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OM in the News: Do You Hate Waiting in Line?

October 29, 2020

Conventional wisdom says that the fastest-moving line is a single “pooled” line. We have long subscribed to this mathematical approach with Models A and B in Module D, Waiting Line Models in our OM text. But a new study, reported in The Wall Street Journal (Oct, 26, 2020), just found that splitting the pool into individual lines made them move faster.

The researchers looked at patient wait times and length of stay in the ER of a California hospital. They found that when the hospital switched from a pooled line to a dedicated-queue system in which patients were assigned to a specific doctor, average wait times decreased 9% ( by 39 minutes) and lengths of stay decreased 17%.

Single lines may not be the fastest in knowledge-intensive fields.

With a dedicated-queue system, physicians could see who they were helping, who in the waiting room had been assigned to them and exactly how long their individual queue was. The doctors seemed to feel more ownership when they could see which and how many patients were assigned to them.

But would service providers in other industries behave the same way as? The study concluded that a dedicated queue would also speed up wait times in fields that are knowledge-intensive and have high levels of customer ownership, such as medicine, personal banking or places like the Apple Genius Bar.

“The phenomenon is not expected to translate to anonymous call centers or other settings where the service provider doesn’t have a relationship with the customer or the service is very routine, like at a grocery checkout or a factory with machines,” says one of the researchers in a forthcoming article in the journal Operations Research. “Companies may want to look at their organizational culture, seeing where there is room to encourage more customer ownership, and consider ways to change to a dedicated-queue configuration to achieve shorter wait times. Encouraging customer ownership by dedicating assignments to each server when planning queue configurations might shorten the wait and service time.”

Classroom discussion questions:

  1. Explain the difference between Models A (M/M/1) and B (M/M/s).
  2. What model is being described in this study?

OM in the News: The Megaship Capacity Disaster

October 27, 2020

In 2006, the Emma Maersk left her shipyard. The length of 4 soccer fields, Emma was far larger and more expensive than any container ship ever before. She was a bet on globalization: By transporting a container more cheaply than any other vessel afloat, she and her 6 sister ships were expected to stimulate even faster growth in international trade, lowering the cost of moving goods through the supply chains that had reshaped the global economy. But the opposite occurred. Emma and the even larger ships that followed in her wake became a nightmare.

Container ships are the workhorses of globalization. Operating on regular schedules— an identical vessel departs Shanghai every Wednesday, stops in Singapore 9 days later and arrives in Antwerp 5 weeks hence, with tight connections to barges and freight trains—intermodal container transport gave manufacturers and retailers the confidence to plan tightly organized long-distance supply chains. Emma and her sisters’ size was expected to give shipping an immense cost advantage. Maersk forecast in 2006 that the demand for container shipping would double by 2016.

The container ship Emma Maersk in Hamburg

But the boom never occurred. Instead, international trade collapsed in 2008-09, and when it picked up again, its growth was far weaker than before. By the early 2010s, there simply weren’t enough container loads to fill all the new capacity, wiping out the cost advantages of larger vessels. And discharging and reloading megaships took longer as well, with more boxes to put off and on, while giant shoreside cranes needed to reach a greater distance to pick up a container. Thousands more boxes multiplied by more handling time per box added days to a port call. Delays were legion.

Once, container ships would have been able to make up those delays en route. But to save fuel and reduce greenhouse gas emissions, vessels must now travel at 17-18 knots instead of 24-25 previously, adding several days to a long ocean voyage. By 2018, 30% of the ships leaving China departed late.

“With proper accounting,” concludes The Wall Street Journal (Oct. 24-25, 2020), “the globalization of manufacturers’ supply chains no longer seems such a bargain.”

Classroom discussion questions:

  1. How would the land side of international logistics be impacted by this issue?
  2. What capacity strategy best fits shipping companies now? (Hint: see Figure S7.6 in your Heizer/Render/Munson text)

OM in the News: Protecting Covid-19 Vaccines from Theft

October 25, 2020

Health authorities, hospitals and pharmaceutical companies are storing Covid-19 vaccines in secure, undisclosed locations and taking other steps to protect the shots against a looming threat: theft.

As the leading vaccine candidates advance closer to use, vaccine makers such as Pfizer are deploying GPS software for tracking distribution and plotting fake shipments in dummy trucks to confuse criminals. Glassmaker Corning  is equipping vials with black-light verification to curb counterfeiting. And some hospitals expected to be among the first vaccination sites are beefing up their pharmacies’ security systems.

