World Mental Health Day and Statistics

Today is World Mental Health Day. 

Recently, I stumbled upon an engaging visualization representing the increase in the 'deaths of despair' due to the pandemic. Here is a link for the same.

https://lifelines.periscopic.com/

Do use the arrow icons to get more information. For example, in one of the panels, you can play around the different levels of 'mental health care', 'employment status', and 'social connect' to see the effect of these variables on the number of deaths of despair.

In recent years, the overbearing use of social media has been cited as one of the leading causes of mental health issues. This is because so many of us, at one point or other, have felt jealous of someone else, looking at their lives on social media. But, as students of statistics, we must remember that the data on social media are the classic example of data 'missing not at random'. 

What is meant by that? 

We all have heard the problem of missing data in statistics and how it can affect our conclusions. There have been many developments in the field of probability and statistics about handling missing data. However, most of these focus on the data  'missing completely at random'. 

On the other hand, what we see missing on social media is not at all random. We see hundreds of stories of weddings, new cars, new jobs, new babies, family picnics, festivities and whatnot. But we rarely see things like breakups, divorces, job losses, prolonged illnesses, infertility struggles, piled up debts on these platforms, even though these could be happening to the same people. 

So, as statistics students, let us remember that the grass always looks greener on the other side because the data are missing not at random. 

and here is another example of 'data missing not at random', ironically, received thanks to the social media 😎 

अखेर त्यांनी लक्ष्मणरेषा ओलांडली…

गेल्या काही दिवसांपासून जी बातमी येऊ नये असं वाटत होतं, ती बातमी अखेर आली. आपल्या सर्वांच्या जिव्हाळ्याच्या ‘common man’ ला जन्म देणार्‍या आर. के. लक्ष्मण यांनी अखेर आपला निरोप घेतला.

लिहिता-वाचता येण्यापूर्वीच, म्हणजे स्वतःच्या आयुष्याच्या पहिल्या दशकापासूनच नियतकालिकांमधल्या रेखाचित्रांमध्ये गुंगून जाणार्‍या एका छोट्या मुलानं पुढं अनेक दशकं असंख्य भारतीयांना आपल्या रेखाचित्रांमध्ये गुंगवून ठेवलं. रेषांचं सामर्थ्य काय असतं हे दाखवून देऊन त्यांनी आपलं लक्ष्मण हे नाव जणू सार्थ ठरवलं. जे जे स्कूल ऑफ आर्ट मध्ये प्रवेश न मिळाल्यानं खचून न जाऊन त्यांनी आपली पेन्सिल खाली ठेवली नाही, हे आपलं सद्भाग्यच!

‘टाइम्स ऑफ इंडिया’ मधून आपल्याला भेटायला येणार्‍या या ‘common man’ नं तत्कालीन परिस्थितीवर मार्मिक टिप्पणी केलीच, पण त्याचबरोबर अनेकदा ही टिप्पणी कालातीत बनून गेली. उदाहरणादाखल हे रेखाचित्र,

त्यांचे ज्येष्ठ बंधू आर. के. नारायण यांच्या ‘मालगुडी डेज’ साठी त्यांनी काढलेली चित्रंदेखील तितकीच बोलकी होती. त्यांच्यामुळे आपल्याला मिळालेला आणखी एक दोस्त म्हणजे एशियन पेंट्सचा ‘गट्टू’. 

त्यांनी रेखाटलेलं प्रत्येक पात्र हे अगदी साधं आणि आपलंसं वाटतं. त्यामुळेच आज एका कलाकाराला मुकल्याचं दुःख आहेच, पण त्याचबरोबर आपल्या अगदी जवळचं कोणीतरी गेल्यासारखी पोकळी निर्माण झालीये. 

