Wednesday, September 29, 2010

Choking (continued)

One of my US readers pointed me to a Wall Street Journal book review (here) "What Happens Under Pressure: Two books investigate the not-so-fine art of choking." Greg Norman's choke in the 1966 Masters (from comfortable lead to a five stroke loss) is nominated for Choke-of-the-Century. The two books reviewed, Clutch by Paul Sullivan and Choke by Sian Beilock come to conclusions that are similar to Johnah Leher in How We Decide (reviewed in a prior post).

There are a few new insights: (1) The younger you learn your skills, the less you are likely to over-think the situation and choke, (2) People who are basically analytical (anal retentives) have a tendency to over-think and choke, and (3) arrogance ("Pride goeth before the fall").

The recommendations to prevent a choke (at least for sports): (1) distract yourself so you don't over-think the mechanics, (2) keep a steady rhythm, (3) change your technique every so often to avoid going stale, (4) know your abilities (sometimes choking is just not being good enough--more practice, more discipline) and (5) put yourself into competitive situations to learn how to handle the stress.

Sunday, September 26, 2010

Choking, Swing Analysis and Swing Thoughts

Jonah Lehrer in a fascinating book titled How We Decide (recommended to me by one of my South African readers) asks us, on page 136 to "Consider one of the most famous chokes in sports history: the collapse of Jean Van de Velde on the last hole of the 1999 British Open". Lehrer argues that choking is the result of the rational brain taking over and creating doubt just at the point we should be relying on trained muscle memory.

If choking is the inevitable result of rational swing analysis, how do we go from analyzing our swings (rational mind) to actually playing golf (automatic muscle memory)? I suspect this isn't as easy as forgetting about our swing analysis when we're under pressure. Choking is an issue at the end of almost every professional golf tournament and today was no exception watching Jim Furyk win both the Tour Championship and the Fed-Ex Cup, the later for a $10 million bonus!

Furyk didn't play that well in the last few holes but got the win with a great bunker shot and solid short put. His thought process on the 17th hole was interesting. He didn't hit a great drive although it was in the middle of the fairway. He had over 200 yards left to the green and was afraid of hitting a jumper (it was raining) with his utility club. He explained in an interview that if he hit over the green he could loose the tournament. The shot he did hit was fat but ended up in the fairway short of the green (a safe miss) from where he bogeyed to be leading the tournament by only one stroke. He had to par the 18th and he did.

Whether or not Furyk choked a little or not, his "rational" play was very different from Van de Velde's play on the 18th hole at Carnoustie. Van de Velde made some miserable decisions after a poor drive that only put him in more trouble and saw his three shot lead evaporate while playing down the 18th hole. All he had to do was play safe, get a bogey or even double bogey to win.

Jonah Lehrer thinks that Van de Velde was "...suddenly focusing on the mechanics of his stroke, making sure that he didn't torque his wrist or open his hips." I'm not sure what he was thinking about but, at the time, it seemed to me that he just wasn't thinking.

Maybe it's fair to say that Van de Velde's swing wasn't solid enough to go on auto pilot when he needed it. It's probably also fair to say that swing analysis is not enough to produce a solid swing that won't crack under pressure. I recall Curtis Strange commenting that when under pressure he had only one swing thought: "Complete the backswing." After all the analysis and experience playing under pressure, it probably boils down to finding that one swing thought!

Friday, September 24, 2010

Stack & Tilt: My Backswing

Continuing the GolfTEC analysis of my swing, here is the start of the backswing with Ernie Els on the left, me in the middle and Stack & Tilt (S&T) on the right. Starting the backswing, what GolfTEC is looking for is weight shift and a stable lower body. The weight shift results from the upper body turning behind the ball. Notice the lines against Ernie Els' back leg and head. The right leg stays within the line but Ernie's head has moved back from the original position. The lower body can rotate to get a full shoulder turn but without swaying (moving the right leg backwards). Contrary to S&T, GolfTEC wants the head to move backward in the backswing and move back a lot (12 inches in my case).

My swing was described as a "reverse pivot" with the weight moving forward to the left foot and my head moving substantially forward of the ball. I could not find an exact S&T model for this point in the swing but if you roll the frame on the right back a bit in your mind, it looks pretty much like what I am doing. About the only thing that GolfTEC liked about this position was that my arms and hands have good extension and good wrist hinge.

