In order to get meaningful ratio, you must convert it to concentration of H+, then you get 0.1. However, you are now working with DIFFERENT numbers, which are now on ratio scale - their zero is "true".
@kevinolson9940
4 жыл бұрын
Hexanitrobenzene that argument doesn’t hold. I could just as easily say if you divide 1 child by 0 children you an undefined result. That doesn’t mean it isn’t type of ratio data. The rational numbers themselves are ratios of integers and they also break if you try and have a ratio of anything over 0.
3:01 "The Rimmer experience"
Oh look, Mike Pou- CLICK
I don't know why, but every time i see Dr. Pound i just want him to have the best life possible. So charismatic.
Question is Am i data?
@harrysvensson2610
5 жыл бұрын
Are we data? :o
@argeon87
4 жыл бұрын
We are all data biologically speaking. Some sources prompt somewhere around 150 Zettabytes (10^21) of data. And I guess it's mostly nominal one))
7:38 Lenovo Thinkpad X1 Extreme winks
What are data?
I love g-easy teaching
I see Dr. Pound, I click faster than *data*
I'd also discern discrete and continuous data (for the lack of a better word). Discrete data: can take only certain values like Yes, No, Maybe ( 😁 ), integers. It makes no sense to calculate an arithmetic mean, aka average. Frequency counting is OK. A median is also appropriate. A typical misuse of actually discrete data is when they publish that the typical family has 2.3 children. WHAT? This includes nominal, ordinal, and interval data. Continuous data: I'd put the the data you mentioned as "ratio" in this group.
godsend
Right?
negative wind is just wind in the opposite direction
Im happy because? that peter parker have the same Portatil like my portatil thinkpad t470
5:22 Why can you do t-test with Ratio data and not Interval data? I am sure it is possible to do a t-test with temperature data
@gustavnilsson6597
5 жыл бұрын
I guess with temprature you can just convert it to kelvin and back?
8:00 even the pros can't avoid those r syntax errors : )
What is data is a question. How do you collect your data is another question.
ones and zeroes! There! I just saved you 12 minutes.
Mike, Red > Blue.
You actually can determine what "double the pH" of something is, since pH is actually just the negative base ten logarithm of the concentration of hydronium ions. Edit: tl;dr it's ogarithmic, so double the pH is equal to pH*log2
Problem with a series on big data, drop all the vids at once and the algorithm hides them all.
Huh ? But the wavelength are.. oww.. ok :'(
So what IS data?
excited to see 54 year old John running down the wing
The mean temperature is 0K ? What? ;)
Ratio data... 100 kelvin is 2 times higher than 50 kelvin... OK. How many times is 100 kelvin higher than 0 kelvin, or how many times is 200 kelvin higher than 0 kelvin.
What *ARE* Data! Data is plural. Datum is singular.
tsk tsk Dr Pound didn't know that pH is a logarithmic scale.
@userou-ig1ze
5 жыл бұрын
I'm sure he does? What minute?
@Hexanitrobenzene
5 жыл бұрын
I think the point is that you can't use pH for ratio directly, you must convert it to concentration of H+ ions. The same for degrees Celsius - there is a well known relationship between Celsius and Kelvin scales, however, degrees Celsius can't be used for ratios because their zero is "not true".
@userou-ig1ze
5 жыл бұрын
@@Hexanitrobenzene You're confusing this with Fahrenheit
@Hexanitrobenzene
5 жыл бұрын
@@userou-ig1ze How so ? 0 degrees Celsius is 273,15 degrees Kelvin, the molecules still have a fair amount of thermal energy.
its not what is data, its who is data ;)
WHAT IS DATA
I am data.
Its just me or get the feeling that he thinks Python is nos free... made me double check after many years using it
@jony6828
5 жыл бұрын
ikr
Did Toni Kroos become a computer scientist?