Initial vaccine supplies are expected to be limited, with some shots gaining authorization as early as November.

The goal is protecting the shots against professional thieves who have a long history of targeting valuable medicines, and have pilfered Covid-19 tests, masks and other personal protective equipment during the coronavirus pandemic, reports The Wall Street Journal (Oct. 22, 2020).

The government has arranged for U.S. marshals to accompany shipments of vaccines, which are currently stored at undisclosed locations, once the shots are authorized for distribution. Despite such measures, logistics specialists worry the shots could be vulnerable to theft at weak links in the supply chain, such as distribution centers, truck stops and hospitals with lax security.

Though drugmakers have been producing doses, initial supplies are expected to be limited, making any shot a coveted commodity. Industry experts are concerned they could be intercepted by sophisticated criminals, foreign governments or individuals eager to get vaccines before prioritized groups. Over the past 5 years, world-wide incidents such as theft and counterfeiting of pharmaceutical products rose nearly 70%.

Classroom discussion questions:

  1. Why will this vaccine’s distribution be a significant challenge?
  2. Table 11.3 in your Heizer/Render/Munson text provides a list of 10 supply chain risks. Which apply in this case? How?

OM in the News: Shipping Capacity Sold Out for the Holidays

October 22, 2020

One holiday item is already sold out: shipping capacity. Both FedEx  and UPS have told shippers that most of their capacity is already spoken for, and that any extra trailers with holiday orders will have to wait to be picked up.

“There will be days within the holiday season where the industry will be over capacity,” said one FedEx exec. The outlook has sent retailers on the hunt for alternatives with little luck. Smaller carriers also booked up their capacity for the holidays months earlier than usual and aren’t taking new customers.

The capacity shortfall could average 7 million packages a day between Thanksgiving and Christmas, reports The Wall Street Journal (Oct.19, 2020). Total shipping capacity for the industry will be 79.1 million parcels a day during that period, with 86.3 million packages looking for space.

Carriers and their shippers spend months planning for the holiday season and hone their forecasts for the number of packages they expect to ship. The two sides decide items like weekly shipping forecasts and how many trailers the carriers may need to pick up from their loading docks each day. Any deviation from the estimate can result in higher rates per package or penalties to compensate the carrier for needing to marshal more resources.

In previous years, shippers could usually find space to ship if online sales blew through expectations, though it would come at a premium to rates that had been negotiated. Now that doesn’t exist. The primary reason for this year’s capacity shortage is that carriers already have been operating near maximum capacity for months as consumers stayed home, avoided stores and shopped online.  Carriers can’t quickly boost capacity with new facilities as it often requires a multiyear planning process.

Classroom discussion questions:

  1. What might carriers do to “manufacture” some extra capacity? (Hint: see the section called Capacity on pages 308-313 in Supp. 7 of your Heizer/Render/Munson text).
  2. What can retailers do?

OM in the News: Seven Reasons Why It’s Hard to Find a Can of Corn

October 19, 2020

The front page of The Wall Street Journal (Oct. 14, 2020) highlights yet another fallout from the pandemic. Just when we thought there were enough paper, pasta, and PPE supplies, we are given 7 reasons the coronavirus has hobbled the supply chain for canned corn.

Problem 1: Sweet Corn Supplies Are Finite. Corn for canning makes up the smallest portion of the U.S. crop. Fresh corn is canned right after the harvest in late summer, and that yield is the entire supply for the year.

Problem 2: Land Is Limited. The small number of farmers who specialize in growing sweet corn have set planting plans for the year already.

Problem 3: Corn Is Only Harvested Once a Year. The March surge in food demand led some consumers to stockpile food. Retailers quickly blew through inventories. The next corn harvest is months away, making it hard to restock.

Problem 4: There Aren’t Enough Trucks. Trucking companies shrank their fleets last year to improve profitability. The fleet that remained was too small to handle the March surge in demand. 

Problem 5: Truckers Are Rejecting Contracts. The decrease in trucking capacity drove up prices, prompting some transportation companies to reject existing contracts.

Problem 6: Corn Is Irreplaceable. Food makers can substitute ingredients in some products, like soup or boxed dinners, when an ingredient is scarce. That’s not an option for the main ingredient in foods that are canned individually, like peas or corn.

Problem 7: Hoard Mentality. Sparse shelves begot empty shelves, as people hoarded, fearing shortages. Many products haven’t returned to pre-pandemic inventory levels. Out-of-stock levels for groceries have risen recently, indicating that supply-chain problems persist.