सफर संभाव्यतेच्या विश्वातील - ३

सफर संभाव्यतेच्या विश्वातील - २ 

१९२० सालच्या उन्हाळ्यातील एक निवांत दुपार. केम्ब्रिज विद्यापीठाच्या दिग्गज प्राध्यापकांपैकी काही मंडळी आपल्या कुटुंबातील सदस्यांबरोबर चहा पीत गप्पा मारत बसली होती. तितक्यात उपस्थितांपैकी एका बाईंनी कपात चहा आधी ओतला की दूध यानुसार चहाची चव बदलते असं मत व्यक्त केलं. जमलेली सारीच मंडळी विद्वान. त्यामुळे काहींनी एकूणात मिश्रण तेच असल्यानं क्रम बदलून काय फरक पडणार अशी टिप्पणी केली. अचानक एक किरकोळ अंगयष्टीचा तरूण पुढे आला. "दुधात चहा ओतला आणि चहात दूध ओतलं तर चवीत फरक पडतो की नाही हे प्रयोग करून तपासून पहायला हवे " असं त्यानं सुचवलं. सर्वप्रथम त्या बाईंना तयार चहाचा एक कप देऊन तो कोणत्या प्रकारे बनवला आहे हे ओळखण्यास सांगायचं असं ठरलं. प्रत्यक्षात दोन्ही प्रकारच्या चहाच्या चवींमध्ये काही फरक नसला, तरी अंदाजाने उत्तर सांगून ते बरोबर येण्याची शक्यता ५० टक्के आहे. त्यामुळे हा प्रयोग एकापेक्षा जास्त वेळा करायला हवा. शिवाय बनवणार्‍यानं समजा मिश्रण नीट ढवळलं नाही, तर त्याचा परिणामही चवीवर होऊ शकेल. त्यामुळे अशा परिस्थितीत सगळे कप अचूकपणे ओळखण्याची अपेक्षा करणं गैर ठरेल. हे कप कोणत्या क्रमानं दिले जात आहेत, यावरही चव ओळखणं / न ओळखणं अवलंबून असू शकेल. या सर्व शक्यतांचा विचार करून त्या तरूण शास्त्रज्ञानं किती कप, कोणत्या क्रमानं दिले पाहिजेत आणि खरंच जर चवीत फरक असेल, तर किमान किती कप अचूकपणे ओळखता आले पाहिजेत याचं गणित मांडलं. हा तरूण शास्त्रज्ञ म्हणजेच आधुनिक संख्याशास्त्राचे जनक म्हणून ओळखले जाणारे सर रोनाल्ड फिशर. यातूनच पुढे फिशर यांनी “Design of Experiments (DoE) & Analysis of Variance (ANOVA)” या संकल्पनांचा विकास घडवून आणला.

आज बहुतेक सर्व क्षेत्रात DoE & ANOVA या संख्याशास्त्रातील तंत्रांचा मोठ्या प्रमाणावर वापर होतो. शेतात कोणत्या प्रकारचं खत, किती प्रमाणात वापरलं तर उत्पादनात वाढ होते हे ठरवायला याच तंत्राची मदत होते. अनेक शेतांमध्ये एकाच वेळी हा प्रयोग करायचा झाल्यास, प्रत्येक ठिकाणच्या मातीचे घटक वेगवेगळे असल्यामुळे खताच्या परिणामांमध्ये तफावत जाणवू शकते. ही तफावत दूर करून खताचा परिणाम अचूकरीत्या मोजणं, वेगवेगळ्या खतांची तुलना करून त्यांची गुणवत्तेनुसार क्रमवारी ठरवणं हे सगळं या तंत्राद्वारे शक्य होतं. जी गोष्ट झाडांबाबत घडते, तीच माणसांची. म्हणूनच, नवीन औषध बाजारात आणण्यापूर्वी करण्यात येणार्‍या चाचण्यांमध्येही हे तंत्र मोठ्या प्रमाणात वापरलं जातं. प्रत्येक रूग्णाची शारीरिक स्थिती वेगवेगळी असल्यामुळे औषधाचा परिणामही कमी-जास्त प्रमाणात दिसून येतो. त्यामुळे साधारण समान (वय, लिंग, वजन, आजाराची स्थिती इत्यादी) प्रकारच्या माणसांवरच एखाद्या औषधाची चाचणी केल्यास, ते औषध इतर प्रकारच्या व्यक्तींमध्ये प्रभावशाली ठरेल याची खात्री देता येत नाही. शिवाय नवीन येणारे औषध हानीकारक तर नाही ना (Side Effects) हे ठरवण्यासाठी देखील प्रायोगिक स्तरावर किमान किती लोकांना ते दिले पाहिजे, हे या तंत्राद्वारे ठरवलं जातं. दोन औषधांची तुलना करायची झाल्यास ती औषधे ज्या दोन गटांना दिली जातील, ते गट साधारणतः समान गुणधर्मांचे असायला हवेत. यामुळेच अलिकडच्या काळात, सौंदर्यप्रसाधनांच्या तुलनेसाठी, एकाच व्यक्तीच्या डाव्या हाताला एक आणि उजव्या हाताला दुसरं क्रीम लावूनही चाचण्या केल्या जातात. वेगवेगळ्या प्रकारच्या वेगवेगळ्या आकाराच्या समूहांवर केलेल्या या सगळ्या चाचण्यांमधील परिणामांची तुलना करून त्यावरून सार्वत्रिक निष्कर्ष काढण्याचं काम संख्याशास्त्रातील हे तंत्र करतं. अशा प्रकारे जिथे जिथे म्हणून विविधता आहे, तिथे तिथे हे तंत्र उपयोगी पडतं.

