Wednesday, May 19, 2010

Two Quotes I Like

In the United States we like to believe we are a capitalist society based on individual responsibility. But we are what we do. Not what we say we are. Not what we wish to be. But what we do. And what we do is make it easy to gamble with other people's money -- particularly borrowed money -- by making sure that almost everybody who makes bad loans gets his money back anyway. The financial crisis of 2008 was a natural result of these perverse incentives.
--Russell Roberts in Gambling With Other People's Money: How Perverted Incentives Caused the Financial Crisis.

Libertarians and socialists are motivated by the same problem: corruption. Because corruption generally requires political pull, libertarians believe you battle corruption by limiting government. Socialists believe political pull is mitigated by a better government, which for some reason is always a larger government.
--Bailey Norwood

Videos of Good and Bad Teachers

Thursday, May 13, 2010

America's Sweet Tooth: by Kalyn Neal

America’s Sweet Tooth: Sugar, Obesity, and Government Policies

By Kalyn Neal

This paper was originally prepared to satisfy the thesis requirement of an Honors Degree at Oklahoma State University. Ms. Neal will graduate in May, 2010 with a degree in agribusiness. After graduation, Ms. Neal will begin graduate studies in the Department of Agricultural Economics at Oklahoma State University. Questions or comments can be emailed to: or

Obesity rates among American adults have been steadily rising for the last 40 years.1 The potential cause of this increased obesity could be blamed on a myriad of factors; among the most criticized factor is government policy. Through various trade and domestic policies the U.S. government has influenced the volume and type of farm production, thereby influencing what Americans consume. The type and amount of sugar in particular is susceptible to policy changes. If these policies encourage excessive consumption of sugar and/or particular forms of sugar that encourage obesity, recent U.S. health problems might be an unintended consequence of farm policy. Indeed, this is exactly what some critics claim2 —is the criticism warranted? The purpose of this study is to resolve and articulate the degree to which food policy contributes to rising obesity rates in the U.S.

Understanding the relationship between obesity and agricultural policy is important for a variety of reasons. Obesity is now considered to be an epidemic in the U.S., for which the cause is uncertain.3 Obesity may be a state of health many individuals prefer. If individuals prefer the foods and lifestyles which contribute to obesity, and that is the sole cause of obesity, governmental policy to combat obesity is perhaps not warranted. However, much of the obesity problem resides with children, for whom responsibility lies with the parents and the community. Moreover, the rapid increase in obesity rates suggests obesity is not the result of private choices alone. To the extent that obesity is a negative consequence of agricultural policy, changes in policy to curb this consequence are paramount.4 First, to better understand the relationship between sugar and obesity, it is prudent to understand the various types of sugar that are consumed.

Sugar and Agricultural Policy

Sugarcane, before it can be processed into refined sugar, must first be processed into raw sugar. This is accomplished by extracting juice from the stalk of the sugarcane. The juice must then be clarified, boiled, and crystallized. The end product is then further refined to produce the finished product of refined sugar. Americans most commonly encounter sugar in its granulated form that can be bought in bulk at supermarkets.5

High fructose corn syrup (HFCS) is a by-product of the wet-milling of corn. HFCS is made by first converting corn starch into a syrup that is almost entirely comprised of dextrose. Enzymes are then introduced into the syrup which yields 42 percent fructose syrup known as HFCS-42. HFCS-42 can then be filtered through an ion-exchange column yielding 90-percent HFCS syrup. By mixing these two syrups, HFCS-55 can also be produced. High fructose corn syrup is not available for purchase by consumers; consumption occurs by eating foods that have been sweetened with the syrup.6

Based on the wide ranges of opinions available on the subject, it is difficult to determine whether or not the consumption of sugar or high fructose corn syrup has a positive or negative effect on one’s health. It is known that the amount of sweetener consumed, whether sugar or high fructose corn syrup, has risen since by 19 percent since the 1970s. The amount of corn sweetener has increased by 400 percent to 79 pounds annually in 2003.7 In a study observing the effects of fructose and glucose on a diet it was found that the increased consumption of sugar-sweetened beverages, and by association HFCS, is associated with weight gain. When fructose is metabolized it does not stimulate the production of insulin or leptin in the same way that glucose or natural sugar does. Insulin and leptin are major endocrine signals to the central nervous system which regulate the long-term energy balance of the body. An extended diet high in energy from fructose could lead to increased caloric—note the emphasis on could. Gaining the definitive evidence necessary to support this hypothesis would be difficult because it would require the subject group to consume a highly controlled diet for at least one year. The number of variables which would have to be controlled for in this experiment makes it very cost prohibitive.8