Canned-corn brands expect to increase production 25% over last year. But retailers are starting off with lower inventory, and they don’t know if they’ll be able to keep up with demand through the winter season.

Classroom discussion questios:

  1. What are the OM issues involved here? (Follow the 10 OM decisions outlined in your Heizer/Render/Munson text).
  2. What control do grocers have, if any?

OM in the News: J and J’s Circular Supply Chain for Packaging

October 16, 2020

Converting bottles to recycled plastic. Redesigning baby lotion bottles to ditch the pump. Swapping out the black Listerine cap for a clear resin one. Reducing the dimensions of cartons holding Carefree pads to use less paper. Johnson & Johnson’s goal is to use 100% recyclable, reusable or compostable plastic packaging, and recycled paper and pulp-based packaging by 2025, reports Supply Chain Dive (Oct. 13, 2020) .

The company will spend $800 million to make these packaging changes in an effort to convert its consumer health products packaging to sustainable options. To make a package fully recyclable, every part must be recyclable, including the label. (Some bottles use a label which can cause recycling issues). The packaging should also be compatible with the recycling process, likely a reason J&J is looking to remove the pump from some products. The pump needs to be discarded before recycling the bottles, and not all consumers do this.

J&J is planning to change Listerine’s black cap for a clear resin one, because clear plastic can be reprocessed into more forms than black plastic.

But sustainability isn’t the only consideration in packaging. The packaging has to be functional. There’s a greater issue if the packaging causes product damage in an effort to use more sustainable packaging materials. Plastic color can also change to generate higher recovery values.

Instantly reducing supply chain waste starts with using less material. Package optimization testing can help determine the least amount of material needed to effectively ship products. Looking at the carbon footprint is also part of the sustainability process. Usually, the less material used, the lower the carbon footprint.

These efforts all support the circular economy that we describe in Supp.5, “Sustainability in the Supply Chain” on pages 197-200.

Classroom discussion questions:

  1. Select three products and evaluate their packaging. How could it be more sustainable?
  2. How have hotels become more sustainable conscience?

Teaching Tip: Teaching Covid and OM

October 14, 2020

We think that when you review your lecture outlines on supply chains and OM this semester and in Spring, you may find the need for some reworking. As a matter of fact, “the disruption of the pandemic in 2020, coming on top of the uncertainties surrounding trade wars, has helped turn OM/SCM into a theme of growing concern for businesses, business schools and wider society,” reports Financial Times (Oct. 8, 2020). 

Shortage of bikes at Walmart during the pandemic

Cross-border trade comprised just 5% of GDP in the mid-20th century but today it is closer to 50%. That has been accompanied by a rapid extension of global supply chains with products and their components often manufactured in numerous countries, driven by cheap labor and easier transport and communication.

London Business School Prof. Jeremie Gallien states: “supply chain management used to be perceived as a ‘somewhat niche component’ of the business education curriculum. In the aftermath of the first Covid wave, many firms found themselves either fighting for survival or realizing the importance of increasing their resilience to reduce the costs they will incur during the next disruption It is harder to get student interest if one teaches supply chain concepts without being able to relate to Covid-19.”

Jay, Chuck, and I agree. And as authors of the top selling OM text in U.S. and global markets, we are here to help make your lectures more timely and relevant. We hope you will incorporate Table 11.3 (“Supply Chain Risks and Tactics”) in Ch. 11 (p. 450) and the section called “Evaluating Disaster Risk in the Supply Chain” in Supp. 11 (p.472-3) into your syllabus.

And to bring more currency into case discussions, we have just written a new case called Premier Bicycle’s COVID Problem. This case will appear in MyOMLab’s Spring edition, but here is the link should you want to preview the case or teach it this term.

 

OM in the News: The Challenge of Delivering Covid-19 Vaccines

October 12, 2020

UPS is combining multiple refrigerators at its airport hubs to store vaccines in transit.

Just 2 weeks ago, Prof. Jeff Heyl delivered his Guest Post from New Zealand saying 8,000 fully laden Boeing 747’s would be needed to deliver a single dose of a Covid-19 vaccine to the world’s population. The Wall Street Journal (Oct. 6, 2020) asks: “If just 50 million doses were available today, could we distribute them?” The answer is almost certainly ‘No,’ states the head of the International Air Transport Association.

