N34 | Macro Paper Warehouse

Technology Transfer and Early Industrial Development: Evidence from the Sino-Soviet Alliance

Mon, 01 Jan 0001 00:00:00 +0000

This paper estimates the causal effect of technology and knowledge transfers on early industrial development using the Sino-Soviet Alliance of the 1950s as a natural experiment. Between 1950 and 1957, the Soviet Union supported the “156 Projects” — 139 approved civil projects for constructing technologically advanced, large-scale, capital-intensive industrial facilities in China. The intended program comprised two components: a “basic” transfer of Soviet state-of-the-art machinery and equipment (including blueprints, site surveys, and plant construction assistance), and an “advanced” know-how transfer involving Soviet experts residing in Chinese plants for roughly three years to train engineers and production supervisors in organizational, technological, and planning methods. Total investment amounted to approximately $80 billion in 2020 figures (45.7% of Chinese GDP in 1949).

Identification exploits idiosyncratic delays in project completion caused by Soviet production capacity constraints, insufficient experts, translator shortages, and miscommunication — factors documented in historical records as unrelated to project-specific characteristics. When the Sino-Soviet Split in 1960 abruptly ended the program, all 139 plants had been built but differed in what transfers they had received: 46 received both machinery and know-how (advanced), 46 received only machinery (basic), and 47 received neither (comparison). The paper verifies, via ANOVA tests, multinomial logit models, balancing regressions on 26 plant characteristics, pre-trend tests, and Oster (2019) selection-on-unobservables bounds, that the three groups were statistically equivalent prior to receiving the Soviet transfers.

The primary data source is plant-level annual reports from the Steel Association covering 94 steel firms (1,410 plants) from 1949 to 2000, matched to 304 steel plants across the 156 Projects. Supplementary sources include the declassified 1985 Second Industrial Survey (7,592 largest Chinese firms) and the China Industrial Enterprises database (1998–2013, over 1 million firms).

Three main results emerge. First, receiving only the basic (machinery) transfer had positive but short-lived effects: output of basic plants peaked at 14.7 percent above comparison plants six years after receiving Soviet machinery, then declined monotonically and became statistically insignificant after 20 years — consistent with the estimated 15–20 year life cycle of Soviet capital. Second, the advanced transfer had large and persistent effects: advanced plants’ output rose 8.4 percent relative to basic plants within two years, 19.7 percent within 20 years, and 49.5 percent cumulatively after 40 years. TFPQ of advanced plants reached 47.9 percent above basic plants after 40 years. These magnitudes held across industries in 1985 and 1998–2013 data, where value added of advanced firms was 41.4–52.0 percent higher and TFPR 39.5–49.3 percent higher than basic firms. Third, the program generated horizontal spillovers (12.9 percent higher output, 12.4 percent higher productivity for steel plants in counties hosting advanced plants) and vertical spillovers (16.4 percent productivity gain for supply-chain firms in counties of advanced nonsteel plants), with spillover effects conditional on post-1990s market liberalization to materialize in private firms.

The mechanism driving persistence is the accumulation of organizational and human capital during the advanced transfer, which enabled advanced plants — uniquely — to develop new production processes endogenously, home-fabricate continuous casting furnaces to replace obsolete Soviet open-hearth equipment, and produce export-quality steel. Advanced plants employed more engineers and high-skilled technicians, established professional schools, and their counties had 10.4 percent higher STEM university degree rates and 16.8 percent more technical schools.

Scope conditions: results apply to large-scale, capital-intensive state-planned industrial facilities in a country at an early stage of industrialization, under conditions of near-complete trade isolation (1960–1978) that prevented basic plants from compensating via imported foreign capital. The estimated aggregate contribution of the program is that, without both transfer types, Chinese real GDP per capita growth between 1953 and 1978 would have been 7 to 19 percent lower.

Q: What distinguishes the “basic” from the “advanced” Soviet transfer? A: The basic transfer involved duplication of whole Soviet plants through provision of state-of-the-art Soviet machinery, equipment, blueprints, geological surveys, and construction assistance. The advanced transfer added visits of Soviet experts — expected to stay approximately three years — to teach Chinese technicians how to operate the machinery and to provide within-firm training in engineering (math, physics, chemistry, organizational and planning methods) and supervisory management based on “scientific management” principles including quality-control methods.

Q: What caused plants to receive different levels of transfer, and why is this variation credible for identification? A: Delays arose from Soviet production capacity constraints (by 1955, one-third of annual Soviet steel-rolling output was destined for China), insufficient experts, translator shortages, and bilateral miscommunication — all documented in historical records as unrelated to project characteristics. When the 1960 Split ended the program, plants’ treatment status was determined by where they happened to be in the delivery queue. ANOVA tests find no significant differences in approval year, investment, workforce, equipment value, project length, or capacity across the three groups, and a multinomial logit on province and industry fixed effects shows no group had higher ex-ante probability of receiving either transfer type.

Q: What were the output effects of the basic transfer, and why did they fade? A: Output of basic plants was not significantly above comparison plants for the first two years, peaked at 14.7 percent higher six years after receiving Soviet machinery, then declined monotonically and became statistically insignificant after 20 years. This timing corresponds to the estimated 15-year life cycle of Soviet capital goods. TFPQ of basic plants followed the same pattern, peaking at 14.5 percent above comparison plants. Without the know-how component, basic plants could not develop new processes or home-fabricate replacement capital, so productivity advantages disappeared as Soviet equipment became obsolete.

Q: What were the output and productivity effects of the advanced transfer? A: Advanced plants’ output rose 8.4 percent relative to basic plants within two years of the Soviet transfer and 19.7 percent within 20 years, reaching a cumulative effect of 49.5 percent after 40 years. TFPQ of advanced plants increased from 8.3 percent above basic plants two years after the transfer to 47.9 percent after 40 years. These effects were driven by output growth rather than differential input use — the number of workers, coke, and iron were statistically indistinguishable across the three plant types — ruling out government input reallocation as an explanation.

Q: Did the advanced transfer affect steel quality? A: Advanced plants produced substantially more crude steel (higher quality, lower carbon content) and less pig iron than basic and comparison plants, and this quality advantage persisted well beyond the 20-year life cycle of Soviet capital. Basic plants also shifted toward crude steel initially but the quality advantage dissipated once Soviet machinery became obsolete, whereas advanced plants maintained the shift through adoption of the basic oxygen process and later continuous casting furnaces.

Q: What is the main mechanism through which the advanced transfer generated persistent effects? A: The advanced transfer equipped engineers and supervisors with organizational, technological, and planning knowledge, enabling advanced plants to develop and adopt the basic oxygen steelmaking process independently during China’s 1960–1978 period of trade isolation. Advanced plants had a 15.2 percent higher probability of using the basic oxygen process five years after the transfer and a 65.1 percent higher probability twenty years after, relative to basic plants. They also home-fabricated continuous casting furnaces, making them 26.7 to 78.4 percent more likely to use such furnaces 10 to 20 years after the transfer; basic plants showed no differential advantage over comparison plants on this measure.

Q: What role did trade openness play in the divergence between basic and advanced plants? A: Once China opened to international trade from 1978, advanced plants relied dramatically less on imported foreign capital than basic plants — likely because they had developed domestic production capabilities. At the same time, advanced plants exported 45.5 percent more steel and produced 51.1 percent more steel above international quality standards than basic plants. Basic plants showed no differential imports of foreign capital or differential exports relative to comparison plants, suggesting that once both types could access foreign machinery, basic plants lost any remaining productivity edge.

Q: What were the human capital effects of the advanced transfer? A: Over time, advanced plants opened training schools for high-skilled technicians and offered within-firm training programs for engineers. As a result, advanced plants employed more engineers and high-skilled technicians and fewer low-skilled workers than basic plants, while the human capital composition did not differentially change between basic and comparison plants. At the county level, universities hosting advanced plants were 10.4 percent more likely to offer STEM degrees, had 16.8 percent more technical schools, 14.3 percent more STEM college graduates, and 17.6 percent more high-skilled workers than counties hosting basic plants.

Q: Did the government differentially favor basic or advanced plants after the Split? A: The paper finds no evidence of special government favor. Government transfers and loans were not differentially allocated to basic or advanced plants in either the short or long run. Distance from railroads and roads did not change differentially across plant types. Measures of political connection and politician quality at the prefecture level showed no significant differences across the three groups in the 40 years after the Soviet transfer. County-level total investment and investments in related and unrelated industries were also statistically indistinguishable.

