Errata
Table of Contents
- Innovation and corporate growth in the evolution of the drug industry
- A New Class of Asymmetric Exponential Power Densities with Applications to Economics and Finance
- Cities and Clusters: Economy-Wide and Sector-Specific Effects in Corporate Location
- Drift criteria for persistence of discrete stochastic processes on the line
I collect here a few mistakes, typically typos in mathematical expressions, that I found in my published papers. Please notify me if in that papers you notice something wrong which is not included here.
Innovation and corporate growth in the evolution of the drug industry
- Authors: G. Bottazzi, G. Dosi, M. Lippi, F. Pammolli, M. Riccaboni
- Journal: International Journal of Industrial Organization
- Date: 2001
- Link: Elsevier
Page 1179, Equation 9: in the denominator the expression \(N-1\) should be replaced with \(N\) to read \[ p_{B.E.}(k) = \frac{ F+N-k-2 \choose N-k }{F+N-1 \choose N } \]
A New Class of Asymmetric Exponential Power Densities with Applications to Economics and Finance
- Authors: G. Bottazzi and A. Secchi
- Journal: Industrial and Corporate Change, 20(4), pp. 991-1030, 2011
- Date: July 4, 2011
- Link: DOI
In Section 2 of this paper something went really bad editing-wise.
Equation 5: the argument of the incomplete Gamma function is wrong. Equation 5 should read \[ F_{AEP}(x;\mathbf{p}) = \frac {a_l \, A_0(b_l)}{C} \; Q(\frac{1}{b_l},\frac{1}{b_l} \, \left|\frac{x-m}{a_l}\right|^{b_l}) \, \theta(m-x) + \left( 1- \frac{a_r \, A_0(b_r)}{C} Q(\frac{1}{b_r},\frac{1}{b_r} \, \left|\frac{x-m}{a_r}\right|^{b_r}) \right) \, \theta(x-m) \]
Equation 6: the expression for the mean is correct. The expression for the variance should read instead \[ \sigma^2_{AEP} = \frac{a_r^3}{C}\, A_2(b_r)+\frac{a_l^3}{C}\, A_2(b_l) - \frac{1}{C^2} \left( a_r^2\,A_1(b_r) - a_l^2\,A_1(b_l) \right)^2 \]
Equation 7: there are several mistakes. The correct formula should read \[ M_h = \sum_{q=0}^h \, {h \choose q} \frac{1}{C^{h-q+1}} \left( a_r^{q+1} \, A_q(b_r) + (-1)^q a_l^{q+1}\, A_q(b_l) \right) \, \left( a_l^2\,A_1(b_l) - a_r^2 \,A_1(b_r) \right)^{h-q} \]
Cities and Clusters: Economy-Wide and Sector-Specific Effects in Corporate Location
- Authors: G. Bottazzi and U. Gragnolati
- Journal: Regional Studies
- Date: 30 Nov 2012
- Link: DOI
Page 10, Equation 12: the subscript "c" of the log function is in fact the name of the function of which the log is computed. The expression should start \[ \log c (\beta, x_l ) = \beta_1 \log POPULATION \ldots \]
Drift criteria for persistence of discrete stochastic processes on the line
- Authors: G. Bottazzi and P. Dindo
- Journal: Journal of Mathematical Economics
- Date: Aug 2022
- Link: DOI
Page 2, in the examples for transient process, parentheses are wrongly placed. In the first bullet point, replace \(P(\lim \sup)_{t \to \infty} x_t=\lim \inf_{t \to \infty} x_t=1\) with \(P(\lim \sup_{t \to \infty} x_t=\lim \inf_{t \to \infty} x_t)=1\); in the second bullet point, replace \(P(\lim \sup)_{t \to \infty} x_t=\lim \inf_{t \to \infty} x_t=0\) with \(P(\lim \sup_{t \to \infty} x_t=\lim \inf_{t \to \infty} x_t)=0\).
Page 3, In the last paragraph of the proof of Theorem 3.1, replace \(P\{\lim_{t \to \infty} X_{T+t} \in I\}>0\) with \(P(\lim_{t \to \infty} X_{T+t} \in I)>0\) and \(P\{x_{T+t+1} \in I \mid x_{T+t+1} \in I \}<1\) with \(P(x_{T+t+1} \in I \mid x_{T+t} \in I )<1\).