The pandemic has revealed shortcomings in global supply chains and forced business to make logistics a bigger strategic priority. Nonetheless, the air-cargo industry is making plans for delivering as many as 20 billion Covid-19 vaccination doses, even before regulators have approved any of the treatments under development. (Pharma companies say they expect the bulk of vaccines to be transported by air.)

Carriers such as FedEx, DHL,and UPS have started preparations such as introducing new temperature-monitoring systems to track future vaccine shipments.  They are building “freezer farms” combining multiple refrigerators at their airport hubs to store vaccines in transit. Vaccines have to be kept at a very low constant temperature throughout the journey to prevent spoiling.

Cargo flights are fast filling up through February with bookings for consumer electronics, apparel and industrial parts through the holiday season and new year. Cargo executives said they expect it will take 2 years for a vaccine to reach all of the world’s population, with particular challenges in some emerging markets where infrastructure is limited. Fortunately, the air-cargo industry isn’t starting from scratch. Pharma products have been one of the fastest-growing and most profitable cargo types over the past decade.

Classroom discussion questions:

  1. Why is this such a complex logistics issue?
  2. What OM approaches can be deployed to increase the distribution efficiency?

Good OM Reading: McKinsey’s Report on Supply Chain Shocks–Part 2

October 9, 2020

Companies need an understanding of their exposure, vulnerabilities, and potential losses to create resilience strategies for their supply chains, writes McKinsey Global Institute in a new report. Targeted measures taken before an event occurs can mitigate the impact of a shock or speed time to recovery. As more physical assets are digitized, for example, companies will need to step up investment in cybersecurity tools and teams.


One of the most important steps is building more redundancy into supplier networks. Relying on a single source for critical components or raw materials can be a vulnerability. In fact, even if a company relies on multiple suppliers, they may be concentrated in the same place. Taking the time to identify, prequalify, and onboard backup vendors comes at a cost. But it can provide much-needed capacity if a crisis strikes. Auditing and diversifying the supply chain can have the added benefit of reducing carbon intensity, and raising environmental and labor standards.

One way to achieve supply chain resilience is to design products with common components, cutting down on the use of custom parts in different product offerings. Auto manufacturers are perhaps the most advanced in this regard, having implemented modular manufacturing platforms that share components across product lines and production sites.

Physical assets may need to be hardened to withstand natural disasters. In regions that are vulnerable to worsening hurricanes and storm surges, this may involve installing bulkheads, elevating critical machinery, adding more waterproof sealing, and reworking drainage. Plants located in earthquake-prone areas may need seismic retrofitting. Companies can also build more redundancies into logistics.

Classroom discussion questions:

  1. What protections can be added to manufacturing plants?
  2. Refer to Table 11.3, “Supply Chain Risks and Tactics'” on page 450. What additions could you provide relating to the current pandemic?

OM in the News: Countering China’s Dominance of Key Minerals

October 7, 2020

The U.S. government is ramping up efforts to secure minerals critical to modern technology but whose supply is dominated by China—a stranglehold that could take years to break , writes The Wall Street Journal (Oct. 6, 2020).

In recent years, the U.S. and other Western nations have invested in projects to mine these resources—essential for the production of electric vehicles, cellphones and wind turbines—an effort these countries are now accelerating given how far they still trail China.

Last week President Trump signed an executive order to speed the development of mines. Miners welcomed the move, but caution it takes around 10 years to set up a mine and that the West also needs to develop the capability to process these resources into the materials used in final products.

Rare-earth elements are one of the 35 types of minerals that the U.S. government has deemed critical to economic and national security. The U.S. imports 80% of its rare-earth elements from China. For 14 of the 35 critical types of minerals, the U.S. has no domestic production. China has built its dominant position because of their abundance there and the country’s more lax environmental laws make it easier to mine them. It today dominates the entire supply chain.

Up until the 1980s, the U.S. was the world’s biggest producer of rare earths and created the technology to process them, but now has only one producing mine and no processing plants. (That one is California”s Mountain Pass mine–shown in the photo)-

Classroom discussion questions:

  1. Why are these rare minerals an OM issue?
  2. Relate the new mining push to the “Triple Bottom Line” discussed in Supp. 5 on p.195-6 of your Heizer/Render/Munson text.