In the U.S. today there are two major food policy programs that affect American sugar consumption. Corn producers have been receiving governmental subsidies for decades. Past policies tied the amount of subsidy to the amount of corn the farmer produced, and this led to an increase in total corn production, lowering corn prices and encouraging food processors to utilize corn syrup as their primary sweetener instead of sugar. Current policy regarding subsidies has decoupled many payments from corn production. This means the amount of subsidy a farmer receives is no longer dependent on the amount of corn they produce each year. Corn production is now largely determined by market prices rather than by government subsidies. However, if decoupled subsidy payments still allow some farmers, who would otherwise cease farming, to continue their operations, corn subsidies may still be encouraging corn production at a higher quantity that free-market prices would dictate.

These events are depicted in Figure 1, where farm subsidies increase the supply of corn sugar. At any price, the U.S. corn sugar market will produce a greater volume. Because corn and cane sugar are substitutes, the lower corn sugar price would dampen demand for cane sugar (which would have a second-order effect of decreasing the corn sugar price further). The net impact is more total sugar, with corn sugar possessing a larger market share than cane sugar. Studies have indeed shown that the cost of producing corn is less than the market price, suggesting the subsidies comprise the difference between cost and price, encouraging corn production beyond its free-market level. The increase in sugar production and the substitution of corn syrup for cane sugar is referred to in this paper as the farm-subsidy effect.

The amount and type of sugar consumed domestically is also influenced by the U.S. sugar program. Through the use of tariffs, U.S. food policy forces the price of cane sugar to be artificially high. This is depicted in Figure 2, where the price of cane sugar rises when the tariff shifts the supply curve leftward. Through higher cane sugar prices, the tariff increases the price of corn sugar. The tariff thus leads to an increase in the price of all sugars – cane and corn syrup – which then discourages sugar consumption and thereby reducing the level of obesity. This effect is referred to as the cane-sugar-tariff-effect. Another effect of the tariffs, however, is to induce a substitution of corn sugar for cane sugar, and if sweeteners made from corn syrup have a larger impact on obesity than cane sugar, the tariffs could induce an increase in obesity.

The reader will note that the two linkages between agricultural policy and sugar consumption do not point unambiguously towards greater sugar consumption and subsequent obesity. The farm-subsidy effect certainly subsidizes sugar consumption, but the cane-sugar-tariff effect [essentially] taxes sugar consumption. Further, although both policies increase the percentage of sugar consumption comprised of corn sugar, there is no definitive study deeming corn sugar as an inferior sugar source. Thus, the critic who bemoans the supposed fact that U.S. policy encourages obesity is either privy to information this study is not, is making personal judgments about the relative magnitude of the farm-subsidy and cane-sugar-tariff effects, or acquires poor information. Of course, all policy recommendations require judgments of some sort. Rarely does science paint social issues as black-and-white.

Current food policy in the U.S. may be either contributing or helping to prevent rising obesity. The issue ultimately rests on whether or not the policies that encourage weight gain – farm subsidies and government-induced favoritism for corn sugar over cane sugar–overcome the policies that reduce weight gain. The soft drink industry serves as a fine example. Beginning in the 1970s, soft-drink manufacturers began to replace cane sugar with high fructose corn syrup.9 If corn syrup proves to have a greater effect on obesity than cane sugar, the change would make each ounce of soda consumed less healthy. Then, if agricultural policies make sodas cheaper than normal supply and demand conditions would suggest, increases in the ounces of sodas consumed would exacerbate obesity further. The relationship between U.S. food policy and obesity is fraught with ambiguity.


Recent increases in the rate of obesity among adults and children are commonly thought of as a problem, without giving careful consideration as to whether a problem actually exists. Surely, government does not view its role as targeting as specific weight for each individual. The weight of any individual is largely determined by the amount of food they choose to consume, the type of food they choose to consume, and the amount of exercise they choose to undertake. It may be the case that individuals view the price of food items, the opportunity cost of exercise, and make a deliberate decision to gain enough weight that they will be deemed obese by health professionals. The optimal weight is not the weight that maximizes health, but the weight the individual decides is best for themselves, given the price of food and exercise.

