4.2 Market Size in Innovation: Theory and Evidence From the Pharmaceutical Industry
42 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

According to the provided text, what is the relationship between market size and entry for generic drugs?

  • Generic drug entry is equally responsive to changes in market size as non-generic drug entry.
  • Generic drug entry is less responsive to changes in market size than non-generic drug entry.
  • Generic drug entry is not responsive to changes in market size.
  • Generic drug entry is more responsive to changes in market size than non-generic drug entry. (correct)

In the context of the model, what is used as a proxy for market size, mj(t)?

  • The number of clinical trials for drug category c at time t.
  • The number of patents for new drugs in category c.
  • Actual market size data for drug line j.
  • Potential market size driven by demographic changes, Mct. (correct)

What does the provided equation log nj(t) = constant + log δj + log mj(t) represent?

  • The relationship between the number of clinical trials and drug approvals.
  • The relationship between generic and non-generic drug market sizes.
  • The relationship between new drug entry and market size when r approaches zero. (correct)
  • The relationship between patents and drug innovation rates.

Which of the following is NOT a direct proxy for innovation rates?

<p>Potential market size (B)</p> Signup and view all the answers

What is a key distinction the study intends to investigate regarding the relationship between market size and drug entry?

<p>Whether there's a difference in the relationship for generic versus non-generic drugs. (A)</p> Signup and view all the answers

Approximately how many non-generic drugs were approved compared to generic drugs in the dataset from 1970-2000?

<p>About half as many non-generics as generics. (A)</p> Signup and view all the answers

How were the 34 drug approval categories grouped for analysis?

<p>By the age group that accounted for the largest fraction of use in that category. (B)</p> Signup and view all the answers

What trend was observed when comparing the income share and drug approvals for the 0-20 age group?

<p>Both income share and drug approvals showed a downward trend. (C)</p> Signup and view all the answers

What is the stated reason for fluctuations in the total number of drug approvals?

<p>A number of institutional changes, including discovery of corrupt FDA officials. (D)</p> Signup and view all the answers

What happened to the drug approval process for generics in the early 1990s?

<p>It was greatly slowed down. (A)</p> Signup and view all the answers

What was the implication of finding positive association between contemporaneous changes in population share and changes in drug approvals for corresponding age groups?

<p>Drug approvals are linked to the corresponding segment of the population. (D)</p> Signup and view all the answers

What statistical methods were used for analysis, according to the passage?

<p>Non-linear least-squares (NLLS) and ordinary least-squares (OLS). (B)</p> Signup and view all the answers

What does the text suggest about the drug entry and income shares for the 30-50 age group?

<p>Both the shares of income and drug entry increased. (D)</p> Signup and view all the answers

According to the model, what condition must be met for steady-state equilibrium regarding R&D level?

<p>The R&amp;D level must be constant, i.e., $ż_j(t) = 0$. (D)</p> Signup and view all the answers

In the steady state, which of the following factors would lead to an increase in R&D for a given drug line?

<p>A decrease in interest rates (B)</p> Signup and view all the answers

In this extended model, how does the equilibrium behavior of R&D for a specific drug line relate to other drug lines?

<p>It is completely independent of research and profitability in other drug lines. (C)</p> Signup and view all the answers

What conclusion can be drawn about the dynamics of $z_j(t)$ based on the provided analysis?

<p>Starting away from the steady-state, the equilibrium $z_j(t)$ will immediately jump to its steady-state value. (B)</p> Signup and view all the answers

Consider a scenario where a future increase in market size $Y_j$ is announced at time $t_0$ for a future date $t̂ > t_0$. According to the model, what happens to $z_j(t)$ at $t_0$?

<p>$z_j(t)$ will smoothly increases towards the new steady-state equilibrium starting at $t_0$. (A)</p> Signup and view all the answers

If a future market size is expected to increase, what occurs with the value $V_j(t|q_j)$ before the change in market size is realized?

<p>$V̇_j(t|q_j)$ becomes less than 0. (D)</p> Signup and view all the answers

What is the implication of the fact that the right hand side of equation (15) is strictly increasing in $z_j(t)$ at $z_j(t)=z^S_j$?

<p>It implies that there can be at most one intersection with the 0 axis, and at this intersection point, $ż_j(t)/z_j(t)$ is increasing in $z_j(t)$. (D)</p> Signup and view all the answers

In the provided model, what does the term $M_{ct}$ represent?

<p>The potential market size for category c at time t. (B)</p> Signup and view all the answers

In the given model when it is said that there are no transitional dynamics, what does this imply regarding R&D?