Good OM Reading: McKinsey’s Report on Global Value Chains–Part 1

October 5, 2020

In recent decades, value chains have grown in length and complexity as companies expanded around the world in pursuit of profits. Since 2000, the value of intermediate goods traded globally has tripled to more than $10 trillion annually. Businesses that successfully implemented a lean, global model of manufacturing achieved improvements in inventory levels, on-time-in-full deliveries, and shorter lead times.

However, these OM choices sometimes led to unintended consequences.. Intricate production networks were designed for efficiency, cost, and proximity to markets but not necessarily for risk. Now they are operating in a world where disruptions are regular occurrences. “Companies can now expect supply chain disruptions lasting a month or longer to occur every 3.7 years, and the most severe events take a major financial toll,” reports the McKinsey Global Institute. This new research study, which we summarize in a two-blog series, explores the profound shocks facing value chains from financial crises, terrorism, extreme weather, and, yes, pandemics.

Some manufacturers will use technology and devise other strategies to come out on the other side of the pandemic more agile and innovative. McKinsey reminds us that the COVID pandemic is only the latest in a series of disruptions. In 2011, a major earthquake and tsunami in Japan shut down factories that produce auto components, halting assembly lines worldwide. It also knocked out production of silicon wafers, on which semiconductor companies rely. 

 Forty weather disasters in 2019 caused damages exceeding $1 billion each. And the number of ransomware attacks doubled from 2018 to 2019. Interconnected supply chains and global flows of data, finance, and people offer more “surface area” for risk to penetrate, and ripple effects can travel across these network structures rapidly. Companies tend to focus much of their attention on managing the types of shocks (like trade disputes, product recalls, data breaches, or logistics disruptions) they encounter most often. COVID is a reminder that outliers may be rare—but they are real possibilities that companies need to consider in their decision making.

Classroom discussion questions:
1. Relate each of the major headings in Supp. 11 (Supply Chain Management Analytics) to the COVID pandemic.

2. What changes might an operations manager make in response to this report?

Good OM Reading: “The Toyota Way,” by Jeff Liker

October 3, 2020

In the 1990s Toyota’s principles of production equipment became “simple, slim, and flexible,” which some people might interpret as “go slow and be cautious in adopting new technology.”  In today’s age of lightning speed in the digital world, Jeff Liker’s new book, The Toyota Way (Oct., 2020) says that would be a mistake. His message is: “adapt technology that supports your people and processes.” Where are real needs that technology can address to help achieve corporate goals? This is a question of pulling technology based on the opportunity, instead of pushing the technology because it is the latest fad. The key issue, writes Liker, is to avoid the temptation to buy and implement the latest gee-whiz digital tools, and instead to thoughtfully integrate technology with highly developed people and processes.

Toyota’s largest supplier, Denso, in Japan, has made remarkable progress in adapting real time data collection, the Internet of Things (IOT), and data analytics to support lean systems and amplify kaizen. At the center of Denso’s approach is people, and their ability to sense reality and think creatively.  Denso demonstrates that technology has the greatest potential when there is a culture of continuous improvement and the people are highly developed. Denso operates on the belief that IOT does not cut people out of the loop, but rather provides superior information to people about the process. The power of big data and AI is to give the operator information just-in-time that they previously could only guess at. But Denso expects the operator to use that information creatively to find the root cause and solve the problem through kaizen. Denso calls this “collaborative creation and growth of human, things, and equipment.”

Toyota’s system, says Liker, is about forcing people to think deeply to solve problems. Will computer systems make us lazy thinkers?  How can we marry the powerful information coming out of the computers with the creativity of people in developing and testing ideas for improvement? This is a book worth sharing with your students when you cover Chapter 16, Lean Operations.

OM in the News: Berkeley Bans Junk Food in Grocery Checkout Aisles

October 1, 2020

The city of Berkeley, California, is trying to make its residents healthier, reports CNN.com (Sept. 25, 2020). As part of a health initiative, Berkeley is getting ready to become the first city in the US (in March, 2021) to require large grocery stores to stop selling junk food and candy in checkout aisles. So now instead of candy and soda and other high calories items, shoppers can expect to see fresh fruit and whole grain alternatives at checkout counters.

“Placement of unhealthy snacks near a register increases the likelihood that customers will purchase these foods and drinks when willpower is weak at the end of a long shopping trip,” said a City Council member. The new rule will affect at least 25 retailers in Berkeley. These include Whole Foods, CVS, Walgreens and Safeway.