The government, and critics of certain governmental policies, are concerned that this personal weight decision is inappropriately influenced by subsidies that lower both the true cost of food and the true cost of producing cane sugar relative to corn sugar. If the government made vast amounts of food available for free to the public, and the public became grossly obese, this would surely constitute a problem warranting an adjustment of agricultural policy. There is something disturbing about the notion of subsidizing food to the point that obesity is referred to as endemic. Exploring whether this notion is reality thus seems a worthy endeavor.

In one sense, the issue is difficult because it seems impossible to untangle the effects of various policies in a manner that provides a clear answer as to the impact of food policy on obesity. In another sense, the issue is spectacularly simple when one asks: Why even have the subsidies in the first place? Agricultural economist Dan Sumner has asserted that the only valid reason we have agricultural subsidies is because we have always had them.10 Other agricultural economists contend that the sole purpose of farm subsidies is to redistribute wealth from the taxpayers at large to farmers and landowner.11 Farm subsidies do not seem a very worthy program. Even if farm subsidies have no effect on obesity, the fact that they are a tool for wealth redistribution suggests they should be abolished. The fact that these subsidies could very well encourage obesity simply provides further justification for abolishing farm subsidies, when no further justification from society’s perspective is even warranted.

Works Cited

[1] The Economics of Obesity: A Report on the Workshop Held at USDA’s Economic Research Service by Tomas Philipson, Carolanne Dai, and Lorens Helmchen, The University of Chicago, and Jayachandran N. Variyam, Economic Research Service

2 Farm subsidies and obesity in the United States: National evidence and international comparisons by Julain M. Alston, Daniel A. Sumner, and Stephen A. Vosti

3 Supra note 1

4 The Price is Right: Economics and the Rise in Obesity by Jayachandran N. Variyam

5 Sugar: Background for 1995 Farm Legislation by Ron Lord

6 Sugar and Sweeteners: Background by Stephen Haley, Economic Research Service

7 Going With the Grain: Consumers Responding to New Dietary Guidelines by Hodan Farah and Jean Buzby

8 Endocrine and metabolic effects of consuming beverages sweetened with fructose, glucose, sucrose, or high fructose corn syrup by Kimber L Stanhope and Peter J Havel

9 Going With the Grain: Consumers Responding to New Dietary Guidelines by Hodan Farah and Jean Buzby

10 Agricultural Subsidies: Corporate Welfare for Farmers by Dan Sumner

11 Supra note2

Appendix: Notes From Literature Review

The literature reviewed for this article fell into two categories, articles relating to food policy and those relating to diets and obesity. For the purposes of this review, these two categories are dealt with separately.

Diets and Obesity

“I welcome this chance to talk with you about a health crisis affecting every State, every city, every community, and every school across our great Nation. The crisis is obesity. It’s the fastest growing cause of death in America.” This is a quote made in 2003 by the former Surgeon General Richard Carmona and is one of the opening lines of the article, “The Price is Right: Economics and the Rise in Obesity[1]”. This article along with another, “The Economics of Obesity: A Report on the Workshop Held at USDA’s Economic Research Service[1]” seeks to explore the effect of the obesity boom on the American economy. Both testify to the fact that the obesity crisis did not just appear overnight but rather obesity rates have been steadily rising since this 1970’s and thus how we find ourselves facing a crisis today. The cause for the rise is currently unknown and is likely caused by a multitude of factors rather than by a single one. Hypothesized causes include genetics, physiological, psychological, sociological, and economical. At the most basic level however, obesity is a result of choices.

Another article reviewed dealt with consumption trends. “Dietary Assessment of Major Trends in U.S. Food Consumption, 1970 – 2005[1]” investigated food trends over the last 35 years and their potential link to obesity. While the article covered a variety of food trends, those relating to sugar and sugar consumption were primarily focused on. As of 2005 the average American consumer consumed 142 pounds of sugar each year which is a 19 percent increase since 1970. No guidelines currently exist regarding the appropriate amount of sugar intake although it is suggested that food with little sugars or added caloric sweeteners be consumed. It is recommended that an average adult consume no more than eight teaspoons of sugar daily; the average American consumes 30 teaspoons of sugar each day.

