Comparison of mesozooplankton production estimates from Saanich Inlet (British Columbia, Canada) using the chitobiase and biomass size spectra approaches

Zooplankton production estimates are necessary to understand the availability and transfer of energy to higher trophic levels in marine food webs. Methods have been developed to quantify zooplankton production; however, they are difficult to compare as they focus on single species, groups, stages, or size classes of zooplankton. We compared 2 methods for estimating crustacean production: the chitobiase method (based on a crustacean moulting enzyme), and 3 empirical growth rate models (Huntley-Lopez, Hirst-Lampitt, and Hirst-Bunker) applied to optically resolved mesozooplankton normalized biomass size spectra (NBSS). Mesozooplankton net samples were collected between March and August of 2010 and 2011 in Saanich Inlet (British Columbia, Canada) and analyzed in the laboratory using microscopy and a bench-top laser optical particle counter (lab-LOPC). Microscope and lab-LOPC estimates of abundance and biomass were in close agreement. Crustacean production estimates were highest using Huntley-Lopez (0.20-185.3 mg C m-3 d-1), followed by Hirst-Bunker (0 .01-18.3 mg C m-3 d-1), chitobiase (0.05-15.6 mg C m-3 d-1), and Hirst-Lampitt (0.03-14.3 mg C m-3 d-1). Hirst-Lampitt-, Hirst-Bunker-, and chitobiase-based estimates of crustacean production and trophic transfer efficiency (TTE) yielded similar patterns/magnitude, while the Huntley-Lopez model was more variable. Estimates showed stronger agreement in 2011 than in 2010, attributed to the shift from El Niño to La Niña conditions. We highlight similarities/differences associated with these techniques and suggest that Hirst-Bunker estimates of production and TTE are most consistent with chitobiase-based values.

Testing Growth Theory Using Existing Growth Models for MENA Countries

This paper examines the growing gap between the theoretical and empirical growth literature and policy needs of the developing economies. Growth literature has focused mainly on long term growth outcomes, but policy makers of the developing economies need rapid improvements in the short to medium term growth rates. In this paper we argue that this gap can be reduced by distinguishing between the short to medium term dynamic effects of policies from their long run equilibrium effects. With data from selected 15 MENA countries; we show that an extended version of the Solow (1956) model is well suited for this purpose. We include the education find that the short to medium term growth effects of the investment ratio are quite significant and they may persist for up to 10 years.

GOVERNMENT SPENDING AND ECONOMIC GROWTH RELATIONSHIP: CAN A BETTER INSTITUTIONAL QUALITY FIX THE OUTCOMES?

Empirical growth literature finds conflicting results on the relationship between public spending and long-run economic growth. This paper shows that the nature of relationship between the two variables depends upon the institutional quality of a country. Our empirical investigation relies upon OLS, fixed-effects and system-GMM estimators for a large panel of 113 developed and developing economies during the period 1981–2015. The main findings confirm that the adverse impact of public size on output growth holds only for countries with poor institutional quality. By contrast, when the institutional quality exceeds certain thresholds, the growth inhibiting effects of government size become insignificant. From the fiscal policy viewpoint, these outcomes imply that the productivity of public spending is more important than an excessively large public size of the country.

Sensitivity Analysis of an OLS Multiple Regression Inference with Respect to Possible Linear Endogeneity in the Explanatory Variables, for Both Modest and for Extremely Large Samples

This work describes a versatile and readily-deployable sensitivity analysis of an ordinary least squares (OLS) inference with respect to possible endogeneity in the explanatory variables of the usual k-variate linear multiple regression model. This sensitivity analysis is based on a derivation of the sampling distribution of the OLS parameter estimator, extended to the setting where some, or all, of the explanatory variables are endogenous. In exchange for restricting attention to possible endogeneity which is solely linear in nature—the most typical case—no additional model assumptions must be made, beyond the usual ones for a model with stochastic regressors. The sensitivity analysis quantifies the sensitivity of hypothesis test rejection p-values and/or estimated confidence intervals to such endogeneity, enabling an informed judgment as to whether any selected inference is “robust” versus “fragile.” The usefulness of this sensitivity analysis—as a “screen” for potential endogeneity issues—is illustrated with an example from the empirical growth literature. This example is extended to an extremely large sample, so as to illustrate how this sensitivity analysis can be applied to parameter confidence intervals in the context of massive datasets, as in “big data”.

Effects of Project-Based Learning on Teachers’ Information Teaching Sustainability and Ability

In the context of the Internet for education, informatized teaching has become the most basic and critical ability of teachers. The application of advanced information technology in education means that the improvement in teaching ability requires instructors to better utilize teaching and learning opportunities. Project-based learning is an inquiry-based learning method that embodies learning by doing. With respect to the training of informatization teaching for pre-service teachers, we choose three aspects: information-based instructional design, information-based teaching resource integration, and information-based teaching evaluation, respectively, from PowerPoint (PPT) skills, multimedia courseware production, and micro lectures. This study explores three experimental projects and undertakes detailed empirical growth research on the cultivation of pre-service teachers. We were able to enhance the informatization teaching design ability of pre-service teachers with the training of PPT skills. In this experiment, we found that integration of information-based teaching resources can be improved by the integration of multimedia courseware production. Information teaching evaluation can be improved through micro lecture production. The mechanism provides a more feasible and practical strategy for the training of pre-service teachers in their informatization teaching ability.

The Elusive Determinants of Civil Wars

Like the empirical growth literature, the empirical civil war literature has identified few robust determinants. In this paper, I show that the lack of robust estimates is consistent with rational, forward-looking behavior in a simple dynamic conflict model with asymmetric information. The main result is most of the conflict determinants, such as income per capita, inequality, and natural resource revenues, have ambiguous effects on the conflict risk. The ambiguities largely reflect that, when the parameters change, agents re-optimize.

Productive Specialisation and Growth in the EU15

This paper analyses the relationship between productive specialisation and economic growth in the 15 older European Union member states between 1970 and 2005. The sectoral taxonomy proposed by (Peneder, 2007) is used to classify the different sectors of activity according to the educational levels of the respective workforce and establish a comparison between the manufacturing and the services sector, based on their potential contribution to productivity improvements. The empirical model corresponds to a growth regression where the employment share of the different sectors is the main explanatory variable taken alongside other control variables identified in the empirical growth literature as robust growth determinants and is estimated with the fixed effects method. The results indicate that a higher weight of manufacturing activities that use mostly very low and low educated workers presents a negative association with growth. Services activities that require low educated workers make a negative growth contribution. Manufacturing activities with high and medium-high educational requirements have a positive growth influence, while in the case of services only activities that require highly-educated workers show a positive correlation with growth. The policy advice that can be extrapolated from this study contemplates the design of industrial policies that promote manufacturing activities such as chemicals, telecommunications and transports equipment, and services such as financial intermediation, audit, tax consulting, engineering and legal activities, to promote growth.