Stores can still sell candy and soda, just not at a child’s eye level in the checkout. The council said the shift to selling more healthy products at checkouts will still be profitable for stores because data shows customers are looking for more low sugar and low sodium products anyway. “The idea of healthy checkout is that it offers parents more opportunities to say yes to their kids, and it also helps us to re-envision what treats are,” said a member of Berkeley’s sugar-sweetened beverage commission. Retailers in test cases around the country and in California have seen dramatic increases in sales of healthy foods since they changed their checkouts to include more fresh options in displays.
As we point out on page 374 of Chapter 9, layout of retail stores is a scientific OM issue whose “objective is to maximize profitability per square foot of floor space.” But checkout counter locations, valuable because of their high exposure rate, are traditionally sold to food manufacturers by the inch!
Classroom discussion questions:
1. Is it a good strategy for governments to dictate supermarket product layouts?
2. Why is this an OM issue?

OM in the News: Grocers Stockpile “Pandemic Pallets” Ahead of Winter

September 29, 2020

Grocery stores and food companies are preparing for a possible surge in sales amid a new rise in Covid-19 cases. Supermarkets are stockpiling groceries and storing them early to prepare for the coming months, when some health experts warn the country could see another widespread outbreak of virus cases and new restrictions. Food companies are accelerating production of their most popular items. These changes, a reaction to the sudden and massive shortages grocers experienced in the spring, amount to a shift from the JIT inventory management practices that have guided the retail business for decades, writes The Wall Street Journal (Sept 27, 2020).

Now, food sellers are stockpiling months, rather than weeks, worth of staples such as pasta sauce and paper products to better prepare for this winter, when people are expected to hunker down at home. Retailers are expanding distribution capacity, augmenting warehouse space and modifying shifts.

Associated Food Stores (a coop of over 400 stores) recently started building “pandemic pallets” of cleaning and sanitizing products so it always has some inventory in warehouses. The Giant and Food Lion chains already have holiday inventory in their warehouses. Those chains are also storing 10-15% more inventory than they did before the pandemic to ensure they won’t run out of fast-selling items. Still, some products such as cleaning wipes and canned vegetables remain hard for stores to obtain, partly because of continued high demand and because manufacturers are still trying to keep up.

General Mills said it hasn’t caught up with demand for Progresso soup, Betty Crocker cake mixes and Pillsbury refrigerated dough. It is increasing its production capacity, but the entire industry is still struggling to rebuild inventory on similar items. Manufacturers have given priority to making their fastest-selling products, which has helped some items recover inventory in recent months. Walmart is overriding its grocery-ordering algorithms to build up extra inventory now, after decades of becoming increasingly lean. Coke is  still making fewer varieties of drinks to meet demand for its top beverages.

Classroom discussion questions:

  1. Why a change from the JIT inventory approach?
  2. Why is there still a shortage of some inventory items?

OM in the News: How the Famous Book, “A Million Random Digits,” Wasn’t So Random

September 27, 2020

“A Million Random Digits” was the largest table of random digits ever published

For 65 years, Rand Corp.’s reference book “A Million Random Digits with 100,000 Normal Deviates” has enjoyed a reputation as the go-to source for random numbers. Simulation and sampling problems are facilitated by these random numbers, as are many problems in our text. (See Table F.4 on page 799 of Module F, Simulation, for a small excerpt).  As Gary Briggs of Rand Corp. noted in The Wall Street Journal (Sept. 25, 2020) “it was really hard to get really high-quality random numbers.”

Well, after all of these years and worldwide usage, Briggs found some errors. While many of us would consider the errors minor, he found them “soul crushing,” adding, “the idea that I’m finding errors that we’ve ignored for 65 years is upsetting.” Before modern computers, he says, “it was really hard to get high-quality random numbers.” The book changed that for a generation of pollsters, lottery administrators, market analysts and others who needed means of drawing random samples.

Here is a bit of history: Rand collected a million digits using Douglas Aircraft Co.’s machine that registered random fluctuations in voltage and converted them into strings of 1s and 0s. A circuit board converted sets of 1s and 0s into digits 0 to 9, which a third machine translated into holes punched into 20,000 computer cards. Technicians fed the cards into an IBM data-processing machine, which generated a million-digit number filling 400 pages of tables.

How did the digits lose their “randomness?” Briggs thinks a technician dropped cards and put them back in the wrong order!

“A Million Random Digits,” by the way, became less relevant as powerful computers generated instant randomness.

Classroom discussion questions:

  1. How much difference would such errors in the Rand book make in your problems in Module F?
  2. Why are random numbers an important tool?