From my perspective, I didn't realize that my head was moving that far forward. I thought I was keeping my head steady. Now that I see it on the video, I don't like the way the swing is starting.

P.S. Today I played a round of golf going back to my old width swing with possibly some elements of the Hogan-missing-piece swing. I didn't score that well (it was a cold day with swirling winds) but I hit some nice shots letting my weight shift back on my right foot. My playing partners commented that my swing looked more fluid. It seemed a little easier to play but I had to continually concentrate on taking a full shoulder turn and making sure my hips cleared on the downswing (at least I had only one swing thought through the round). And, as you'll see later, I wasn't getting a full shoulder turn with S&T.


Thursday, September 23, 2010

Stack & Tilt: My Setup

In a prior post, I showed video clips of my current S&T swing compared to the one suggested by a GolfTEC PGA pro during a swing evaluation session (you should see a number of other GolfTEC videos when you look at either of my videos, here or here--very interesting). Now I'll get into the details starting with the setup.

Considering just the top three frames (starting in frame 1, it's me, Tiger and Stack & Tilt). GolfTEC wanted me : (1) in a more athletic posture (I was standing taller to avoid fat shots), (2) standing further away to get more space between hands and body, and (3) with more bend from waist (like Tiger). About all that's good about my current setup is the knee flex. Notice that the S&T setup (frame 3, top) is halfway between me and Tiger.

On the bottom three frames (Ernie Els, me and S&T), GolfTEC wanted: (1) the ball played a little more forward in the stance (I'm hitting a seven iron here), (2) feet less flared (this was, from the LAWs of Golf Width swing, designed to get more turn), (3) good forward shaft lean, (4) upper body and head behind the golf ball (the diagonal green arrow is there to suggest moving the body and head behind the ball). Compared to the S&T setup (frame 3 on the bottom), my weight is not as far on my left side as they would suggest (that never felt comfortable to me). Compare the head positions in the bottom three frames: Ernie is behind the ball, I am right over the ball and S&T is actually ahead of the ball.

I like the more athletic setup. Interestingly, I can't do S&T from that setup! What I can do is V. J. Trolio's "Hogan's Missing Piece" swing (more about that later). The green numbers on the middle frame, bottom show that my setup is on the OK but marginal side (the number backgrounds would be yellow or red for poor positions--you'll see more of those later).

Wednesday, September 22, 2010

Stack & Tilt: My Swing

Yesterday I went to GolfTEC and had a complementary swing analysis. One of the GolfTEC PGA pros took me through their G-swing system: (1) putting me into an electronic harness (from the front, it looks like the strap for a backpack in frame 2 above), (2) video recording and digitizing my swing, (3) analyzing my swing against Ernie Els and Tiger Woods, (4) making some initial suggestions for improvement and (5) suggesting a number of lesson packages. Here is the video of my current swing (the S&T Swing) vs. the suggested new swing (the Width Swing). What's funny about this is that the "new" swing was basically my old swing before I went to Stack & Tilt (S&T)!

Whether I go back to the future or not is an open question, but the video analysis did point out some obvious flaws in my S&T swing. The flaws are clearly covered in the S&T video, but somehow I wasn't able to translate what I knew into a solid golf swing. The S&T book suggests video recording of your swing but I doubt that I would have caught all the problems without an objective analysis. GolfTEC is clearly adding value.

Maybe you can find the problems in my swing by comparing the S&T Swing to the Width Swing. In the next few posts I'll take you through the GolfTEC analysis with some of my own commentary. There were a number of interesting and, for me unexpected, conclusions from the analysis.


Tuesday, September 14, 2010

Stent vs. Bypass: The Gold Standard Study?


The New England Journal of Medicine recently published the results of the SYNTAX trial (here), a multi-center, multi-country randomized clinical trial comparing percutaneous coronary intervention (PCI) with drug-eluting stents vs. coronary-artery bypass grafting (CABG). The study seems to suggest that more patients should be undergoing CABG since there was more revascularization in the PCI group (death rates at 12 months were the same, although stroke in the CABG group was higher). Let's take a closer look using the causal model of heart attacks discussed in an earlier post (here).