Food Policy

Two articles reviewed focus on government payment and possible policy reform, “Government Payments and Farm Business Survival[1]” and “Perspectives on Farm Policy Reform[1]”. Together these articles indicate that subsidies are purely wealth driven and serve no other purpose than to redistribute wealth from tax payers to farmers. This practice allows corn production to be higher than the market would demand if no policy were in place. Most of these policies benefit larger farms and keep them from failing when they would otherwise cease production. Indeed, the authors of “Payment Limitations and Acreage Decisions Under Risk Aversion: A Simulation Approach[1]” found numerical data to support such claims. The authors found total costs for growing corn in Indiana, a major corn producing state, were higher than the expected total revenues. The same relationship was found to exist in Iowa as well and the authors go on to state such an occurrence would not occur in a free market.

While some believe that such market distortions are unnatural, the authors of “Acreage Decisions Under Risk: The Case of Corn and Soybeans[1]” provide a possible alternative. They believe that corn production may be higher than normal due to cross-commodity risk reduction between corn and soybeans. Farmers can reduce their soybean pest risk by rotating between corn and soybean production every year. This allows them to rid the soil of weeds and pests that commonly plague soybeans at a cost lower than the cost of soybean herbicide and pesticide.

While investigating corn policy it was also necessary to investigate the possible distortions in sugar policy as well in the article “Gains and Losses of Sugar Program Policy Options[1]”. One of the key issues revolving around high fructose corn syrup’s role in the rise in obesity is whether or not sugar policies have contributed to the increased use of high fructose corn syrup. High sugar prices, caused by U.S. sugar policy, have contributed to the increased substitution of corn sweeteners for sugar. The U.S. sugar policy currently relies on a quota policy which the article states is the most expense support option. The demand for sugar depends on the price of sugar and other variables like the price of corn. Sugar quotas have forced sugar prices above market equilibrium allowing corn sweeteners to develop as a substitute. Economies of scale present in the corn market allowed the supply of corn sweeteners to shift outward which caused corn sweetener quantity to rise while prices fell. Total cane sugar consumption has decreased by more than 20% since the 1970s despite a 10% rise in population during that time. This loss in demand is accounted for in the increased demand for corn sweeteners.

Beef Safety In Perspective: by Ashley Mason

Beef Safety in Perspective

by Ashley Mason

This paper was used to satisfy the thesis requirements for an Honors Degree at Oklahoma State University. Ms. Mason graduates from Oklahoma State University in May, 2010 with a degree in agricultural economics and accounting. She can be reached at Her thesis advisor, Bailey Norwood, can be reached at

Food safety is a controversial agricultural topic. Food processors are doing all they can to ensure safe food -- after all, who makes money by making their customers sick? Meanwhile, the cases where consumers do get sick receive enormous attention. Some may even say these cases are exploited by groups wishing to injure the food industry. Though food is safer than at any point in history, there are approximately 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths each year from food-borne illnesses.[1] The average American is further from the farm yet more concerned about how their food is produced. Books by authors such as Michael Pollan, interest in alternative diets such as organic foods and local-grown foods, recent efforts by the Humane Society of the United States to ban conventional livestock production techniques, and documentaries such as Food, Inc. are causing consumer anxiety over the technological changes in meat production over the last fifty years. Though consumers are concerned about many facets of modern livestock production, consumers consistently state that food safety is the most important issue.[2]

The growing interest in food safety, and more specifically food-borne illnesses, makes funding for research studies about food-borne pathogens and their behaviors more readily available. A pathogen of particular interest is Escherichia coli O157:H7. In beef, E. coli O157:H7 (hereafter, simply E. coli) is typically transmitted by contaminated cattle feces that is transferred from the animals' hides to carcasses during the harvesting process. While the pathogen does not make cattle sick, it can be deadly to humans. Research has been conducted to determine what cattle management practices may encourage the growth of E. coli, with particular emphasis on pre-harvest intervention strategies.

In order to understand what practices may increase the risk of E. coli contamination, it is important to understand the steps of the pre-harvest beef production process. In the following description, we will take a look at various studies investigating connections between E. coli contamination and management practices.

