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Ways Data Projects Fail

martingoodson.com

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Re: Ways Data Projects Fail

#2
Good to see that data cleaning was #1 on that list. Whenever I do work on a side project, it takes way way more time to get and structure the data than it does running the algorithms. Granted, that's because I have to go out and get the data in the first place, and then make sure it's useable and in the correct format.

Like the recent project I'm doing trying to classify country music songs based on their topic on the data blog I write on (https://bigishdata.com), the amount of time it's taking to scrape lyrics, remove duplicate / incorrect songs, and then do manual classification for training data is taking far longer than running the ml algorithms in the end one I've gone through that process.

I've been looking for jobs recently, and I've seen only one job posting that mentions data cleaning as a necessity, whereas the rest only talk about data science and algorithm knowledge, or overall ETL design on the data engineering side. Seems like data set knowledge should be emphasized more.

Re: Ways Data Projects Fail

#3

Good to see that data cleaning was #1 on that list. Whenever I do work on a side project, it takes way way more time to get and structure the data than it does running the algorithms. Granted, that's because I have to go out and get the data in the first place, and then make sure it's useable and in the correct format. Like the recent project I'm doing trying to classify country music songs based on their topic on th…

Yes! Came here to write this too. I've been spending the last few years thinking, inquiring and talking about this, and I think there definitely is a field emerging here. There are already some companies trying to think about this stuff, and classes give it lip service but I don't think we've even seen the tip of the iceberg.

It's interesting to talk to different people about data quality and what they think it means, or how they choose to deal with it, and it's all over the place. Some people just mean open and consistent formats, some people have stylistic preferences for data shape, some people talk about accuracy of values, etc etc.

In some ways it's an extension of the thought that the world is inherently noisy, and we've been thinking about that one already, it's just that it turns out you don't need sensor data a la robotics to get noisy data - it's already in the datasets we know and love, and you accumulate more of it, the more sources you pull into your analysis.

Re: Ways Data Projects Fail

#4

Good to see that data cleaning was #1 on that list. Whenever I do work on a side project, it takes way way more time to get and structure the data than it does running the algorithms. Granted, that's because I have to go out and get the data in the first place, and then make sure it's useable and in the correct format. Like the recent project I'm doing trying to classify country music songs based on their topic on th…

I agree, and would add: data cleaning's importance to the quality of the result is also often underemphasized compared to the much bigger focus on the quality of the algorithms. A single bad decision on data cleaning can have a large effect on the end result (in many cases, more than choosing between algorithms, assuming you pick some vaguely reasonable algorithm). Especially any choice that ends up producing non-random effects, like deduplicating things in a way that ends up biased: it's common that missed duplicates in an automatic deduplication process aren't randomly distributed. Or a scraping process that ends up with biased samples. You can correct for these kinds of things in various ways (e.g. incorporating an estimate of the bias in a statistical model), but people who don't consider data cleaning a "real" part of the whole statistical modeling pipeline in the first place usually don't.

Re: Ways Data Projects Fail

#5
The big one that's missing: There is nothing you can conclude from your data. It's clean, it makes its way properly to the analyst, and yet, there's just nothing there...

Re: Ways Data Projects Fail

#6
post #5

The big one that's missing: There is nothing you can conclude from your data. It's clean, it makes its way properly to the analyst, and yet, there's just nothing there...

Hypothesis driven data science is over the head of too many people.

Re: Ways Data Projects Fail

#7

Good to see that data cleaning was #1 on that list. Whenever I do work on a side project, it takes way way more time to get and structure the data than it does running the algorithms. Granted, that's because I have to go out and get the data in the first place, and then make sure it's useable and in the correct format. Like the recent project I'm doing trying to classify country music songs based on their topic on th…

Any specific resources you'd recommend on data cleaning, verification, etcetera? I've just started reading this: https://www.amazon.com/Accuracy-Economic-Observations-Oskar-... . I've seen a few other books on the subject which I'm planning to get into, but I'd be interested if anyone has specific recommendations.

Re: Ways Data Projects Fail

#8

Good to see that data cleaning was #1 on that list. Whenever I do work on a side project, it takes way way more time to get and structure the data than it does running the algorithms. Granted, that's because I have to go out and get the data in the first place, and then make sure it's useable and in the correct format. Like the recent project I'm doing trying to classify country music songs based on their topic on th…

Yes! Came here to write this too. I've been spending the last few years thinking, inquiring and talking about this, and I think there definitely is a field emerging here. There are already some companies trying to think about this stuff, and classes give it lip service but I don't think we've even seen the tip of the iceberg. It's interesting to talk to different people about data quality and what they think it means…

Data governance and master data management spring to mind as existing ideas along these lines.

Re: Ways Data Projects Fail

#9

Good to see that data cleaning was #1 on that list. Whenever I do work on a side project, it takes way way more time to get and structure the data than it does running the algorithms. Granted, that's because I have to go out and get the data in the first place, and then make sure it's useable and in the correct format. Like the recent project I'm doing trying to classify country music songs based on their topic on th…

Any specific resources you'd recommend on data cleaning, verification, etcetera? I've just started reading this: https://www.amazon.com/Accuracy-Economic-Observations-Oskar-... . I've seen a few other books on the subject which I'm planning to get into, but I'd be interested if anyone has specific recommendations.

Honestly, as another commenter pointed out, seems like an emerging field. Best practices and processes are just being figured out, and I haven't seen any great resources online talking about what to do, especially since most of what you need to do depends on the data set and how you're storing the data, and that can vary widely.

Like I recently dealt with finding duplicate song lyrics in my 5000 set of lyrics, and to do that, I just had to google around for StackOverflow answers or random blog posts before I found something that I could adopt and chance for what I had.

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