<p>The R&amp;D level immediately jumps to its new steady-state value when there is a change. (C)</p> Signup and view all the answers

What is the primary reason for using the logarithm of $N_{ct}$ as the dependent variable?

<p>To ensure that drug category and time effects have proportional impacts. (D)</p> Signup and view all the answers

Why is the original model (equation 23) problematic when $N_{ct}$ equals 0?

<p>The logarithm of $N_{ct}$ would be undefined, making estimation impossible. (B)</p> Signup and view all the answers

In equation (24), how is $Ñ_{ct}$ transformed for cases where $N_{ct}$ = 0?

<p>$Ñ_{ct}$ is set to 1 when $N_{ct}$ = 0. (B)</p> Signup and view all the answers

What is the potential drawback of introducing the dummy variable $d_{ct}$ in equation (24)?

<p>It introduces statistical bias because $d_{ct}$ is a function of $N_{ct}$. (A)</p> Signup and view all the answers

According to the provided equations, what is the impact on $z_j(t)$ if $\delta_j$ increases, assuming that Assumption (19) holds?

<p>$z_j(t)$ decreases (D)</p> Signup and view all the answers

Based on the model, what happens to R&D, represented by $z_j(t)$, if Assumption (19) is not valid?

<p>R&amp;D, $z_j(t)$, becomes zero. (A)</p> Signup and view all the answers

According to the model, the entry rate of non-generics, $n_j(t)$, is influenced by which of the following factors?

<p>Both the parameters $\mu$ and $\theta_j$ (A)</p> Signup and view all the answers

What does the model predict about the relationship between market size and the entry rates of both non-generics, $n_j(t)$, and generics, $g_j(t)$?

<p>Both entry rates respond positively to market size (A)</p> Signup and view all the answers

In the context of the model, if $\mu = 0$, what is the state of the equilibrium?

<p>The equilibrium is that of Proposition 1 (D)</p> Signup and view all the answers

According to the model, what factor determines whether the entry of generics or non-generics will respond more to changes in market size, $Y_j(t)$?

<p>Whether $\mu$ is larger than $(\delta_j - \mu \theta_j) / (\theta_j - \delta_j)$ (A)</p> Signup and view all the answers

What happens to the limiting value of $h_j(t)$, which represents a measure of product quality, as $t$ approaches infinity, given that there is no R&D?

<p>It approaches zero (D)</p> Signup and view all the answers

In the model, what is the relationship between the entry rate of non-generics, $n_j(t)$, and the parameter $\delta_j$?

<p>The entry rate is not affected by $\delta_j$ (A)</p> Signup and view all the answers

What does the use of maximum likelihood standard error compared to the robust standard error indicate in the context of the given study?

<p>The maximum likelihood standard error assumes a Poisson structure, while the robust standard error does not. (B)</p> Signup and view all the answers

How does using income and expenditure to compute market size affect estimates, compared to estimates based on a different methodology?

<p>It tends to produce larger estimates compared to the estimates derived from alternative methods in the studied tables. (B)</p> Signup and view all the answers

What is the primary distinction between panels A and B in Table 3B, regarding estimation procedures?

<p>Panel A uses maximum likelihood with no weights, while panel B uses a weighted maximum likelihood approach. (A)</p> Signup and view all the answers

What does the negative binomial model account for that the standard Poisson model does not?

<p>It accounts for overdispersion of the Poisson parameter. (A)</p> Signup and view all the answers

What effect does using demographic information from multiple regions have on the study's market size measure?

<p>It produces results that are similar to those using U.S. information alone, with no significant differences. (C)</p> Signup and view all the answers

If a potential market size measure based on the NAMCS data produces similar weighted and unweighted results, what does this suggest?

<p>The distribution of the observations is more even across categories. (A)</p> Signup and view all the answers

In the context provided, what does the term 'overdispersion' refer to?

<p>A situation where the variance of a dataset is larger than its mean. (A)</p> Signup and view all the answers

What is the main advantage of using a robust standard error over maximum likelihood standard error?

<p>Robust standard errors are not limited by the assumptions of the chosen model. (C)</p> Signup and view all the answers

Flashcards

Market Size Responsiveness

In economic models, the responsiveness of a variable (like new drug entry) to changes in market size. It measures how much the variable changes for every unit change in market size.

Potential Market Size

A measure of the size of a potential market for drugs, considering factors like population growth and aging, rather than actual sales data.

Logarithmic Model of Drug Entry

Using the logarithm of drug entry (new drug approvals) to estimate the relationship between market size and drug entry.