A Beef Production Primer

Cattle start their lives at a cow-calf operation. Calving typically occurs in the spring to take advantage of more favorable weather and grass availability. However, calves can be born at any time during the year. During this time, calves graze alongside their mothers in herds on pastures. Though the calves consume exclusively milk at the beginning of their life, within 3 to 8 weeks the calves will begin consuming forage as well. While nursing, approximately 83% of the calves will come into contact with E. coli. The contamination happens before weaning and without any outside animals — and thus, outside contamination — being introduced into the herd.[3] It would seem that calves are infected at a relatively early age, which may present an imposing obstacle for developing effective pathogen management practices. It may be difficult to get ahead of the E. coli contamination if calves are shedding (meaning E. coli are present in the feces) the pathogen within months of their birth. This does not imply that beef is inherently unsafe, but that the presence of pathogens is a natural and expected occurrence, one that is easily negated by with processing technologies and cooking meat thoroughly. Also, the cows in these herds are kept on pasture, with little to no grain supplement, which immediately makes the claims asserting that grain diets are the cause of E. coli contamination in beef questionable.

After the 6-10 month nursing period, the calves are weaned from their mothers. At this point they typically go to a stocker operation[4] where they may graze on young wheat, be cared for in a semiconfined production system, or be raised on one of the many other types of stocker operations until they are about 600 to 800 pounds. The transition from the cow-calf to the stocker operation entails a number of activities that may be related to E. coli contamination. Parting from their mother and being transported to a new location is stressful; this stress weakens the immune system of cattle which, as we shall see, may be related to higher E. coli levels. The calves are also introduced to new cattle, increasing the chance that E. coli will spread to calves previously free of the pathogen.

Indeed, a study conducted on 24 cattle operations at 224 sites finds that stocker calves ready to enter the feedlot are four times more likely to shed E. coli than nursing calves at the cow-calf operation.[5] One might think that the relationship between E. coli and age is caused by the fact that older calves are more likely to reside on a stocker operation than a cow-calf operation, but this is not the case. The researchers find that it is the age of the calf that causes greater E. coli shedding, not differences between the cow-calf or the stocker operation.

After the calves have gained 100-300 pounds at the stocker operation they are sold to a feedlot. The feedlot places the calves into small pens with about 100 other calves of similar age and size. The pens are large enough for the animals to move freely, but small enough that no grass will grow, and manure may accumulate to significant depths before the pens are cleaned. Almost every time the calves lie down they will come into contact with cattle manure, increasing the risk of E. coli entering the harvesting facility via the cattle-hide. In drier conditions the manure is less likely to stick on the cattle-hides, reducing the chance of carcass contamination. It is partly for this reason that most feedlots are located in dry climates, where the lack of rain reduces the extent to which the manure has a muddy composition, reducing the amount of manure brought into the harvesting facility.

Feedlots contribute towards beef value in a number of ways. The number of cow-calf operations is large and spread across substantial tracts of land. Somehow, these millions of calves from almost every region of the U.S. must find their way to a relatively small number of harvesting centers, which can typically accommodate thousands of cattle each day. Additionally, calves tend to be born in similar time periods, which implies that if these calves are raised in a similar manner they will all be ready for harvest at the same time. This is undesirable, as harvesting facilities need to operate year-round. Feedlots provide the service of coordinating the funneling of calves across space and time, so that calves are delivered year-round to the few but large harvesting facilities. By serving as a medium through which stocker calves make their way to harvesting plants, feedlots solve the coordination-across-space problem. Feedlots help manage the temporal-coordination problem by offering high prices when they have few cattle on feed, encouraging producers to remove stocker-calves from pasture earlier, and offering low prices when their cattle numbers are high.

In addition to the coordinating value feedlots provide, they feed cattle a high-grain diet which encourages better tasting meat. This ration typically contains 70-90% grain; such as ground corn, flaked corn, soybean meal, ground milo, and the like. When the cattle reach a weight of 1200-1400 they will be sold for harvest.

Some producers are capitalizing on America’s new healthy living craze by offering beef from cattle that have spent their entire lives on grass or forage based diets. They claim that this meat is lower in overall fat content, but higher in the more healthy types of fat (e.g., omega-3 fatty acids). Recently, there have been claims that grass-fed beef has lower rates of E. coli than conventionally fed beef. The Food, Inc. documentary asserted this as a fact. If only cattle by-passed the feedlot stage, gaining all their weight from forage-based diets, deaths and illness from E. coli contamination would be greatly reduced -- so feedlot critics claim. The purpose of the present research is to explore the link between the feedlot stage of beef production and E. coli. Previous research on the topic is described, as well as other research that helps us understand the extent to which dietary alterations in cattle feed can help reduce food-borne illness in humans.