Consider first the problems of designing a true randomized clinical trial comparing a procedure (PCI) with an invasive surgery (CABG). You simply cannot randomly assign patients to either treatment condition. Many patients would prefer to avoid a seriously invasive procedure such as CABG and a few more patients would prefer to avoid any procedure at all. And, that's exactly what happened. From the hierarchy diagram above (click on the diagram to see an enlarged view) 1262 patients were found ineligible, the majority because they had a treatment preference (probably PCI). Another 1275 were eligible only to be placed in a parallel, nested registry where 1077 enrolled in CABG and 198 enrolled in PCI. In other words 2537 patients were not randomized compared to 1800 that were randomized.

As a practical matter, self-selection cannot be avoided. As a consequence, study results really are only applicable to people that meet criteria (three-vessel or left main coronary artery disease) and had no treatment preference. It would be nice to know the rates of revascularization, mortality and stroke in the groups that were not randomized.

The study has a number of other limitations reported by the authors but no mention is made of the 12-month histories of cardiac rehabilitation in any of the groups. If there was no cardiac rehabilitation (e.g., substantially increased aerobic exercise), the rate of revascularization might be explained by that alone. If, for example, all 1800 patients were sedentary in the first 12 months, CABG may produce better outcomes. What cardiac rehabilitation, weight control or smoking cessation programs the PCI group went on (if any) is unclear. The issue isn't discussed in either the paper or the supplementary material, although my guess is that the standards of cardiac rehabilitation are very different in the countries that participated in the study.

On the basis of this study (and the other existing clinical trials reviewed in the paper), should treatment protocols change?

Monday, September 13, 2010

Russia is Burning



Shown above is a prediction for the year 2065 from the NOAA/GFDL CM2.1 Climate Model. Most of the World's land masses are predicted to be well above average temperatures for 1971-2000. What might be the consequences of global temperature change at this level?

Consider what is happening right now in Russia: This year, Russia recorded the hottest day (100 degrees) since record-keeping began in 1880. Wild fires continue to burn out of control. Smoke from the fires has substantially increased air pollution in Moscow. Russia's state environmental agency concluded in 2008 that Russia was warming twice as fast as the rest of the world. As a result of the heat and drought, Russia has banned the export of wheat while US wheat exports are booming.

Here's the causal model:


Positive signs on arrows are implied while two negative signs in a row (drought reducing the Russian wheat harvest which is negatively related to the US wheat harvest) are read as a positive impact (as discussed last week in Global Change). For good measure, throw in the floods in Pakistan (more energy in the atmosphere generating stronger monsoons).

Right now, the environment (especially climate change) seems to no longer be an issue in Washington yet, Russia is burning. In 2065, the NOAA model predictions for the US are not reassuring, but that's 55 years from now and elections are in less than two months.

The Russian ban on wheat exports is also creating the potential for a world-wide food crisis. The NY Times, in an editorial, asks that Russia learn from the last food crisis caused in part by demand for biofuels (another environmental issue) and not pursue "misguided polices". Imagine the rationality of policy making if world temperature increases by a few more degrees by 2065.

Friday, September 10, 2010

The Stimulus and Globalization

A recent editorial in the NY Times from the US Business and Industry Council argued that the government expenditure contained in the US economic stimulus package leaked away as consumers purchased imports from foreign countries. The council's suggestions: (1) buy American and (2) impose Tariffs. Each of these policy interventions can be analyzed using the causal model presented in an earlier post. Part of the causal model is displayed above (click on the graphic to see a larger image).

Government expenditure with a "Buy American" requirement would stimulate domestic sales, increase production, create jobs and create more demand (some of which would go to imports). Tariffs (taxes) on imports would make them more expensive and reduce demand.

Beggar-my-neighbor trade policies have been tried before. The Smoot-Hawley Tariff didn't work during the Great Depression and may have made things worse. But, the Business and Industry Council argues that tariffs worked during the Nixon Administration when, in 1971, Nixon imposed tariffs on Japan, Germany and other countries that refused to let their currencies rise. The tariffs were part of the Nixon Economic Shock (to include wage and price controls) in response to inflation generated by the Vietnam War.

