Data Quality and Understanding Data

Data Quality

Data is everywhere, zettabytes (10^21 bytes) of it. But is the data good data?
Most of the time it is not. And bad data comes with big consequences. Today we will learn about data quality. and understand when the data is good data when the data is bad data.

Data Quality
Image Source: Pixabay

Data Quality and Issues:

Data must maintain some qualities to be good data. If one or more of them are missing then It is bad data. But it’s always not possible to get good data. Understanding the data thoroughly is very important in working with data. If bad data goes unnoticed then it must bring no good. Let’s see the qualities of data.


It is not possible to always get complete data. Sometimes you have to drop rows with missing values or sometimes just let it be. But either way you must understand if there is a pattern. Here is why

Image source: Riskwerk

“The most important data is the data you don’t have” – Abraham Wald


Is the information both correct and precise? Without accurate data whole data analysis is wrong and this will lead to wrong decisions. So the source and the process of data collection must be reliable. And after collecting the data must be verified and examined.


DateActivitySpent time

Something wrong in the table above. We humans can easily understand it when it is a small data set. But when the data set is overwhelmingly big or we directly feed it to the machine there will be a faulty model. So there must be a process of checking the uniformity.


Repetition of data will lead the analysis to wrong conclusion because the model will be over-fitted to some samples. You need to understand the columns to remove the duplicate rows.



When the data was collected and when the data is valid for. Is your information up to date? Imagine you use a database say for a student council election campaigning only to find that most of the contacts of that database are a couple of years old.

There’s a saying that Data scientists spend 80% of their time preparing data.
This stage is very important for good quality data.

36 thoughts on “Data Quality and Understanding Data”

  1. Yesterday, while I was at work, my sister stole my apple ipad and tested to see if it can survive a thirty foot drop, just
    so she can be a youtube sensation. My iPad is now destroyed and she has
    83 views. I know this is completely off topic but I had to share it with someone!

  2. There are many ways to begin finding your true self, info is as simple as connecting
    with ourselves physically through self-massage. But since the volume increases,
    there will also be low-cost knockoffs available.
    Research has established that nurturing touch boosts the launch
    of oxytocin, a hormone that creates feeling of nurturing and sensation of

  3. I like the helpful information you provide in your articles.
    I’ll bookmark your blog and check again here frequently.
    I am quite sure I will learn a lot of new stuff right here!
    Best of luck for the next!

  4. Just want to say your article is as surprising. The clarity to your
    put up is just nice and i could suppose you’re knowledgeable in this subject.
    Fine with your permission let me to snatch your RSS feed to keep up
    to date with forthcoming post. Thanks a million and please continue the enjoyable work.

  5. I don’t know if it’s just me or if perhaps everyone else experiencing issues with
    your website. It seems like some of the written text in your posts are running off the screen. Can someone else please provide feedback and let me know if this is happening
    to them as well? This might be a problem with my browser because
    I’ve had this happen previously. Thanks

  6. I know this if off topic but I’m looking into starting my own blog and
    was curious what all is needed to get set up? I’m assuming having a blog like yours would cost
    a pretty penny? I’m not very web savvy so I’m not 100% positive.
    Any recommendations or advice would be greatly appreciated.

  7. I’m amazed, I have to admit. Seldom do I encounter a blog that’s
    both educative and amusing, and without a doubt, you’ve hit the nail on the head.
    The issue is an issue that not enough men and women are speaking intelligently about.
    I am very happy I found this in my hunt for something relating to this.

  8. Hi there are using WordPress for your site platform?
    I’m new to the blog world but I’m trying to get started and create my own. Do you require any coding expertise to make your own blog?
    Any help would be greatly appreciated! asmr 0mniartist

  9. I’m gone to convey my little brother, that he should also visit
    this weblog on regular basis to get updated from newest news.
    0mniartist asmr

  10. Link exchange is nothing else except it is just placing the other person’s
    web site link on your page at proper place and other person will also do same in favor of

  11. Thank you for the auspicious writeup. It actually used
    to be a enjoyment account it. Glance complicated to far delivered agreeable
    from you! However, how can we keep up a correspondence?

  12. It is really a nice and helpful piece of info. I’m satisfied that you just shared this useful
    information with us. Please keep us up to date like this.
    Thank you for sharing.

  13. Hi to all, how is the whole thing, I think every one is getting more from this site, and your views are fastidious in favor of new visitors.

  14. scoliosis
    We’re a group of volunteers and starting a new scheme in our community.
    Your site provided us with valuable info to work on. You’ve done an impressive job and our whole community will be thankful to you.

  15. I believe this is one of the so much important info for me.
    And i’m satisfied reading your article. But want to
    commentary on some general issues, The website taste is perfect, the
    articles is in reality nice : D. Excellent job, cheers

  16. Hi! I know this is kinda off topic however , I’d figured I’d ask.

    Would you be interested in exchanging links or maybe guest authoring a blog post or vice-versa?
    My site addresses a lot of the same topics as
    yours and I feel we could greatly benefit from each other.
    If you are interested feel free to send me an e-mail.
    I look forward to hearing from you! Excellent blog by the

  17. Someone essentially help to make significantly articles I would state.
    This is the very first time I frequented your website page and up to now?
    I amazed with the research you made to make this particular
    post extraordinary. Great process!

  18. Wow that was unusual. I just wrote an extremely long comment but after I
    clicked submit my comment didn’t appear. Grrrr… well I’m
    not writing all that over again. Regardless, just
    wanted to say excellent blog!

  19. Normally I don’t learn post on blogs, but I would like to say that this write-up very pressured me to check out and do it!

    Your writing style has been amazed me. Thank
    you, quite great article.

  20. I’m not that much of a online reader to be honest but your blogs really nice, keep it up!

    I’ll go ahead and bookmark your site to come back later.

    Many thanks

Leave a Comment

Your email address will not be published.