Exploring the Link Between Cattle Feed and E. Coli Contamination

A study cited in Food, Inc. was conducted with three mature, nonlactating Holstein cows. The researchers varied the proportion of corn in the cattle feed and measured the amount of E. coli subsequently shed in cattle manure.[6] The theoretical rationale for this connection involves the fact that as cattle are fed increasing amounts of grain, the pH in the colon decreases -- E. coli is typically found in the colon of cattle. With a lower pH in the colon, more of the E. coli cells can potentially develop an acid resistance which would enable these cells to better survive in the human digestive tract, and hence cause more human illness. A link is detected in the study, meaning that E. coli is present in larger numbers as corn comprises a larger portion of the feed ration. Moreover, the study finds that E. coli levels can be reduced by 80% after five days on a forage-based (e.g., grass or hay) diet.

The latter result merits further discussion. Even if a switch from grain to forage diets lowers the E. coli count, abrupt changes in cattle feed can shock the digestive system, causing sickness in cattle. Illness impairs the immune system of cattle, making them more susceptible to other forms of contamination (perhaps salmonella) that could also cause human sickness. If the switch to forage-based diets can be performed over a period of time these concerns may be negated, and hence worth considering as a feedlot management strategy. Additional research is also needed to determine the degree to which carcass quality and yield would be affected by a change from a grain-based to a forage-based diet shortly before slaughter.

While this study seems shocking, one must wonder whether a sample size of three cows is sufficient to truly cause alarm. More importantly, the relationship between corn-based diets and E. coli shedding is rarely replicated in other trials. In the study performed by Renter, Sargeant, and Hungerford, they discovered that higher E. coli shedding is really the result of cattle age, and that past studies failed to control for age when exploring the link between corn and E. coli. Finally, it is worth noting that Laegreid, Elder, and Keen, who measure E. coli in calves consuming both milk and forage, tend to find E. coli in almost all cattle. All studies considered, claims that corn-based feed rations encourage E. coli contamination do not appear tenable.

Additionally, bacteria developing acid resistance in the grain-fed cow’s lower pH colon may not be as important as previously suggested. Little is understood about E. coli’s behavior. Some have found that the bacteria are able to become acid resistant relatively quickly in the human digestive system, suggesting that resistance might occur in humans regardless of whether the resistance initially occurred in the digestive tract of cattle.[7] Without a clearer understanding of how the pathogen reacts in different environments, it is difficult to determine the role that acid resistance may play in E. coli’s ability to infect humans.

A Larger View of Food Safety

The questionable link between corn in cattle feed and E. coli contamination suggests there may be better ways to improve beef consumption safety. There are a number of other management practices that can reduce E. coli contamination in human food. Even if corn-based diets encourage E. coli contamination, it might be more effective to combat the pathogen through methods other than reducing corn in the feed ration. These include antibiotics, immunization, probiotics or prebiotics in animal feed, and better beef harvesting and processing intervention activities. Irradiation can also kill pathogens residing in meat without significantly altering the composition of the meat, and only needs to be utilized to treat ground beef, as most pathogen related beef recalls involve ground beef. It is a shame that such an effective technology was given such an unfortunate name. If E. coli contaminates food by jumping from hide to carcass, better hide removal or cleaning techniques might provide the same reduction in contamination at a lower cost. However, each of these possible solutions produces its own unique set of challenges from the point of view of government regulatory agencies, producers and consumers. For example, organic beef would be unable to utilize antibiotics as a preventative practice if they wished to maintain their organic certification. Also, getting these measures accepted by various government regulatory agencies can take many years and requires substantial testing. While these strategies may help mitigate some risk of passing E. coli to consumers, most are many years away from implementation and some may be cost-prohibitive to undertake.

Consumer education may be the most cost-effective route in the fight against food borne illness. By teaching households and restaurants about proper food preparation and disposal techniques, it would be possible to put the power to end food-borne illness into the hands of consumers themselves for much lower costs than attempts to mitigate the risk earlier in the production cycle. In order to alleviate some of the fears associated with modern beef harvesting practices, we have found that tours of these modern facilities tend to make a favorable impression. They are also easy to arrange.

