Essays on dynamic capabilities: the role of intellectual human capital in firm innovation

Following the dynamic capabilities perspective, I suggest that antecedents to innovation can be found at the individual, firm, and network level. Thus, I challenge two assumptions common in prior research: (1) that significant variance exists at the focal level of analysis, while other levels of analysis are assumed to be homogeneous, and (2) that the focal level of analysis is independent from other levels of analysis. Accordingly, I advance a set of hypotheses to simultaneously assess the direct effects of antecedents at the individual, firm, and network level on innovation output. I then investigate whether a firm s antecedents to innovation lie across different levels. To accomplish this, I propose two competing interaction hypotheses. I juxtapose the hypothesis that the individual, firm, and network-level antecedents to innovation are substitutes versus the proposition that these innovation mechanisms are complements. I test my multi-level theoretical model using an unusually comprehensive and detailed panel dataset that documents the innovation attempts of global pharmaceutical companies within biotechnology over a 22-year time period (1980-2001). I find evidence that the antecedents to innovation lie across different levels of analysis and can have compensating or reinforcing effects on firm-level innovative output.Ph.D.Committee Chair: Frank T. Rothaermel; Committee Member: J. Jeongsik Lee; Committee Member: John Walsh; Committee Member: Luis Martins; Committee Member: Matt Higgin

Interactive stated choice surveys: A study of air travel behaviour

Stated preference (SP) experiments are becoming an increasingly popular survey methodology for investigating air travel choice behaviour. Nevertheless, some evidence suggests that SP experiments do not mirror decisions in real markets. In this paper we introduce a novel survey methodology that aims to make air travel surveys more consistent with real world settings, with the aim of obtaining more realistic results. The survey is modelled on the interface and functionality of an online travel agent (OTA). As with a real OTA, many ticket options are presented. Sort tools allow the options to be reordered, search tools allow options to be removed from consideration, and a further tool allows attributes to be hidden and shown. Extensive use of these tools is made by the 462 respondents, with the captured data revealing some attribute preferences at the individual level, and significant heterogeneity of preference across individuals. A traditional SP component was also completed by the respondents. Our exploratory analysis as well as random utility model estimation results confirm not only that respondents seem to engage more actively with the interactive survey, but also that the resulting data allows for better performance in model estimation. These results have implications for the study of other complex travel choices where interactive surveys may similarly be preferable to standard approaches

Using variograms to detect and attribute hydrological change

There have been many published studies aiming to identify temporal changes in river flow time series, most of which use monotonic trend tests such as the Mann–Kendall test. Although robust to both the distribution of the data and incomplete records, these tests have important limitations and provide no information as to whether a change in variability mirrors a change in magnitude. This study develops a new method for detecting periods of change in a river flow time series, using temporally shifting variograms (TSVs) based on applying variograms to moving windows in a time series and comparing these to the long-term average variogram, which characterises the temporal dependence structure in the river flow time series. Variogram properties in each moving window can also be related to potential meteorological drivers. The method is applied to 91 UK catchments which were chosen to have minimal anthropogenic influences and good quality data between 1980 and 2012 inclusive. Each of the four variogram parameters (range, sill and two measures of semi-variance) characterise different aspects of the river flow regime, and have a different relationship with the precipitation characteristics. Three variogram parameters (the sill and the two measures of semi-variance) are related to variability (either day-to-day or over the time series) and have the largest correlations with indicators describing the magnitude and variability of precipitation. The fourth (the range) is dependent on the relationship between the river flow on successive days and is most correlated with the length of wet and dry periods. Two prominent periods of change were identified: 1995–2001 and 2004–2012. The first period of change is attributed to an increase in the magnitude of rainfall whilst the second period is attributed to an increase in variability of the rainfall. The study demonstrates that variograms have considerable potential for application in the detection and attribution of temporal variability and change in hydrological systems

Search based internet surveys: Airline stated choice

Stated preference (SP) experiments are becoming an increasingly popular survey methodology for investigating air travel choice behaviour. Nevertheless, some evidence suggests that SP experiments do not mirror decisions in real markets. In this paper we introduce a novel survey methodology that aims to make air travel surveys more consistent with real world settings, with the aim of obtaining more realistic results. The survey is modelled on the interface and functionality of an online travel agent (OTA). As with a real OTA, many ticket options are presented. Sort tools allow the options to be reordered, search tools allow options to be removed from consideration, and a further tool allows attributes to be hidden and shown. Extensive use of these tools is made by the 462 respondents, with the captured data revealing some attribute preferences at the individual level, and significant heterogeneity of preference across individuals. A traditional SP component was also completed by the respondents. Mixed multinomial logit models were estimated on data from both the traditional SP and OTA components, with the later exhibiting greater willingness to pay (WTP) heterogeneity