Q: What were the intra-firm spillover effects? A: Steel plants in the same firm as advanced plants increased their steel production by 24.9 percent and were 22.1 percent more productive relative to plants in the same firm as basic plants, after the Soviet transfer. Plants in the same firm as basic plants showed no differential performance relative to plants in the same firm as comparison plants. The within-firm spillovers appear driven by the transmission of new technologies and production methods through formal within-firm training programs, as supported by historical records.

Q: What were the horizontal spillover effects across firms? A: Steel plants in the same counties as advanced plants produced 12.9 percent higher output and were 12.4 percent more productive than those in counties hosting basic plants, after the transfer. They were more likely to adopt basic oxygen converters and continuous casting furnaces, and from 1978 they exported significantly more and produced more steel above international quality standards, mirroring the patterns of the advanced plants themselves.

Q: What were the vertical spillover effects? A: Steel plants in counties hosting nonsteel basic plants produced 14.2 percent more steel than those in counties hosting nonsteel comparison plants, suggesting some output spillover from basic machinery. However, only plants in counties of advanced nonsteel plants experienced a productivity increase — estimated at 16.4 percent — relative to plants in counties of basic nonsteel plants. These supply-chain firms were also the only ones to show increased adoption of basic oxygen and continuous casting furnace technology and differential engagement in trade.

Q: How did market liberalization reforms interact with the spillover effects? A: Starting in the late 1990s, privatized firms economically related to advanced plants outperformed their counterparts in terms of value added, TFPR, and exports, while state-owned firms in the same counties no longer showed a competitive advantage. New private firms locating in counties that had hosted advanced plants received an additional performance gain. At the county level, counties hosting advanced plants had on average 16.6 percent more private firms and 25.2 percent more privately-produced industrial output than counties hosting basic plants. The mechanism appears to be the stock of industry-specific human capital concentrated in those counties, which private firms could draw on once allowed to compete for workers.

Q: What is the estimated aggregate contribution of the Soviet transfer to Chinese growth? A: Province-level regressions show that each additional basic project increased province-level output by 1.1 percent per year on average, and each additional advanced project by 6.2 percent per year. A back-of-the-envelope calculation implies that without both transfer types, Chinese real GDP per capita growth between 1953 and 1978 would have been 7 to 19 percent lower.

Q: How does the paper rule out selection on unobservable characteristics? A: Using the Oster (2019) methodology, the paper finds that for the treatment effects to become statistically insignificant, selection on unobserved variables would need to be 8 to 19 times larger than selection on observed variables — a range the authors characterize as implausible given the strong balancing on observables and the historical documentation of delay causes.

Q: How does this paper differ from Heblich et al. (2020), which also studies Sino-Soviet technology transfer? A: Heblich et al. (2020) study long-run negative spillovers of the 156 Projects on counties that hosted them relative to counties that were geographically suitable but ultimately not selected, focusing on an outside-the-program comparison. This paper instead exploits within-program variation — differences across the three plant types — using plant-level data to assess short-, medium-, and long-run direct effects and spillover effects of different transfer intensities.

Basic Transfer: The provision of Soviet state-of-the-art machinery, equipment, blueprints, geological surveys, and plant construction assistance — duplicating a whole Soviet plant — without accompanying human capital or organizational training.

Advanced Transfer: The full Soviet technology and know-how package: basic machinery provision plus multi-year visits of Soviet experts who taught Chinese engineers and production supervisors organizational, technological, and planning methods based on “scientific management” principles.

Comparison Plants: Plants approved under the 156 Projects that received neither Soviet machinery nor technical assistance due to delays compounded by the Split, and which continued operating with traditional domestic technology.

156 Projects: An array of 139 approved, technologically advanced, large-scale, capital-intensive industrial facilities whose construction the Soviet Union agreed to support between 1950 and 1957 as part of the Sino-Soviet Alliance, representing 45.7% of Chinese GDP in 1949.

Tacit Knowledge: Industry- and firm-specific knowledge embodied in workers and organizations — including operational methods, quality-control procedures, and process innovation capabilities — that cannot be transferred through capital goods alone and requires extensive on-the-job training from foreign experts.

Basic Oxygen Process: A steelmaking process innovation that became predominant in the 1960s by blowing oxygen through molten pig iron to reduce carbon content; adopted by advanced plants through endogenous process development, while basic plants showed no differential adoption relative to comparison plants.

