The authors find that
when modeling assumptions closely mirror the actual requirements and flexibilities of the final MATS rule, the predicted impact on the electricity sector is less severe.
Not exact matches
Even
when two valuators do agree on the methodology, they may vary on the
assumptions used in that
model and then arrive at very different values for the firm.
When founders discover their
assumptions are wrong, as they inevitably will, the result isn't a crisis, it's a learning event called a pivot — and an opportunity to change the business
model.
And it would not be until they questioned their own most basic
assumptions about «the way Magellan's was managed» — the company's dependence on them, the heroic - leader
model they'd brought into the company from day one — that they would have a shot at doing what few founders can
when the wall confronts them: getting through it.
The problem is
when investors adopt theories and
models that embed the most optimistic
assumptions possible, run contrary to historical evidence, or embed subtle peculiarities that actually drive the results (see, for example, the «novel valuation measures» section of The Diva is Already Singing).
When you say «Copernicanism», are you referring to the heliocentric
model of the solar system — which David's post discussed — or are you referring more broadly to the
assumption that we aren't in an especially privileged position in the universe?
But for my purposes it is enough to say that the
assumptions I have listed have many practical consequences
when governments adopt policies oriented to economic growth on the basis of advice from neoliberal economists, or, indeed, many other economists who share this
model.
When Henry Ford merchandized his
Model T shortly after World War I, advertising was based on the
assumption that the seller and buyer were equally accessible, equally knowledgeable, equally powerful.
Because 2 - D
models make simplified
assumptions about some aspects of the flow, they can't account for changes in the flow, such as
when the flood wave moves around large obstacles, changes rapidly in direction, or fully immerses bridge decks.
How do you judge a
model for the origin of life
when its underlying
assumptions are so uncertain?
The core
assumption that eHarmony makes
when using
models based on data from married couples is that you can generalize their «fit» to data collected from singles.
When we look to test - based evidence — and look no further — to decide whether choice «works,» we are making two rather extraordinary, unquestioned
assumptions: that the sole purpose of schooling is to raise test scores, and that district schools have a place of privilege against which all other
models must justify themselves.
We believe that this
model will allow educators to question their own
assumptions and see opportunities, rather than obstacles,
when shaping their own students» learning experiences.
This double standard re
assumptions works to the benefit of the Passive Indexing
model when it is tested statistically.
Also covered in this section are costs and business
models including
when games have collectible elements or whether they work on the
assumption of expansion
I agree, they should evaluate something... I am not as sanguine as Ray though about how a mismatch «insight» would be employed in the science
when the belief remains that the underlying
assumptions remain robust enough coupled with the scientist as advocate
model you support.
I would argue that if we use a simple radiative
model with a variety of
assumptions, no upper atmosphere cooling but only warming will occur with increased CO2 (see # 333), based on the radiative transfer equations and the Second Law of thermodynamics, but
when other complexities are introduced, this might change.
The problem arises, I believe,
when strong feedbacks, «masking» effects of aerosols and volcanoes and other uncertain
assumptions are fed into computer
models to generate catastrophic scenarios for the near - medium future.
The
assumption of independence leads to increased confidence in the «robustness» of
model results
when multiple
models agree.
There is, however, a point to be made about exercising caution
when evaluating the forward - looking output of a computer
model, particularly
when those
models are used to advocate policy changes on the
assumption that the computer
model accurately simulates the earth's climate, and more particularly
when there is no demonstrable track record of the predictive accuracy of the
model.
So,
when you wrote, «the same mistake that seems to appear in a lot of climate
models, a false
assumption of linearity...» you in fact made the mistake; one of supposing an
assumption where there is instead a demonstration.
Don't be surprised
when they don't question the computer
model assumptions.
Specifically,
when he looked at the climate
models used by the IPCC, Kiehl found they all used very different
assumptions for aerosol cooling and, most significantly, he found that each of these varying
assumptions were exactly what was required to combine with that
model's unique sensitivity
assumptions to reproduce historical temperatures.
When energy
modelling is carried out, the
models contain
assumptions and default values that don't reflect the design.
To be explicit,
when I said «linear
model» I meant the
assumption of validity of linear regression between temperature and independent variables.
When Alarmists say that ENSO's short term effects must balance to zero over the long run they are doing a priori science using the
assumptions of the «radiation - only»
model.
The
assumptions of the global warming
models must be publicly, repeatedly, and systematically critiqued, and
when they do not stand up to scrutiny, these
assumptions and policies must be rejected by the United States government outright.
My personal concern: I was taught that
models are only valid
when their
assumptions hold.