New Drug Approval Process

The process of getting a new drug approved by the FDA. It includes stages like clinical trials and reviews.

Signup and view all the flashcards

Drug Entry Rate

A quantitative measure of the number of new drugs approved by the FDA in a specific drug category during a specific period.

Signup and view all the flashcards

Steady-State R&D Level (zjS)

In the context of drug development, the steady-state R&D level (zjS) represents the equilibrium point where the rate of change in R&D investment over time (żj) is zero. This means that, in a steady-state, the drug line's R&D investment remains constant.

Signup and view all the flashcards

Factors affecting Steady-State R&D Level

The steady-state R&D level (zjS) is influenced by several factors including the market size (Yj), the research opportunity (δj), and the interest rate (r). A larger market size, greater research opportunities, and lower interest rates all lead to a higher steady-state R&D investment.

Signup and view all the flashcards

Independence of Drug Line R&D

The behavior of R&D investment in one drug line (zj) is independent of the research and profitability of other drug lines. This implies that the R&D decisions for each drug line are made in isolation without considering the influence of other lines.

Signup and view all the flashcards

Instability of Equilibrium and Instantaneous Adjustment

In the model, R&D investment in a drug line (zj) jumps instantaneously to its steady-state level (zjS) when there's a change in market size. There are no gradual adjustments over time. This means that the R&D investment immediately adapts to accommodate the new market condition.

Signup and view all the flashcards

Anticipated Future Changes and R&D

If there's an anticipated future change in market size (e.g., an increase), R&D investment (zj) will start adjusting before the actual change occurs. This is because the anticipation of future changes impacts present R&D decisions. In other words, investors will respond to anticipated changes in market size rather than waiting for the actual change to happen.

Signup and view all the flashcards

Gradual Increase in R&D with Anticipated Changes

The anticipation of a future market size increase leads to a gradual increase in R&D investment (zj) starting from the present moment. This is to ensure a smooth transition towards the new steady-state level when the actual market size increase occurs.

Signup and view all the flashcards

Equilibrium in the pharmaceutical market model

The unique equilibrium in the model where the innovation rate (zj(t)) and entry rate of generics (gj(t)) are determined by market size and the parameters like generic entry cost (δj) and innovation cost (µ).

Signup and view all the flashcards

Entry rate of non-generics (nj(t))

The rate at which new non-generic drugs (original drugs) enter the market, influenced by market size and parameters like generic entry cost (δj) and innovation cost (µ).

Signup and view all the flashcards

Entry rate of generics (gj(t))

The rate at which generic drugs enter the market, influenced by market size and parameters like generic entry cost (δj) and innovation cost (µ).

Signup and view all the flashcards

Positive relationship between entry rates and market size

The model's prediction that the entry rates of both non-generics and generics increase with market size. This aligns with the intuition that larger markets provide greater incentives for entry.

Signup and view all the flashcards

Non-generic entry rate's independence from generic entry cost (δj)

The entry rate of non-generics is not influenced by the generic entry cost (δj), unlike in the baseline model. Instead, it is positively influenced by the innovation cost (µ) and the innovation parameter (θj).

Signup and view all the flashcards

Zero profit condition for generics

The entry rate of non-generics is determined to ensure zero profit for generic producers. This ensures that once generics enter the market, their producers make profits until a new, better drug emerges.

Signup and view all the flashcards

Asymmetric response of non-generics and generics to market size changes

The effect of a change in market size on the entry rate of non-generics or generics depends on the relative magnitudes of the innovation cost (µ) and the ratio of generic entry cost (δj) to innovation parameter (θj). This implies that the response to market changes can be asymmetric between non-generics and generics.

Signup and view all the flashcards

Importance of positive innovation cost (µ) for equilibrium existence

The equilibrium of the pharmaceutical market model relies on the assumption that the innovation cost (µ) is positive. A non-positive innovation cost would lead to an absence of research and development (R&D), resulting in no new drugs entering the market.

Signup and view all the flashcards

New Drug Entry (Nct)

The number of new drugs introduced in a specific category during a particular time period.

Signup and view all the flashcards

Potential Market Size (Mct)

A measure of the market's potential for a drug category, considering factors like population growth and aging.

Signup and view all the flashcards

Control Variables (Xct0)

Variables that control for other factors that might influence drug entry, like economic conditions or regulations.

Signup and view all the flashcards

No Approval Dummy (dct)

The dummy variable used to account for situations where there are no new drug approvals in a category during a specific time period.

