270 likes | 275 Views
Discover how machine learning can revolutionize the hiring process by streamlining resume ranking and improving accuracy. Presented by Vinayak Joglekar, Co-Founder and CTO of Synerzip.
E N D
Lean Hiring Aided by Machine Learning Presented by Vinayak Joglekar, Co-Founder and CTO, Synerzip December 18, 2014
Discussion Topics • The Problem • Lean Hiring • Resume Ranking - Choice of Algorithm • Data Acquisition and Cleaning Challenges • Initial Results • Improving Accuracy • The Road Ahead Confidential
Needle in the Haystack Situation Waste in the process of hiring = resumes reviewed but not selected + candidates interviewed but not selected. Every candidate “hypes” the resume to a certain extent. Much time is wasted reading pages of hyperbole to discover the grain of truth. Hiring managers have other priorities - their precious time is wasted in interviewing unsuitable candidates whose resumes look good. Confidential Confidential
More Choice Isn’t Always Better Is this all you have? Some more please Send Some more Can I see some more resumes? Week 3 Week 2 Week 1 Feedback after 4 weeks Myth: More choice = better selection Reality: More choice = waste + delay + confusion Confidential
Make Them Jump through Hoops Common response to the problem is to have a strict filtration process consisting of series of tests and interviews. Good candidates are often not actively looking for a change. They get turned off by the long evaluation process. The evaluation process is often flawed with too much stress on specific skills than abilities. Tests are susceptible to gaming. Confidential Confidential
Discussion Topics • The Problem • Lean Hiring • Resume Ranking- Choice of Algorithm • Data Acquisition and Cleaning Challenges • Initial Results • Improving Accuracy • The Road Ahead Confidential
Kanban Confidential Extensively used in automobile industry. Principle: Any process consisting of a workflow can’t run faster than the bottleneck. All sub-processes that run faster than the bottleneck produce waste. Kanban ensures all sub-processes march to the drum-beat set by the bottleneck. Kanban is pull-based. A sub-process can’t pull more work than a pre-set WIP limit.
Solution: Lets Limit the Choice! Confidential
Challenge: Ranking Resumes It took half a day for an experienced recruiter to rank a few resumes. He kept asking what was more important: Was it pay, soft skills or experience? The answer is that it depends on the job. Each job needs a different weightage to be assigned to each one of these attributes. Thus ranking reduces to assigning appropriate weightages to the attributes. Confidential
Discussion Topics • The Problem • Lean Hiring • Resume Ranking- Choice of Algorithm • Data Acquisition and Cleaning Challenges • Initial Results • Improving Accuracy • The Road Ahead Confidential
Why Logistic Regression? • Training a machine learning algorithm for resume ranking would require a significant number of resumes that are pre-ranked by a human expert. • It is very difficult for human expert to rank resumes. • On the other hand we have a lot of resumes that are classified as suitable or unsuitable which can be used to train the logistic regression algorithm. The graph here shows how the probability of a resume being suitable depends on the attributes (X) and the weights assigned to them (θ) hθ(X)=1/(1+e-Z)where Z= θ1X1+ θ2X2 +…+ θnXnwhere X1,X2,..,Xn are various attributes and θ1,θ2,..,θn are the weights assigned to them Confidential
What is Decision Boundary? • x1 = experience and x2 = pay • 1 = suitable and 0 = unsuitable • Observation 1: More pay reduces the probability of selection and more experience increases the same • Decision boundary is an imaginary line that separates suitable & unsuitable examples • In this case the line is x1-x2-3=0 • Points below the line are likely to be suitable • Points above the line are likely to be unsuitable • Points along the line have equal probability of being suitable or unsuitable – hence hθ(X)=.5 & θTX=0 along this line Confidential
Training, Test & Validation Sets Over/ under fitting? Validation Set (20%) Supervised Learning Algorithm Validation Testing Input Valid } Training 60% Training Set(60%) Test Set (20%) } Validation 20% } Test 20% Available Data Output Testing is the measure the accuracy with which true positives and true negatives are predicted by the algorithm. In tests like cancer detection; false negatives can prove to be fatal. Confidential
Implementation Challenges • Very difficult to manually rank/ grade resumes thus we can’t use standard ranking algorithms. • Small training sets, even smaller test sets. • There are more than 13 attributes - experience, education, pay, location, availability, stability, current job, etc. based on which a candidate is selected or rejected. Many of these attributes are subjective and need to be quantified. • There is no clear decision boundary. Gross Compensation 1 Decision Boundary 0 1 0 0 1 0 0 1 0 0 0 0 1 0 1 0 1 1 0 0 0 1 0 0 1 1 1 0 1 0 Relevant experience • We addressed these challenges by using data from our ATS about 20 job openings for which more than 3000 resumes were considered and more than 400 candidates were found suitable to be called for interview. • We used a sixth degree polynomial that lends itself well to render a decision boundary with an irregular shape. • We quantified the subjective attributes like education, stability etc. • We used every 4th record to test and others to train the algorithm. Confidential