Neoclassical economists argue that tariffs are a bad idea because they raise the price of domestic goods and damage the world economy. We would need a causal model of the world economy to discuss the later point (maybe in a future post). However, the effect of tariffs depends on what is being taxed. If we impose tariffs on countries with substandard environmental controls (green- or eco-tariffs), we benefit our own economy and benefit world environmental systems.

What do you think are the chances that the US Congress would impose tariffs? How about the chances that the US Congress would impose eco-tariffs?

Wednesday, September 8, 2010

The President's New Plan


It's getting close to the mid-term elections in the US and President Obama has a new plan for business tax breaks. Robert Reich gave a great commentary on NPR's Market Place and the commentary seemed to be based (with some embellishment) on the causal model above (click on the graphic for an enlarged view).

The president is proposing corporate tax cuts for R&D. Tax cuts will lead to the development of labor-saving technology that reduces jobs. Profits might also generate some investment (if there is demand). Otherwise, profits will be expended on CEO pay and Shareholder dividends which fuel the Stock Market casino (didn't that all start the Great Recession in the first place, that is, too much easy money sloshing around).

The problem we're having right now is inadequate demand created by the Great Recession (you can see the vicious circle in the graph: lack of demand leads to lack of sales leads to lack of production which leads to unemployment which decreases demand, etc.). Interest rates could be lowered by the Federal Reserve but they are almost at zero (the zero-bound) right now. Exports could be increased but the rest of the world is also in recession. Imports could be reduced (e.g., automobiles) but that requires demand for US products.

What remains is the Keynesian economic prescription: government spending. There is only one problem with increased government spending: it is being blocked by deficit hawks, fiscal conservatives, sound money evangelists, and bond vigilantes. The same dynamic played out during the Great Depression until WWII intervened.

So, the President's New Plan will be counterproductive (R&D tax cuts could decrease jobs), the Fed is at the zero-bound, and government expenditure will not increase unless we have another World War. What's going to happen?

Eventually, the markets will have their way and, in the words of Andrew Mellon (Herbert Hoover's Treasury Secretary), the markets will:

...liquidate labor, liquidate stocks, liquidate farmers, liquidate real estate… it will purge the rottenness out of the system. High costs of living and high living will come down. People will work harder, live a more moral life. Values will be adjusted, and enterprising people will pick up from less competent people.

For people that believe in markets and for people that do not, Mellon makes an important point. All markets will eventually adjust to bubbles created in other markets (e.g., housing and the stock market). The adjustments are brutal and painful if not necessarily swift. Subdivided ghost towns will be bulldozed or left to decay, jobs will be shipped to low-wage countries, companies will fail, people will drop out of the work force or take jobs below their skill level, and eventually there will be a new equilibrium.

The politics of all this are a little infantile: The US father figure (the president) is expected to fix the mess yet, at the same time that he is expected get out of the economy by reducing expenditure and regulation. I just heard another great Catch-22 in NPR Marketplace tonight: all the stimulus funds have not been spent because there are not enough federal workers to manage the contracts.

A Better Model of Heart Attacks

In a previous post, I presented a causal model of heart attacks and commented that the model could be improved. Pictured above is an improvement that specifically includes coronary artery blockage. Compare it to the excellent discussion and animation available from the National Institute of Health. The way to read this causal diagram is to look at the input variables and trace their effects through the system (as you are tracing a single path through the diagram, the effects are positive until you encounter a negative sign):

(1) Genetics (family history) and life style (overweight, smoking, diabetes, etc.) can lead to coronary blockage.

(2) Intervention in the form of a diagnosis can lead to either prevention, drug treatment or angioplasty and stents, all of which can reduce blockage and reduce the chance of heart attack.

(3) Heart attacks, however, can also be caused directly by shocks (e.g., taking cocaine, emotional stress or pain, exposure to extreme cold, cigarette smoking, etc.) or heart spasms (tightening of a coronary artery that cuts off blood flow through the artery--the causes of coronary artery spasm are not well understood).

The causal diagram above seems to capture the current understanding of heart attacks but it doesn't explain why you or a sample from the general population will have a heart attack and it doesn't predict which interventions will reduce the chances of having a heart attack. This is because there are too many back-door paths that can create a heart attack.

