Design leads to hypothesis-driven research.

The application of the scientific method is limited to independently observable, measurable events that can be reproduced. The scientific method is also applicable to random events that have statistical distributions. In atomic chemistry, for example, it is impossible to predict when one specific atom will decay and emit radiation, but it is possible to devise theories and formulas to predict when half of the atoms of a large sample will decay. Irreproducible results cannot be studied by the scientific method. There was one day when many car owners reported that the alarm systems of their cars were set off at about the same time without any apparent cause. Automotive engineers were not able to discover the reason because the problem could not be reproduced. They hypothesized that it could have been radio interference from a passing airplane, but they could not prove it one way or another. Mental conceptual experiences cannot be studied by the scientific method either. At this time there is no instrumentation that enables someone to monitor what anybody else conceives in their mind, although it is possible to determine which part of the brain is active during any given task. It is not possible to define experiments to determine objectively which works of art are "great", or whether Picasso was better than Matisse. So-called miracles are also beyond the scientific method. A person has tumors and faces certain death, and then, the tumors start shrinking and the person becomes healthy. What brought about the remission? A change in diet? A change in mental attitude? It is impossible to go back in time to monitor all variables that could have caused the cure, and it would be unethical to plant new tumors into the person to try to reproduce the results for a more careful study.

Formulation of an hypothesis to explain the phenomena.

hypothesis-drivenresearch) involves Observation, Hypothesis, Controlled Experiment and Conclusion.

Identifying variables is necessary before you can make a hypothesis.

Hypotheses, Models, Theories and LawsIn physics and other science disciplines, the words "hypothesis,""model," "theory" and "law" have different connotations in relation to thestage of acceptance or knowledge about a group of phenomena.An hypothesis is a limited statement regarding cause and effect inspecific situations; it also refers to our state of knowledge beforeexperimental work has been performed and perhaps even before new phenomena havebeen predicted.

There is usually one hypothesis for each question you have.

My hypothesisis that many cases of cyclical overheating (temp gauge going up and downrepeatedly while driving at fairly steady speed and incline) are causedby combustion gasses escaping the cylinders into the coolant through aflaw in the head gasket.

In physics, thehypothesis often takes the form of a causal mechanism or a mathematicalrelation.
If the experiments do not bear out the hypothesis, it must berejected or modified.

A hypothesis is an educated guess that must be proved or disproved.

Sauropods seem to have . Until relatively recently, animals as agents of ecosystem change and maintenance was a marginal idea. But today, is thought to be a seminal geophysical event in the Cambrian, and those huge sauropods probably had an ecosystem impact like what elephants have today in Africa. Elephants today break up woods as they feed, as they knock over trees and uproot them. That damage transforms the biome and provides opportunities for other kinds of herbivores and their predators. Elephants also and are considered , which have an outsized impact on their environment. Today, there is a “” to the overkill hypothesis regarding megafauna extinctions soon after humans appeared; such people minimize the impact of humans (their position has an inherent conflict of interest, as those ) and attribute the extinction of elephants of the Western Hemisphere (, ) to climate change and resulting changes in vegetation. If the current situation with African elephants is relevant, it is likelier that those vegetation changes were a of elephant extinction, not a cause. Elephant extinctions would have affected many other kinds of plants and animals, and could have precipitated . Similarly, those huge sauropods would not just have nibbled at vegetation and been relatively harmless browsers, but their vast bulk would have been ideal for pushing over trees to get at their foliage and other devastations of trees in particular, which would have dramatically impacted biomes. Giant dinosaurs probably had keystone species impacts on their environments, particularly the vegetation. Dinosaurs were not the only huge organisms in those days. The appeared in the Jurassic, and would have been immune to dinosaur browsing when they grew large enough. Below is an artist's conception of a typical Jurassic landscape (just as an allosaur and stegosaur are about to cordially interact). (Source: Wikimedia Commons)

At this point, you are ready to translate your questions into hypothesis.

After a hypothesis has been repeatedly tested and …

After newly exposed forest soils have produced a few crops, the yield will decline due to nutrient depletion. When the croplands receive less precipitation, yields drop. When soils wash away due to erosion, crop yields in those eroded soils will decline. Those effects reduce the EROI and surplus energy of farming those lands. When cropland is abandoned due to aridity, nutrient depletion, and erosion, and lands farther from Rome were conquered, deforested, and farmed, it took more energy to transport those crops to Rome than with farms closer to Rome. That also depressed the EROI and surplus energy. When harbors silted up and needed dredging, or were eventually abandoned and a port was built farther away, that also reduced the EROI and surplus energy of Rome-bound food. When food was used to feed soldiers who traveled increasingly vast distances to conquer and plunder peoples and their lands, those would be lower-EROI ventures than conquests closer to Rome. That dynamic has also been called in academic parlance, but in scientific terms, it is really just sucking the dregs of low-EROI resources after high-EROI energy sources have been depleted. Rome’s decline was really just another resource-depletion dynamic. Humanity’s first one was , and Rome only experienced what , , , , and numerous other early civilizations already suffered. Rome just did it on an unprecedented scale.

If the deductions are verified, the hypothesis is provisionally corroborated.

A hypothesis that has been repeatedly disproved is that ..

I hypothesize that exhaust gasses entering the cooling system through abroken head gasket can cause cyclical overheating, unexplained overheating,and coolant loss in the absense of overheat or known leaks.