Source Text Origin: The paper’s classification scheme for the grounding of evidence — in this case, full working paper text obtained from NBER WP 29455, enabling comprehensive summary of quantitative results, mechanisms, and robustness tests.

Why Doesn't the United States Have National Health Insurance?

Mon, 01 Jan 0001 00:00:00 +0000

This paper investigates a critical juncture in the development of national health insurance (NHI) in the United States: the post-World War II period when most peer nations moved to establish comprehensive public coverage while the U.S. did not. The authors examine the causal role of the American Medical Association (AMA), which in 1949 hired Whitaker & Baxter’s Campaigns, Inc. — the country’s first political public relations firm — to direct a nationwide campaign opposing NHI and promoting private (voluntary) health insurance (PHI).

The Campaign had two main components. First, a physician outreach component in which AMA members distributed pamphlets to patients warning against “socialized medicine” and encouraging enrollment in private plans, and acted as liaisons to local civic organizations to solicit resolutions against NHI sent to elected officials (nearly 50 million pieces of material were sent to physicians). Second, a mass newspaper advertising component, in which a standard ad was placed across newspapers nationwide, with an additional $19 million (approximately $240 million in current dollars) in coordinated tie-in advertising from roughly 23,000 corporations and industry associations. The messaging framed NHI as “un-American” and associated private insurance with “freedom” and “the American way,” providing little substantive information about insurance products.

The authors construct novel measures of Campaign exposure by combining (a) per capita pamphlets distributed by AMA physicians and (b) per capita advertising circulation scaled by local newspaper readership, using archival data from the Whitaker & Baxter Archives (Sacramento), the National Archives (Washington D.C.), digitized AMA Medical Directories, the N.W. Ayer & Son’s Newspaper Directory, and newly discovered Blue Shield enrollment data from AMA Council on Medical Service annual reports covering 1946–1954.

The primary estimation strategy exploits spatial variation in Campaign intensity combined with its timing, using event studies with state and year fixed effects and design controls for income per capita and unionization. The identifying assumption — that Campaign intensity was conditionally as-good-as-randomly assigned — is supported by balance tests showing no pre-Campaign correlation between exposure and enrollment or sociodemographic characteristics (with the exception of Black population share), and by the historical record that the Campaign was organized hastily following Truman’s unexpected 1948 electoral victory.

Main findings: A one standard deviation increase in Campaign exposure explains approximately 20% of the post-Campaign increase in PHI enrollment, corresponding to roughly 14 million additional enrollees — an effect comparable in magnitude to increasing average per capita income by approximately $100 (about 7 percent). On public opinion, a one standard deviation increase in Campaign exposure led to a six percentage point decline in popular support for NHI per Gallup survey wave, a reversal occurring against a backdrop of 69% pre-Campaign approval that was trending upward. For context, this six-point magnitude approximates the entire gap in NHI support between union and non-union households, or one-third the racial gap in support. Campaign intensity also predicts civic organizations passing resolutions favoring PHI, Republican legislators adopting speech semantically similar to Campaign propaganda, and — by 1952 — AMA members being five times more likely to donate to the Eisenhower-Nixon ticket than non-AMA physicians, with donation rates increasing in Campaign intensity.

Scope conditions: The analysis covers 48 U.S. states from 1946 to 1954, ending at the 1954 IRS tax code change that expanded commercial insurers’ market share. The enrollment data capture Blue Shield (physician-run) plans specifically; the paper explicitly notes that commercial insurer granular data are unavailable for the main Campaign period. The authors argue that multiple subsequent factors — middle-class acquisition of private coverage reducing demand for a public option, incumbent interests defending the status quo, and the persistent ideological linkage of private insurance with freedom — help explain why NHI was not adopted in subsequent decades, though these persistence mechanisms are outside the paper’s direct empirical scope.

Q: What was the AMA’s Campaign, and what prompted it? A: In response to Harry Truman’s unexpected 1948 presidential victory alongside a Democratic Congress — and with a majority of informed voters favoring NHI — the AMA hired Whitaker & Baxter’s Campaigns, Inc. to run the National Education Campaign (NEC). The Campaign had two components: physician outreach (pamphlet distribution to patients, liaison to civic organizations) and mass newspaper advertising. The AMA paid Whitaker & Baxter approximately $1.2 million per year in current terms, and coordinated an additional $19 million in 1950 dollars (roughly $240 million today) in tie-in advertising from allied corporations and trade groups.

Q: How is Campaign exposure measured, and how is it validated as conditionally exogenous? A: Campaign exposure combines two standardized components: per capita pamphlets distributed by AMA physicians (pamphlet quantity from W&B archives scaled by state AMA membership share) and per capita advertising circulation scaled by local newspaper readership (share of adults with more than five years of schooling). The two components are summed and standardized. Exogeneity is supported by balance tables showing no pre-Campaign correlation between exposure and enrollment or Gallup opinion, by the absence of discontinuous changes in income or unionization at Campaign onset, and by the historical fact that Campaign logistics relied on pre-existing networks assembled hastily in response to Truman’s unanticipated victory.

Q: What is the main effect of the Campaign on private health insurance enrollment? A: A one standard deviation increase in Campaign exposure is associated with a two percentage point increase in the share enrolled in PHI in the preferred specification (Column 4 of Table 1, which includes income, unionization, state fixed effects, and year fixed effects; coefficient 0.020, se 0.007, significant at 1%). This accounts for approximately 20% of the overall post-Campaign increase in PHI enrollment, corresponding to roughly 14 million new enrollees. The pre-Campaign coefficient is not statistically significant (coefficient 0.004, se 0.005), and the F-test p-value for pre-trends is 0.958.

Q: What is the effect of the Campaign on public opinion toward NHI? A: Using Gallup survey data, a one standard deviation increase in Campaign exposure led to an approximately six percentage point decline in individual support for NHI legislation per survey wave, against a pre-Campaign approval level of 69% that was trending upward. The F-test p-value for pre-trends in the Gallup event study is 0.179. This six-point effect is approximately equal to the gap in NHI support between union and non-union households, and approximately one-third the racial gap in support.

Q: What evidence links the Campaign to civic organizations and the legislative process? A: The Campaign’s archives document all civic organizations “on record against compulsory health insurance,” meaning they had passed resolutions in favor of PHI. The authors find a positive relationship between Campaign intensity and civic organizations passing such resolutions at the county level. Resolutions sent to elected officials were traced to the Congressional Record and to physical folders in the National Archives; their semantic similarity to AMA-WB propaganda is confirmed. Republican legislators’ speech in the 81st Congress shows increased similarity to Campaign language in proportion to Campaign intensity in their district or state, while Democrat legislators do not show this pattern. NHI and the AMA experienced spikes in mention frequency in the Congressional Record during this period.

Q: Did the Campaign affect physician political behavior beyond the clinic? A: By 1952, when the Republican platform had fully adopted the AMA’s position, AMA members were approximately five times more likely to donate to the Eisenhower-Nixon ticket than non-AMA physicians, with donation probability increasing in Campaign intensity. The authors digitized the donor list from the National Professional Committee for Eisenhower (NPCE) — a separate lobbying entity created because the AMA legally could not endorse candidates — and linked approximately 80% of physician donors to the AMA Medical Directory.

Q: What alternative explanations for PHI growth does the paper address, and how? A: The standard literature attributes PHI growth to the 1942 Stabilization Act wage freeze (which left benefits unconstrained), collective bargaining rights clarified in the late 1940s, and the 1954 IRS tax exemption for employer-paid premiums. The authors include income per capita and unionization as core design controls and show that their Campaign exposure coefficient is stable across specifications with and without these controls (coefficients of 0.025 and 0.020 in Table 1 Columns 1–2 vs. 3–4, respectively). The analysis stops in 1954 before the tax change, and the authors note that by 1952 roughly 63% of households already had some form of medical expense insurance.

Q: What is the conceptual mechanism through which the Campaign operated? A: The authors adapt Sobbrio (2011)’s indirect lobbying model. Voters hold uniform priors over whether NHI enactment yields net positive or negative social surplus. The private-sector advocate (AMA-WB) sends messages that shift voters’ posterior beliefs toward the negative-surplus state and, simultaneously, encourage PHI enrollment, which reduces voters’ private valuation of a public option. Because citizens were likely unaware of the coordinated tie-in advertising across industries and the financial motivation behind physician messaging, the framing operated through naive belief updating. The public-sector advocate (Truman administration, Committee for the Nation’s Health) was vastly outresourced — the CNH raised only $104,000 in 1949 — and faced legal constraints on executive lobbying.

Q: What advertising tactics specifically characterized the Campaign, and what do they imply about mechanisms? A: Campaign pamphlets and ads provided little or no substantive information about insurance products (coverage, eligibility, cost) and instead tied health insurance to ideological symbols: “freedom,” “the American way,” “the voluntary way,” and warnings about “socialized medicine.” Word clouds from Campaign materials confirm “America” and “freedom” as dominant terms. The authors connect this to behavioral models of advertising (Mullainathan, Schwartzstein and Shleifer 2008) whereby advertisers create or exploit associations to influence product beliefs. The absence of informational content is consistent with effects operating through ideology and identity rather than rational product evaluation.

Q: What explains why the U.S. did not adopt NHI in subsequent decades after the immediate Campaign period? A: The authors offer three mechanisms (discussed outside their main empirical scope): First, as middle-class Americans obtained PHI through employers, demand for a public option diminished — the model formalizes this as reduced private valuation of NHI. Second, incumbents who benefit from the private status quo — Blue Cross Blue Shield, AMA, American Hospital Association, and pharmaceutical companies, which today comprise four of the top ten direct federal lobbyists — actively work to maintain it (Acemoglu, Egorov and Sonin 2021). Third, the Campaign’s ideological framing proved durable: ideologically similar rhetoric opposing “socialized medicine” appeared in campaigns against both Clinton-era and Obama-era reform efforts, and has been linked to increased adverse selection and preventable deaths (Bursztyn et al. 2022; Galvani et al. 2022).

Q: What are the paper’s main contributions to the literature? A: The paper provides the first causal evidence on the AMA’s political role in blocking NHI at the post-WWII juncture, contributing to the economic history of U.S. social insurance development. It contributes to the advertising literature by providing credible estimates of a sustained national campaign combining trusted field agents (physicians) with mass media, and to the lobbying literature by documenting indirect lobbying — persuasion of ordinary citizens — as a distinct and effective tool alongside direct lobbying. It also documents physician behavior outside the clinical setting, showing how rents from supply-side constraints were deployed to shape the market for medical services.

Indirect lobbying: In the paper’s usage, persuasion of ordinary citizens via campaigns — as distinct from direct lobbying of policymakers — used to shift median voter beliefs and behavior to achieve legislative goals. Whitaker & Baxter are credited with creating this field through their work at Campaigns, Inc.

Campaign exposure: The paper’s composite treatment variable, constructed as the sum of two standardized components: per capita pamphlets distributed by AMA physicians (physician outreach) and per capita advertising circulation scaled by local newspaper readership (mass communications), then re-standardized to mean 0, standard deviation 1.

Tie-in advertising: Coordinated newspaper advertisements by third-party corporations and trade associations placed simultaneously with the main AMA-WB Campaign ad, sharing the “Voluntary Way is the American Way” slogan. Approximately 60% of newspapers with a main Campaign ad also had tie-in ads, averaging three per issue; third-party spending totaled approximately $19 million in 1950 dollars (~$240 million current).

Voluntary (private) health insurance: In the paper’s framing, the AMA-promoted alternative to NHI — prepaid medical service plans run by state medical societies (Blue Shield) or nonprofit hospitals (Blue Cross) — deliberately labeled “voluntary” to contrast with “compulsory” NHI, embedding the product within an ideological frame of free choice.

National Education Campaign (NEC): The AMA’s official name for the anti-NHI campaign directed by Whitaker & Baxter starting in 1949, characterized as “educational” to provide legal cover; the name itself illustrates the indirect lobbying strategy of framing political advocacy as public information.

Source text origin / abstract-only block: Not a paper-defined concept; excluded.

Naive voter updating: The paper’s modeling assumption (drawn from Sobbrio 2011) that voters held uniform priors on health insurance policy outcomes and updated beliefs via Bayesian message receipt, without awareness of coordination across industries or the financial motivation of physician messengers — making the ideological framing effective.

Physician field agents: In the Campaign’s design, AMA member physicians served as credible, trusted intermediaries who distributed pamphlets to patients and solicited civic organization resolutions, leveraging their social status to amplify the Campaign’s reach into communities where mass advertising alone would be insufficient.