Back to Blog...

It has been really long, since I wrote...Dec-Jan is generally the most inspiring month for me (& probably for many young academicians like me) as it's a conference season. That's why, this blog also started in January, when I was overwhelmed by one such motivating experience. This year-end & New-year was no exception. It started with the alumni meet at our Department, where we actually got to meet many alumni about whom we had heard a lot; from our seniors as well as teachers. It was more like a family reunion for our ilk. Then came the conference to mark International Year of Statistics & Diamond Jubilee of our Department. Listening about Huzurbazar, Fisher and many more like them was really an interesting experience. 

Aurangabad Caves

After a while, we went for a conference at my Hometown. Visiting Aurangabad Caves, Panchakki after about 12-13 years was a refreshing experience. I had almost forgotten the beauty of these places. Getting to meet some old & new conference pals was as expected a nice experience. 

Then came a trip to Hyderabad, which was an unforgettable journey as we got to meet a living legend in Statistics, Prof. C. R. Rao. We got to talk to him and got a signed copy of his autobiography. This was really enthralling. The gallery at the C R Rao Institute was also worth visiting. We also got to meet some non-statisticians doing great work in Statistics. Getting to see the museums at Hyderabad was a pleasing by-product.

The latest in this series was a trip to Nashik for a national workshop. The journey to Nashik and the stay there were both amazing as I got to listen to many amusing anecdotes related to Statistics and Statisticians. It was really illuminating to see how even simple statistical tools can help us in real life.

Getting to meet so many great people has lengthened my wish-list. Let's see how many of them, I can  fulfill...


PS: Special thanks to Deep & Richa for their great company and lovely snaps...

On the Occasion of Statistics Day

Year 2013 is being celebrated as the ‘International Year of Statistics’. Since 2007, India started celebrating 29th June as the National Statistics Day. Most of us are scared of the numbers and the formulae that constitute the subject of Statistics. But, if used wisely these dreadful numbers and formulae can simplify the solutions of many real world problems. In fact, this has been proved many times even in the Indian context. At this juncture, I remember an incidence dating back to 1947. Our country was rejoicing at the newly acquired independence. However, at the same time, due to partition, some areas had a riotous situation. Red Fort in New Delhi was occupied completely by the refugees. Government had given the contract of providing food to these refugees to some contractor. But no one knew the actual count of refugees. As a result, the contractor took advantage of the situation and provided a huge bill. Due to explosive situation, it was almost impossible to enter the red fort and take the actual count of people. So, everyone was puzzled. At that time, a statistician named Dr. J. M. Sengupta came up with an interesting idea. Salt was the cheapest item among those foodstuffs. So, the contractor knew that he wouldn’t earn much by inflating the quantity of salt. Dr. Sengupta decided to use this knowledge. He estimated the average amount of salt consumed per head in the Indian families and used it to estimate the number of refugees inside the Red fort. This method was tested on another smaller colony of refugees and it was found to give accurate results. As a result, Statistics was useful in detecting the fraud.