Though it may seem irresponsible to make decontamination of beef the responsibility of the consumer, the reader should note that consumers do not desire risk-free food consumption. Just as consumers drive cars every day, knowing that the very act entails some chance of death, millions of hamburgers are eaten everyday with the knowledge that this consumption incurs some risk. The consumer who prefers ground beef any way other than well-done knows that doing so increases the risk of illness. Daily life involves trading some amount of safety for convenience and price. The optimal risk of food illness is not zero risk. Consumers accept slightly greater risk in return for lower food prices, which consumers may use to reduce risk of harm in other ways. Spending less money for beef so that there is more money for prescription drugs may, ultimately, result in greater health. Or, they may spend the money on something they enjoy that increases risk of death even more – that is their choice. The job of food processors is to provide the level of risk that consumers want, not zero risk.

In order to find the best solution to help reduce or eliminate E. coli infections, every step of the production cycle from farm-to-fork should be carefully evaluated for potential improvement and implementation costs of recommended management practices should be considered.


It seems that food-borne illness is making the headlines more often. Because food safety is of great concern to consumers, individuals who dislike beef production for other reasons attempt to reduce beef demand by making beef appear to pose a significant health risk. It is not a coincidence that individuals who dislike the level of animal welfare, greenhouse gas emissions, and nutrient runoff associated with beef production are quick to make beef seem unsafe and unhealthy. Such individuals are often influential, and so it is important that these criticisms are addressed when they are unfounded.

While some evidence suggests that the use of corn in feedlot feed rations may be associated with higher levels of E. coli contamination, there is also evidence suggesting otherwise. When the documentary Food, Inc. discussed the study of three cows making this link, it failed to mention the other studies finding otherwise. Nor did it mention the other, potentially more effective methods of reducing food contamination. The fact that Food, Inc. reports only the studies making the feedlot stage of beef production appear undesirable suggests that it is more concerned with demonizing beef than it is with consumer education. Ignoring facts can often make for a better story, but as John Adams stated, “facts can be stubborn things.”

[1] ASAS Centennial Paper: Developments and future outlook for preharvest food safety. S. P. Oliver, D. A. Patel, T. R. Callaway, M. E. Torrence; Journal of Animal Science, Vol 87, No 1, January 2009, 419-437.

[2] Norwood, Lusk, and Prickett. October 8, 2007. “Consumers Share Views on Farm Animal Welfare.” Feedstuffs. 79(42):14-16.

[3] “Prevalence of Escherichia coli O157:H7 in range beef calves at weaning.” W.W. Laegreid, R.O. Elder, and J.E. Keen. Epidemiology and Infection. (1999), 123, 291-298.

[4] “Stocker” and “feeder” calves are two words used to describe calves that have recently been weaned. There are some distinctions between the two words. For an excellent treatment of these terms, see: Peel, D. 2003. “Beef Cattle Growing and Backgrounding Programs.” The Veterinary Clinics: Food Animal Practice. 19:365-385.

[5] “Distribution of Escherichia coli O157:H7 within and among cattle operations in pasture-base agricultural areas.” David G. Renter, DVM, PhD; Jan M. Sargeant, DVM, PhD; Laura L. Hungerford, DVM, MPH, PhD; American Journal of Veterinary Research, Vol 65, No. 10, October 2004, 1367-1376.

[6] “Grain Feeding and the Dissemination of Acid-Resistant Escherichia coli from Cattle.” Francisco Diez-Gonzalez, Todd R. Callaway, Menas G. Kizoulis, James B. Russell; Science, Vol 281, September 1998, 1666-1668. Note: although this study considers all types of E. coli, E. coli O157:H7 tends to be positively correlated with E. coli in general.

[7] “The adaptive response of Escherichia coli O157:H7 in an environment with a changing pH.” R. de Jonge, K. Takumi, W. S. Ritmeester, F. M. van Leusden; Journal of Applied Microbiology, Vol 94, 2003, 555-560.

Thursday, May 6, 2010

How Do College Students Describe Great Teachers?

With two coauthors, I have completed a draft manuscript describing the results of personal interviews and questionnaires providing us with an illustration of how college students describe great college teachers. The best part of the paper is Figure 2, which is a diagram illustrating the attributes of great college teachers, the consequences of those attributes that students desire, and the terminal values driving the preferences.

The abstract is below. A collection of similar articles can be found at the Effective Teaching and Advising link at

The Attributes and Attribute-Consequences of Great College Teachers
by Mary Wilson, Carol Cook, and Bailey Norwood

Very Short Abstract

In personal interviews and questionnaires, students describe great college teachers as those who are dynamic lecturers, clear communicators, and make sincere efforts to relay their concern for students and student learning. Driving these preferences is students' desire to commit to class, improve class focus, and learn the material.

