The field of data science continues to grow, allowing businesses to be driven by data with better insight and knowledge. Whether you are a professional who works in the field of data sciences or students, see this data science blog that is often updated and with the highest number of followers. Never miss developments in data science interview and also the data science interview questions which are as follows :
Q1. Explain what regularization and why it’s useful.
Resision is the process of adding parameters of tuning to the model to induce subtlety to prevent overfitting. This is most often done by adding a constant double to the existing weight vector. This constant is often L1 (LASSO) or L2 (Ridge), but in reality it can be any norm. The model prediction will then minimize the average loss function calculated on the driving training set.
Q2. What data scientists do you admire the most? Which startup?
This question does not have the correct answer, but here is my personal list of 12 data scientists who I admire most, not in a certain order.
Geoff Hinton, Yann Leecun, and Yoshua Bengio – to survive with the mesh neural when and start the current in-depth learning revolution.
Demis Hassabis, because of his extraordinary work in deepmind, which achieved human performance or superhuman in the Atari game and recently left.
Jake Porway from Datakind and Rayid Ghani from U. Chicago / DSSG, to allow scientific contributions to data for social goodness.
Patil DJ, the head of the first US US scientist, because it uses data science to make our government work better.
Kirk D. Borne for his influence and leadership on social media.
Claudia Perlich for brilliant work on the advertising ecosystem and functions as a great KDD-2014 seat.
Hilary Mason for a great job at Bitly and inspired others as a big star rock star.
Usama Fayyad, to show leadership and set high goals for KDD and data science, which help inspire me and thousands of others to do their best.
Hadley Wickham, for his fantastic work on data science and data visualization in R, including DLPLYR, GGPLOT2, and RSTIUDIO.
There are too many startups that are very good in the field of data science, but I will not include it here to avoid conflicts of interest.
Q3. How you validate the model you created to produce a predictive model of quantitative outcome variables using multiple regression.
If the value predicted by the model is far outside the range of the response variable, this will immediately show a bad estimate or inaccuracy of the model.
If values seem reasonable, check parameters; One of the following will show bad estimates or multi-collinearity: signs of opposing expectations, great or small and small values are extraordinary, or observed inconsistency when the model is given new data.
Use the model for predictions by feeding new data, and using the coefficient of determination (r squared) as a measure of model validity.
Use data separation to form separate datasets to estimate model parameters, and others to validate predictions.
Use Jackknife Resampling if the dataset contains a small number of examples, and measures validity with r squared and average error squared (MSE).
Q4. Explain precision and remember what it is. How do they relate to the ROC curve?
Calculating precision and withdrawals is actually quite easy. Imagine there are 100 positive cases between 10,000 cases. You want to predict which ones are positive, and you choose 200 to have a better chance to capture a lot of 100 positive cases. You recording your prediction ID, and when you get the actual results, you summarize how many times you are right or wrong. There are four ways to be true or wrong:
TN / Really negative: negative and predictable negative cases
TP / right positive: positive and predicted positive cases
FN / False negative: positive case but predictable negative
FP / FALSE positive: negative case but predicted positive
Q5. How can you prove that one improvement that you bring to the algorithm is really an increase not to do anything?
Often observed that in pursuing rapid innovation (aka “Fame Quick”), the principles of scientific methodology violated lead to misleading innovation, eg. Interesting insight confirmed without strict validation. One of these scenarios is a case that remembers the task of increasing algorithms to produce better results, you might come up with some ideas with the potential improvement.
A clear human impulse is to announce these ideas as soon as possible and ask for its implementation. When prompted to support data, results are often limitedly divided, which is very likely to be influenced by the selection bias (known or unknown) or a minimally misleading global (due to lack of varieties in test data).
Data scientists did not allow human emotions to master their logical reasons. While the right approach to prove that one repair that you bring to the algorithm is truly an increase that does not do anything will depend on the actual case, there are several general guidelines:
Make sure there is no selection bias in the test data used for performance comparisons
Make sure the test data has enough variations to become a symbol of real life data (help avoid overfitting)
Ensure that the principles of “controlled experiments” are followed by i.e. While comparing performance, test environment (hardware, etc.) must be exactly the same when running the original algorithm and new algorithm
Make sure the results can be repeated with the same results
Check whether the results reflect Maxima / Local Minima or Maxima / Global Minima