The basic paper in Statistics “Ars Conjectandi” was written by Jacob Bernoulli, 300 years ago. This year also marks the 250th anniversary of the discovery of Bayes' theorem, which is useful in many fields. As a result around 124 countries and 2040 organizations all over the world have joined hands to celebrate this year as the International Year of Statistics. Special efforts are being made to increase the awareness about Statistics. The M.Sc. Statistics course in the University of Pune was started 60 years ago. So, to commemorate both these special occasions, Department of Statistics has planned various activities throughout the year and the concluding ceremony of these year-long celebrations will be held during an International conference and Alumni meet which would be organized in December 2013.

29th June is the birth anniversary of Dr. P. C. Mahalanobis, who is considered as the father of Statistical thinking in India. He played a major role in formation of policies regarding industrialization and economic planning in India. His work on sample surveys received a worldwide recognition. Indian Statistical Institute established in 1932, under his guidance has been continuously producing many statisticians who went on to achieve name and fame in the various fields of Statistics. An important Statistician from Maharashtra is Dr. P. V. Sukhatme. His work on hunger, malnutrition is noteworthy.

One more statistician who became famous world-over is Dr. V. S. Huzurbazar. Department of Statistics in the University of Pune was founded by Dr. Huzurbazar. He did his Ph.D. from Cambridge University and returned to India. He devoted all his energies for the growth of this newly established department thereby proving his mettle as a good administrator as well. He was awarded the coveted Adams Prize by Cambridge University. His work was efficiently continued by two of his students, Dr. S. R. Adke and Dr. B. K. Kale. Dr. Adke made significant contributions to the field of Statistics, during his stints as researcher/faculty members across various institutions in India, Australia, USA etc. He took sincere efforts to put in good shape the journal of Indian Statistical Association. Even until today, the Indian Statistical Association functions from the Department of Statistics, University of Pune and the journal is also published from the same department. Work of Dr. Adke was recognized by the “Distinguished Statistician Award”, which he received from the Indian Society for Probability and Statistics. Dr. Kale also had an illustrious career. Along with the Department of Statistics, University of Pune, he also played a major role in the growth and development of Department of Statistics, at the University of Manitoba, Canada. His books have been included in the syllabus of various universities. One of his books has been translated in Japanese. Dr. Kale received “Dr. P. V. Sukhatme” award from the Ministry of Statistics and Programme Implementation, Government of India. The same award was bestowed upon another Puneite Dr. J. V. Deshpande in 2012. Through his publications, Dr. Deshpande has contributed tremendously to survival analysis, which forms a basis of many problems in Medical science.

Due to the contribution of such stalwarts, the Department of Statistics, of University of Pune grew rapidly. Currently it is recognized as the Centre for Advanced Studies in Statistics by University Grants Commission. Every year around 50 students are admitted for M.Sc. course. Along with the fundamentals of Mathematical Statistics, these students get to learn about applications of statistics in various fields including Finance, Insurance, Economics, Genetics, Medical Statistics etc. Some students join research programmes such as M.Phil. and Ph.D. Due to ever-growing need for trained Statisticians, these students get placed in different sectors such as insurance, finance, software, pharmaceutical industries, banks, colleges, universities, research institutes, Indian Statistical Services etc.

Statistics has tremendous applications in the variety of fields, such as weather forecasts, psephology, market research, finance, economics, insurance, epidemiology, genetics, medical science, clinical trials, quality control etc. Statistics is required for assessment of efficiency of drugs, assessment of severity of the side-effects of the drugs, determining the causes of diseases such as cancer, maintaining the quality of the products, comparative study of efficiency of fertilizers, ranking of sportspersons, designing new insurance policies, determining the rate of spread of epidemic and accordingly the intensity of the measures to control this spread etc.