Wednesday, May 5, 2010

In Defense of High Grades

Note: this entry is not in response to any conversation or individual. Teacher B is not me, and Teacher A is not one of my colleagues. Seriously, this doesn't refer to any specific event or person. Only a few of my friends read this blog, so I want to make that clear :)

It is that time of year when professors begin discussing among themselves the extent to which they can or should assign high grades. We oversimplify the decision: easier teachers give higher grades, and tougher teachers give lower grades. Teachers who give low grades are resentful of those who give higher grades. The "easy graders" make them look bad, and [supposedly] are not challenging the students.

In this context, grades are thought to stem from one source only: the toughness of the teacher. Grades are not thought to reflect the learning that occurs. We know this because when universities implement assessment programs, grades are completely ignored as indicators of learning.

In this essay I propose that we think about grades in a more realistic framework. I propose that grades should be assigned based on the learning that occurs, and that learning is the result of both the students' and teachers' effort. Below, I describe a few scenarios where Teacher A and Teacher B are equally "tough", but Teacher B has earned the right to assign higher grades.

But first: I fully recognize that there is such things as "easy" and "hard" graders. The purpose of this essay is to encourage us not to see differences in grading as due to the easy/hard grader factor, but are also influenced by teacher efficacy and effort.

Scenario 1 - Teacher B Is Better
Teacher A enjoys teaching and demands that students learn the material if they are to obtain a high grade. However, Teacher A rambles in class, such that the students are unsure what is relevant for tests and what is not. Teacher A does not provide study guides for tests, and instead states that, "Everything covered in class and in the readings is fair-game." Students know that this covers a vast amount of material. The expected return to studying is low, and so they do not study and do not learn. They score badly on the tests.

Teacher B is the oppose. This teacher also requires significant learning for students to achieve a high grade, but he puts forth great effort to make sure they actually learn. He sticks to his objectives, he is clear about what is relevant for tests and what is not. Study guides are provided; they are specific and detailed. Students of Teacher B expected a higher return to studying -- they actually know what is on the test! -- and they study hard. Students indicate a high degree of learning by doing well on the tests. Significant learning occurs, and Teacher B has earned the right to assign higher grades.

Scenario 2 - Teacher B Works Harder
Teacher A does not hold any study sessions outside of class, while Teacher B charges his teaching assistants with the job of holding a study session two nights before the exam, and he holds a second study session the night before the exam. The expected return to studying is higher when you can study with the teacher at your side to answer questions. Students study harder, answer more questions correctly, and thus have learned more. Significant learning occurs, and Teacher B has earned the right to assign higher grades.

Scenario 3 - Let Them Fail, Then Repeat
There are very few billionaires that haven't lost a lot of money at some point. Every business confronts frequent failures -- that is how they learn what consumers wish to buy and learn their efficiency relative to their competitors. Life is full of second chances. Moreover, we learn best when we are allowed to fail. Failure is salient; failure is emotional. Failure is articulate because you know exactly why you failed. Failure is essential to learning.

Teacher B puts forth considerable effort to allow students to redeem their failures. After they perform poorly on a test, he allows them to retake it. However, they must attend 90% or more of classes and attend two study sessions before the first exam. This ensures students do not simply choose to not study for the first exam, get to see the exam, and then study for the retake. The retake is held outside of class, late at night. Students must work hard for the opportunity to retake. The expected return to studying is higher, students study harder, answer more questions correctly, and thus have learned more. Most study twice for the same exam. Significant learning occurs, and Teacher B has earned the right to assign higher grades.

When they do retake, they understand exactly what they did wrong the first time, and they learn to overcome that barrier. The return to studying is higher, students study more, they indicate greater learning on the exams, and Teacher B has earned the right to assign higher grades.

My final question is this: If Teachers A and B existed and were exactly as described above, should Teacher B feel ashamed at giving higher grades?

I have often said my dream is to teach a class where everyone learns more than 90% of the material and I gave all A's in response. If I did this, and the only thing other people saw was a class of students who all received an A, would I become labeled an "easy grade"? The answer is yes. The purpose of this essay is to encourage us to instead answer: I need to know more about the class than just the grades that were given.