You could (1) have a heart spasm, (2) continue smoking, (3) drop out of your cardiac rehab program, (4) gain weight, (5) become diabetic, (6) become a drug addict, (7) stop taking your prescription medications, etc. etc. Out of all this, the only thing you can't change are your genetics or family history and the stents you may or may not already have in one or more coronary arteries. If angioplasty and stents don't prevent future heart attacks, as some research suggests, it does not mean the angioplasty is an unnecessary or ineffective treatment. There are simply too many back-door paths to that future heart attack to draw that conclusion.

Tuesday, September 7, 2010

Doctors, Patients and Causality

Boston.com reported on a study that found a "yawning disconnect between what doctors say and what patients hear." The study, in the Annals of Internal Medicine (here), asked 153 patients who had received angioplasties whether the patients thought that the procedure could prevent death or heart attach. The same question was posed to 27 cardiologists. The patients thought stents would reduce the chances of heart attack while the cardiologists didn't. The study interpreted the finding as the result of misunderstanding in communication (something similar to problems reported for husband-wife communication).

From a theoretical perspective, there are a number of problems with that conclusion. The cardiologists, patients and the researchers are confusing counterfactual, causal, interventional and probability statements. The counterfactual question for patients that had a heart attack: "If you didn't have angioplasty, would you have had a heart attack?" The causal question: "What causes heart attacks?" And, the intervention question: "What diagnoses and treatments might prevent a heart attack?"

The differences in questions can be seen from the causal diagram above. There are lots of "causes" for heart attacks (the "back-door criterion) in addition to coronary blockage (genetics, life style, some kind of event or "shock," etc.). As a result of a heart attack or a diagnosis, either drugs or stents or both are used to treat the blockage. Would a patient with coronary blockage and chest pain and troponin elevation (meaning they had a heart attack) have had the heart attack with an earlier diagnosis and angioplasty? Probably not. But other blockages, not alleviated by stents, can develop over time and other causes, unrelated to blockage, can cause heart attacks.

Maybe too many people are receiving angioplasty when they have stable angina. Maybe drug treatment or prevention treatment or life-style changes would reduce the angina. But, if someone has 95% blockage in an artery, it's probably time for a stent. Essentially, the study poses a trick question for both patients and cardiologists by only asking about the stent -> heart attack link. Although patients and doctors may not communicate clearly, if patients and doctors were oriented to a better causal map (the one above could be improved), they'd probably reach the same conclusions.

PS: There are lots of other problems with the study: (1) small sample size, (2) lack of randomization, (3) single-site bias (all patients were treated at the Baystate Medical center), etc.


Monday, September 6, 2010

Stack & Tilt: When The Wheels Fall off


We've all, I'm sure, had a round where the wheels just seem to fall off. I had that kind of round this Saturday. Admittedly, it was windy, cold and my body just did not seem to be cooperating. On the back nine, out of desperation, I just went back to basics and concentrated on keeping my weight on my left side. It was my only swing thought and it helped pull the round back together.

Today, I decided to just carry that one swing thought to the course no matter what happened. Here was the outcome: (1) no problems with the wind, (2) no fat shots, (3) length off the tee comparable if not better and more accurate than usual, and (4) best score of the season. Maybe Zach Johnson is on to something!

I did have one problem with my irons. Using this swing, the face kept closing (divots point to the right of the pin and the ball flying left of the pin--on a few of the divots I could see that the face was closing down at impact).

I didn't really get the problem under control on the course but I was reminded of comments in the Smash It 3/4 Swing (push "...the palm of the right hand toward the target through impact to prevent the clubface from snapping shut") and Step 5 of the Six Steps to S&T (arms straight, second frame on the right above). Peter Kostis feels that Zach Johnson compensates for the shut clubface with a very strong body rotation.

The shut clubface problem will need more practice and on-course time for me. I will try all these various solutions in addition to opening the clubface a little more on the backswing. But, as is mentioned in the S&T video, if you do nothing else prescribed in the S&T swing, keeping your weight on your left side is the most important key to solid ball contact. When commenting about his solid ball contact in windy conditions at the British Open, Tom Watson said "It's the weight." A cryptic comment, but I think he meant keeping his weight on his left side. I'd love to ask him that question (actually, Tom seems to think control on windy days is a result of grip pressure--worth a try).