One more important contribution of Statistics, in the Indian history can be found in the works of Florence Nightingale. Her work as a nurse is well-known. But, she was a good statistician as well; in fact she was the first female member of the Royal Statistical Society. Her skill of representing the data into graphs proved useful for creating awareness about the health problems of soldiers. In those days, the reports on such issues used to be highly technical and hence were rarely read and understood by the politicians. As a result, no policy changes could be made due to lack of awareness about the severity of the problem. Her important contribution to the field of statistics was the Nightingale Rose Plot. It’s a variant of the pie diagrams that we generally see in the newspapers. In the pie diagrams, radius of each sector is same and the angle of the sector is proportional to the contribution of the corresponding fields, whereas in the Nightingale Rose plots, the angles are same for all the sectors and the radii are proportional to the contributions of the respective fields. Due to the simultaneous efforts on the statistical and medical fronts, Nightingale was successful in reducing the mortality rates among Indian patients from 69 per 1000 to 18 per 1000.

This is just a glimpse into the uses of Statistics. If you are further interested, you may visit the link: www.statistics2013.org. It also features a small video made by SAS company, to showcase the role of statistics in our daily lives. Prof. A. P. Gore, former head Department of Statistics, University of Pune has also composed a song for Statistics. You can listen to this song at: http://bit.ly/YcufiJ .

Amazon Story - 2

In continuation with the previous post, here are the points, due to which I may hesitate while ordering from Amazon again:

1. Even if you order and pay for things, you may not get them. You will get a refund (this is what they claim, I'm still unsure about that), but then we don't shop to get refunds. We shop for things that we need. So, if I have an urgent need for something, I won't rely on Amzaon as they tell you that they have run out of stock after a long wait. 

2. If your things don't get delivered, you have to complain first. They won't bother at all to inform you that  there is some problem with the order. They will keep on boasting on their site that they are processing your stuff and will deliver the things by the expected delivery date, which may even be a past date.

3. If they cancel an order due to non-availability of stock, they will completely erase that thing from your order history as if to wipe out all the evidences of the crime that they have committed. 

4. Sometimes after shipping, no tracking is possible. If some seller sends the things by some local courier, then it is okay. But, in one case, even for a seller whose parcel came by FedEx, tracking information was not available.

As a statistician, I know that this is a very small sample to conclude something about the "Brand Amazon", but I can't stop comparing this experience with my long time relationship with Flipkart, an Indian company, which is still a nascent company (compared to Amazon and ironically started by two ex-amazonians). 

I think I'll prefer buying from Flipkart, even if I have to pay a bit more because (as per my experience until now)

1. If you pay for something, you get that thing. They don't cancel your orders on their whim.

2. Until now, there has been no problem related to any order.

3. Even if you cancel some orders or don't pay for an order, all these orders are visible in your order history, with the appropriate remarks (Cancelled / Payment not received etc.). This helps you, specially if you want to place that order again.

4. Tracking page is always updated. In fact, the day on which you are supposed to get the delivery, you are alerted by an SMS. As a result, you can ensure that you are around when the delivery boy turns up.

5. If you cancel an order, you can store the refund amount in you Flipkart Wallet and use it for further purchases. This is faster than bank refund. I was a bit worried when I first used the wallet, as the balance in the wallet was not sufficient for my next order. But their system is smart enough and it deducted only the remaining amount (Price - Wallet balance) from my card.

I hope Amazon people will learn some day that "What a customer needs is a correct reply and not just a quick reply based on false information".