However, its long been apperent that while climate
models and econ
models have similar levels of scientific validity, economists are far more willing to talk about
assumptions their
models make,
when and why those
assumptions might or might not hold, etc., than climate scientists.
Once such an IPCC exposition of the
assumptions, complications and uncertainties of climate
models was constructed and made public, it would immediately have to lead, in my view, to more questions from the informed public such as what does calculating a mean global temperature change mean to individuals who have to deal with local conditions and not a global average and what are the
assumptions, complications and uncertainties that the
models contain
when it comes to determining the detrimental and beneficial effects of a «global» warming in localized areas of the globe.
Quite a remarkable statement
when you consider the myriad
assumptions and uncertainties built into the
modeling scenarios that are needed to favor renewables.
I find it rather disturbing
when models are created based on
assumptions, then tweaked and modified and finally used to run «experiments» which amazingly provide proof of the original belief.
it is well established that warming since 1950 is predominantly anthropogenic» This is is only a
model - derived assertion based on an
assumption of declining natural variability, that was utterly refuted
when the
models were found to have too little natural variation.
When a hypothesis /
model fails the next step is to relook at the hypothesis /
model to see which
assumptions in the
modeling / hypothesis are incorrect.
Regarding the reports on renewable energy standards, Frank Ackerman, a Harvard PhD and Senior Economist with Synapse Energy Economics, Inc. said the Beacon Hill Institute
models contained «wild overstatement (s) of the cost of wind energy, assumed that expensive backup capacity was always needed and running
when wind energy was used, inflated the price of new transmission capacity, and overestimated job losses due to
assumption of «hypersensitivity to tax rates.
A few years ago, Pierce and Adams
modeled the potential cloud forming effect of cosmic rays and found it wanting by more than an order of magnitude, even
when the most favourable
assumptions possible were made.
«The point of the paper is to show a broad range of hypotheticals and use the
model to demonstrate the economic impact, not to read tea leaves and try to precisely forecast future REC prices,» Divounguy said
when asked about the basis for those
assumptions.
When you are this wrong in such a short period something is seriously wrong with your
model and
assumptions.
Simple climate
models are perfect in answering many questions, but they require too many unphysical
assumptions when they are used to answer other questions, and they can not tell anything about some further ones.
Between this shortcut / mistake (which violates the Stephan - Boltzmann equations and was copied by all the following climate scientists) and through the climate
model's
assumption of a constant linear lapse rate of 6C / kilometre
when it is probably not constant), they have changed all the logarithmic radiation equations into linear ones.
The attribution of the warming is made from
assumptions [G and Curry] from
models and the
models are all programmed to input 0.2 degrees rise a decade [the rise that «must «occur
when CO2 is going up at this rate»].»
I personally published what was wrong (with) my own original 1971 cooling hypothesis a few years later
when more data and better
models came along and further analysis showed [anthropogenic global warming] as the much more likely... In fact, for me that is a very proud event — to have discovered with colleagues why our initial
assumptions were unlikely and better ones reversed the conclusions — an early example of scientific skepticism in action in climatology.»
The approach Müller considers «most practical» for adaptation studies is to simply make
assumptions that fall somewhere within the range of
model projections — for example, a 2 - degree temperature rise and 20 % less rain —
when estimating consequences such as shifting crop yields.
The no - brainer part is that
when the
models fail, that is, are unable accurately to predict anything of significance, the investigator should realize that the small signal
assumption has failed.
Matching available past and present observations is a necessary condition, but never can validate a
model because incorrect
assumptions also could fit past data, particularly
when there are many adjustable parameters.
As is typical
when models go wrong, early problems in the
model did not cause users to revisit their
assumptions:
As there are multiple periods in the geological record of tens of millions years in duration
when CO2 levels were high and the planet was cold and
when CO2 levels were low and the planet was warm, it appears there is a basic fundamental
assumption in the
model of atmospheric radiation that is incorrect or there is an omission of another mechanism from the standard
models of atmosphere radiation.
There are numerous
models that show a relationship, but the
models omit more elements of atmospheric complexity than they include (and exclude any solar forcing with the exception of irradiance in some
models), they can not backcast past ca 1900, they can not forecast next month, and they do generate greatly dissimilar forecasts
when fed with the same
assumptions of future conditions.
The former
modeled short - term, natural cooling, not AGW warming, and the latter was very obvious circular reasoning which became redundant
when Hadley later admitted their natural variability
assumptions were wrong anyway.
Some of us simply can not accept as remotely credible a claim to 95 % confidence in distant - future forecasts generated by
models which are inherently incapable of faithfully reproducing the full complexity of the real world climate, particularly
when they rest on elementary
assumptions which are neither proven nor provable.