Discussion Topics • The Problem • Lean Hiring • Resume Ranking- Choice of Algorithm • Data Acquisition and Cleaning Challenges • Initial Results • Improving Accuracy • The Road Ahead Confidential
Results and Analysis • When we used the values of weightages delivered by the algorithm to predict, we could correctly predict 89% of the examples in the training set that was used to train the algorithm. • The same algorithm could predict 65% of the test examples. • We improved the accuracy by 9% when we used the sixth degree polynomial. • We used the weightages to assign ranks and the ranking was well accepted and appreciated by hiring managers within Synerzip. • We started practicing Kanban and lean hiring as ranking enabled us to put WIP limit on the number of resumes entering the hiring process. • The hiring efficiency improved and we were able to fill in more positions without adding any new recruiters. Confidential
Example Weightages - Analysis It turns out to be a fairly distributed set of values for weightages for various attributes. Each job opening uses independent assessment of resumes. This position assigns positive weightage to total experience but negative weightage to relevant experience. The requirement was for a broader skillset beyond just C++. This job opening gives extremely negative weightage to “current compensation” – this means that candidates earning well are not suitable; while its just the opposite case for most other job openings. Confidential
Comparing Results Confidential
Discussion Topics • The Problem • Lean Hiring • Resume Ranking- Choice of Algorithm • Data Acquisition and Cleaning Challenges • Initial Results • Improving Accuracy • The Road Ahead Confidential
Improving Accuracy • We tried using regularization to avoid over-fitting. However it did not yield any improvement in accuracy. As we have the accuracy at 89% while predicting the training set itself, it can be intuitively concluded that over-fitting doesn’t need to be addressed. • We need to get more training data to improve accuracy. Also the training data should pertain to a period over which the job requirements are constant. It’s very hard to find job openings where more than a hundred candidates are screened. As we plan to implement lean hiring and Kanban, the chances of having large training sets is very low. • We tried seeing if principal component analysis can be used to reduce the number of attributes to 2 or 3 to be able to plot. We could not get the “retained variance” anywhere close to 99%. (In fact, it was close to 50%.) Confidential
Discussion Topics • The Problem • Lean Hiring • Resume Ranking- Choice of Algorithm • Data Acquisition and Cleaning Challenges • Initial Results • Improving Accuracy • The Road Ahead Confidential
Future Roadmap • Create search engine app with ranking on the fly to limit the number of search results that fit within the smartphone screen with no need to scroll. • Try using sixth degree polynomial with more attributes. Currently we are using it only on expected compensation and relevant experience. This will most likely improve the accuracy. • Using NLP for information extraction and more precise attribute values. Confidential
www.synerzip.com Hemant Elhence hemant@synerzip.com 469.374.0500 • 23 84 Confidential
Synerzip in a Nutshell Confidential • Software product development partner for small/mid-sized technology companies • Exclusive focus on small/mid-sized technology companies, typically venture-backed companies in growth phase • By definition, all Synerzip work is the IP of its respective clients • Deep experience in full SDLC – design, dev, QA/testing, deployment • Dedicated team of high caliber software professionals for each client • Seamlessly extends client’s local team, offering full transparency • Stable teams with very low turn-over • NOT just “staff augmentation”, but provide full mgmt support • Actually reduces risk of development/delivery • Experienced team - uses appropriate level of engineering discipline • Practices Agile development – responsive, yet disciplined • Reduces cost – dual-shore team, 50% cost advantage • Offers long term flexibility – allows (facilitates) taking offshore team captive – aka “BOT” option
Our Clients Confidential
Next Webinar Agile Leadership: Want to change your results?Change how you lead. Complimentary Webinar: Wednesday, January 21, 2015 @ noon CST Presented by: Niel Nickolaisen, Chief Technology Officer at OC Tanner. He also co-authored “Stand Back and Deliver: Accelerating Business Agility”which gives you the agile leadership tools you’ll need to achieve breakthrough levels of performance. Confidential
Thanks! Call Us for a Free Consultation! Hemant Elhence hemant@synerzip.com 469.374.0500 facebook.com/Synerzip @Synerzip_Agile linkedin.com/company/synerzip Confidential