Hi David,

Productivity is simply some measure of aggregate output over aggregate input. in the single input-single output case this is simply Q/X. When using multiple inputs or outputs you usually need price information for the respective series and to construct indices of aggregate input and output.

Efficiency on the other hand is a relative concept. Efficiency is normally measured relative to some basis within a given time period - usually the most 'efficient' firm (that with the highest aggregate input to aggregate output ratio).

In most quantitative studies considering both of these you usually use some method to first estimate the production frontier in each time period of your sample (if a panel of data). You can then obtain efficiency scores in each period and calculate a range of alternative decompositions - the ones i am most familiar with are based on O'Donnell and other authors (see below). Then it is simply a matter of considering changes across time for each of the components of TFP - usually something like (1) technological change; (2) technical efficiency; (3) scale efficiency. If you have good price data you can also do decomposition of profitability into TFP (and it's parts) and terms of trade. I have a paper which does the first one of these in my profile i think - it might give some idea of how and what you can do. Alternatively go to: http://ideas.repec.org/p/qld/uqcepa/70.html for a copy of O'Donnell's decomposition methodology.

I do doubt, if you read decent articles from for the journal of productivity analysis, that you would find people mixing up the concepts of productivity and efficiency.

Hope that helps. As always happy to be corrected on anything, just woken up so could be a bit fuzzy still.

-Daniel

Thanks a lot Daniel for the wonderful opinion shared. Your point is well noted and very much appreciated.

One of the most important properties of an ecosystem is its productivity, which is a measure of the rate of incorporation of energy by plants per unit area per unit time. Normally ecologists compare ecological productivity with total annual plant growth and biomass in a particular ecosystem. So it can also be related to the organic fertility of the respective area.

The cycle of ecological productivity starts with a process known as photosynthesis, where plants absorb carbon dioxide in the presence of sun light and produce their food (biomass). Ecological productivity is also measured with respect to production efficiency in an ecosystem.

Productivity = Outputs / Inputs

The other factors which influence ecological productivity are rainfall, temperature, humidity, altitude, light intensity etc.

Ecological efficiency describes the efficiency with which energy is transferred from one trophic level (a particular position occupied by a group of organisms in a food chain:primary producer, primary consumer, secondary consumer, or tertiary consumer) to the next. It is determined by a combination of efficiencies relating to organismic resource acquisition and assimilation in an ecosystem. Large amounts of energy are lost from the ecosystem between one trophic level and the next level as energy flows from the primary producers through the various trophic levels of consumers and decomposers. The main reason for this loss is the second law of thermodynamics, which states that whenever energy is converted from one form to another, there is a tendency toward disorder (entropy) in the system. In biologic systems, this means a great deal of energy is lost as metabolic heat when the organisms from one trophic level are consumed by the next level.

Production efficiency is calculated as the ratio of net primary production to gross primary production.

Efficiency = [100% * (actual output / standard output)]

Energy transfer between trophic levels is generally inefficient, such that net production at one trophic level is generally only 10% of the net production at the preceding trophic level (the Ten percent law, first formulated by Raymond Lindeman). Due to non-predatory death, egestion, and respiration, a significant amount of energy is lost to the environment instead of being absorbed for production by consumers. The figure approximates the fraction of energy available after each stage of energy loss in a typical ecosystem, although these fractions vary greatly from ecosystem to ecosystem and from trophic level to trophic level. The loss of energy by a factor of one half from each of the steps of non-predatory death, defecation, and respiration is typical of many living systems. Thus, the net production at one trophic level is or approximately ten percent that of the trophic level before it.

Fantastic and detailed...thanks a lot Morales for the wonderful and brilliant opinion shared. Your suggestion is well noted and very much appreciated

Dear David. My modest contribution is in fact a summary of the opinions of some experts in the important field.

I am glad to know that my modest contribution could help to understand these two important concepts.

See: http://smallbusiness.chron.com/productivity-versus-efficiency-66229.html

Thanks a lot Hussein for the link

https://www.eolss.net/sample-chapters/C10/E5-15A-00-00.pdf

It is very difficult to establish precise measures for the sustainable development process. Sustainable economic development in correlation with ecology should be measured to determine if it is being implemented. It is necessary to define precise determinants that on one hand will determine the pace of economic development and on the other hand will take into account specific issues of ecology. It should be a set of quantified indicators based on selected measurable and quantitative data, so that the whole analytical process can be considered as a research objective method. The best solution will therefore be to develop an analytical scoring method, for which the basic components of this method will be defined economic and ecological quantitative indicators.

In view of the above, the current question is: How to define precise measurable factors for the process of sustainable economic and ecological development?

Thanks a lot for your answers.