Signup and view all the flashcards

Relationship between market size and drug entry

The strength of the relationship between market size and drug entry can vary depending on how precisely we can estimate the age composition of different drug categories.

Signup and view all the flashcards

Steady-State R&D Level

The point where the rate of change in R&D investment over time is zero, suggesting that the drug line's R&D investment is stable.

Signup and view all the flashcards

Poisson Model

A statistical model that assumes a certain distribution of events (like drug approvals) to understand the relationship between variables. It helps analyze the factors influencing drug approvals.

Signup and view all the flashcards

Negative Binomial Model

A statistical model similar to the Poisson model but allows for overdispersion (more variation in events than expected). It's a more flexible model than Poisson to analyze drug approvals.

Signup and view all the flashcards

Non-Linear Least-Squares (NLLS)

An analytical method used to find the best fit for a set of data by minimizing the difference between the model's prediction and the actual data. It helps to estimate the relationship of variables to drug entry.

Signup and view all the flashcards

Study Notes

Market Size in Innovation: Theory and Evidence from the Pharmaceutical Industry

  • This paper examines the effect of market size on new drug entry and pharmaceutical innovation.
  • The study uses U.S. demographic trends to analyze exogenous market size changes.
  • A 1% increase in potential market size for a drug category correlated with a 4-6% increase in new drugs within that category.
  • The increase stems from both generic drug entry and new, non-generic drug entry.
  • The findings remain robust after controlling for various non-profit factors, pre-existing trends, and health care coverage changes.

Theory

  • A basic model links innovation rates to current and future market size.
  • Profit incentives and market size drive innovation, especially in the pharmaceutical industry.
  • Profit driven models and induced/directed technical change models consider profit incentives, market size, and specific innovations.
  • The study uses demographic trends as exogenous market size variations to overcome endogeneity issues inherent in other studies.
  • The analysis considers potential delays in drug development and approval processes.
  • This results suggest delays have no substantial effect but do affect calculations of the timing of R&D and patenting.

Empirical Strategy

  • The paper measures entry and innovation using FDA drug approvals.
  • A 1% increase in potential market size is correlated with an increase in new drug entry by 4-6%.
  • The robustness of the findings is reinforced by checking against lagged drug approvals, trends in biotechnology, insurance coverage, and economic incentives.
  • The study investigates whether current, past, or future market sizes have more impact on drug entry rates; current and short-term future market sizes yielded the strongest results.
  • The paper explores the relationship between market size and drug patents.
  • The analysis incorporates alternative measures of market size, including those based on demographic changes and health insurance coverage.

Generics and Non-Generics

  • The analysis extends to distinguish between generic and non-generic drug entry.
  • Introducing a new generic drug correlates with cost savings and improved availability, impacting market share and revenues.
  • Generic drug entry into an existing market is easier than introducing a fundamentally new drug, with lower required resources.
  • The study investigates whether different responses to market size changes exist between different types of drugs, and concludes that generics have a stronger response than non-generics.

Delays in Development

  • Delays in drug development and approval process are briefly addressed to mitigate potential biases.
  • The model accounts for delays using differential equations and shows that the response to market size is not significantly affected by delays.
  • Anticipation effects on drug entry are explored in a more general setting.

Supply-Side Determinants

  • The robustness of the findings is examined by controlling for non-profit factors, scientific incentives, and government funding (e.g., CRISP data).
  • No significant effects from any of the tested factors are observed on market size impacts.

Patents

  • The paper also examines the effect of market size on patents.
  • The analysis shows that the relationship between patents and market size is weaker and less statistically significant due to potential noise from various factors.
  • Evidence suggests that drug approvals are affected by past and anticipated market size, yet the results are less significant than other considerations.

Conclusion

  • The study finds a substantial and robust positive correlation between market size and new drug approval rates, both for generics and non-generics.
  • The response to market size changes is largely independent of factors like pre-existing trends in R&D, scientific funding sources, and health-related factors.
  • The results have implications for endogenous growth, directed innovations, and health related profit-based innovation incentives.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Description

This study explores the relationship between market size and pharmaceutical innovation, particularly focusing on new drug entries. It reveals that larger potential markets significantly boost the number of new drugs, emphasizing the role of profit incentives. The analysis includes demographic trends to understand variations in market size affecting innovation rates.

More Like This

Diversity and Innovation Quiz
5 questions

Diversity and Innovation Quiz

ReplaceableOrangutan avatar
ReplaceableOrangutan
Biotechnology Entrepreneurship Quiz
8 questions
Use Quizgecko on...
Browser
Browser