PS: I think I need to create a special label for my grievances: First it was Nokia, then Google and now Amazon. ;)

Amazon Story - 1

Recently Deep posted a status update on FB, saying "Just like chocolates, shopping also lifts the mood, bhalehi hi fir wo books hi kyun na ho or online kyun na ho". That was the day when we had ordered 10 books in a single day; 2 of them from Flipkart and 8 from Amazon. We have been a loyal customers of Flipkart, since last two years but had never ordered from Amazon before. This time, Amazon was offering exciting discounts for many good books and that too with free shipping for some of them. This tempted both of us to go on a shopping spree, just like last year. Then started the anxious waiting period. There are two types of anxieties: Nervous and Exciting. Initially, we were anxious excited; eagerly awaiting for having a glimpse at our newly acquired possessions, checking the tracking pages every now and then in the hope of new updates. In about 10 days, we got six of the books from Amazon and two from Flipkart. However, two from amazon were still pending. As the days passed, we started becoming anxious nervous. There was no change in the statuses of the books. I think here onwards, it's better to jot down the events chronologically:

18th June: I got an email from one seller saying that their stock was accidentally damaged and they cannot fulfill the order. So, they asked me if they can cancel the order. From the email, it seemed that refund is not the only option. So, I asked whether it is possible to get a delivery after a few days or so, as I was ready to wait. But, the seller claimed that the it was not possible and cancellation was the only option. This was a bit disappointing as I had ordered that book to gift it to a friend of mine and I had been happy to have found just the right gift at the right price. Now, giving that perfect gift is no more possible as the prices of the other available editions of that book are beyond my reach.

This experience increased our nervous anxiety. In case of the other book, Amazon was still showing Status as "Not yet dispatched" and "Expected Delivery Dates: 14 - 17 June, 2013". We started wondering whether these guys have got time machine which will help them deliver the book in past. ;)

Then there were few more days of anxious awaiting.

25th June: It was already one week past the cancellation date. But nothing emerged - neither the refund for the cancelled book nor the second book which was yet to be dispatched. The status quo of the status was maintained. The expected delivery date was still 14 - 17 June, 2013. Finally, our patience threshold was crossed. We decided to inquire about the actual status. We wrote an email to the customer care section and got an unexpected reply: "I see that your credit card that you chose for this order was deactivated and we were not able to charge for this order and hence we couldn't deliver the package for the book. However, we've already charged for the other book in the order and hence we were able to deliver this book to you."

Now here are a few things:

- Firstly, I had paid using debit card and not the credit card.

- Secondly, within minutes after payment I had got a confirmation email from Amazon and a message regarding deduction from the bank, both for the entire amount. So, I didn't see any reasoning in the argument that they had received payment for one book and not for the other book (as both the books belonged to the same order).

- Thirdly, the card with which I paid the bill is still active.

Irritated by this rude shock, I wrote to the executive again and got more worried about the refund status of the originally cancelled book. I wrote to the seller of the cancelled book to get update about the refund status. The seller contacted Amazon and here came their reply: "I have reviewed the order and it has been cancelled and the buyer has not been charged so no refund is required." 

In my opinion, this was the height of irresponsible behaviour, specially when Amazon is claiming to build "Earth's Most Customer-Centric Company".

Then I called up customer care executive twice, to explain the entire matter and got the reply that "Refund was not processed, because the other book from the same order is yet to be dispatched". I was relieved to hear that they are admitting that the payment is made. However, had I got the correct reply in the first place, it would have saved a lot of emails, calls and subsequently time and energy of both the sides (we and Amazon). 

26th June: I started my day again with an email from Amazon saying that the order of second book has also been cancelled and you will get the entire refund for two books. We were again irritated as we had no intention of cancelling that book. We couldn't see the reason behind this and frantically called up customer care again, only to be greeted by third person. I wanted to continue with the person with whom I had spoken  earlier as he had understood my entire problem and had reacted pretty sensibly. But this new person was not ready to handover the phone. So, I had to repeat my entire story, which I think she couldn't fathom. So, finally what she did was to keep me on hold on the pretext of checking the details and handed over the phone to the person, who had addressed this issue the earlier day. Here also, had she listened to my request of talking to the specific person, it would have saved time and energy of both of us. Finally, I got to know that the seller has again run out of stock and so my order was cancelled. The book is still available on Amazon, but with the different seller and so, I will have to order it again. There is no option of transferring the money directly to the new seller, though all of them are on the Amazon platform.

In short, the thing was an entire mess. I am hoping to get refund soon. I don't know if I will ever have the courage to order from Amazon again, due to the points, which I'll enlist in my next post.