A Comparison of the Genetic Factors Influencing Host Response to Infection with One of Two Isolates of Porcine Reproductive and Respiratory Syndrome Virus

Host genetic differences in viral load (VL) and weight gain (WG) during porcine reproductive and respiratory syndrome virus (PRRSV) challenge were assessed for thirteen trials of ~200 commercial crossbred piglets each, from several different commercial suppliers. Piglets were experimentally infected with PRRSV isolates NVSL-97-7895 (NVSL) or KS-2006-72109 (KS06). VL and WG were moderately heritable and were antagonistically related for both virus isolates. The genetic correlation of host response to NVSL with host response to KS06 was high for both VL and WG. Consistent with previous findings, animals that were heterozygous (AB) for the WUR10000125 (WUR) marker on Chromosome 4 (SSC4) had significantly lower VL than their AA counterparts when infected with either virus isolate; however, a significant increase in WG was only observed when piglets were infected with the NVSL isolate. These results suggest that selecting for increased resistance or reduced susceptibility to PRRSV may be effective across virus isolates. Selecting for the AB genotype for WUR is expected to reduce VL across PRRSV isolates but its effect on WG during infection may differ between virus isolates

Validation of the Effects of a SNP on SSC4 Associated with Viral Load and Weight Gain in Piglets Experimentally Infected with a 2006 PRRS Virus Isolate

Host genetic differences in viral load (VL) and weight gain (WG) during challenge were assessed for five trials of ~200 commercial crossbred piglets each, all from different commercial suppliers. Piglets were experimentally infected with porcine reproductive and respiratory syndrome virus (PRRSV) isolate KS-2006-72109 in order to validate the effects of a SNP previously identified on SSC4 (WUR10000125), whereby AB individuals had increased WG and reduced VL when experimentally infected with PRRSV isolate NVSL-97-7895. VL was defined as the area under the curve of logged viremia from 0-21 dpi. WG was defined as the weight gained from 0-42 dpi. The SNP effects on VL and WG were assessed. AB individuals had higher WG and lower VL than AA individuals, suggesting this marker may be useful for genetic selection of pigs for increased resistance or reduced susceptibility to PRRSV isolates that differ genetically and possibly pathogenically

Factors Associated with N-specific IgG Response in Piglets Experimentally Infected with Porcine Reproductive and Respiratory Syndrome Virus

This study examined serum porcine reproductive and respiratory syndrome virus (PRRSV) N protein-specific IgG levels from sera collected from 464 Large White-Landrace commercial crossbred piglets from three separate experimental infection trials with PRRSV isolate NVSL-97- 7895. IgG levels at 42 days post infection (dpi) were measured by fluorescent microsphere immunoassay, herein referred to as total antibody (tAb) response. tAb levels were assessed for an association with different disease-related traits, the presence of a heritable genetic component, and for genomic regions associated with tAb response. tAb response was negatively associated with viral load (VL) and weight gain from 28-42 dpi (WG) and positively associated with virus rebound (REB) and neutralizing antibody (nAb) levels. Furthermore, tAb response had a heritable genetic component, with a major QTL located on chromosome 7 in the major histocompatibility complex (MHC), whereby heterozygous individuals had a lower tAb response and increased weight gain from 28-42 dpi. These results suggest that genetic selection for tAb response may be useful for selecting for pigs that have increased resistance or reduced susceptibility to PRRSV

Factors Associated with Neutralizing Antibody Response in Piglets Experimentally Infected with Porcine Reproductive and Respiratory Virus

Host genetic differences and other factors associated with neutralizing antibody (NAb) response were examined in 464 Large White-Landrace piglets that were experimentally challenged with porcine reproductive and respiratory virus (PRRSv) isolate NVSL-97-7895. Serum samples and viremia data were collected on piglets periodically for 42 days post infection (dpi). NAb response was defined as the inverse of the highest 1:2 serial dilution of serum without cytopathic effects. Heritability and other factors associated with NAb response were estimated using an animal model in ASReml. These analyses identified two aspects of viremia that were associated with NAb response: viral load (area under the curve from 0-21 dpi) and virus rebound (a two Log increase in viremia after the virus had started to clear). These results also suggested that NAb response may be lowly heritable and provided the groundwork for further characterization of NAb response

Technetium Chemistry in HLW

Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry