Aquascope Facts

Collect evidence

All the steps in figure 1 should be present for a scientific investigation to be logically completed. After a general summary, all the different stages are described more precisely with examples.
    The purpose of the procedure is for us to be able to decide if a possible explanation to particular things we see in nature actually is true. An investigation that is performed in a correct way should result in only two things: that we either keep the explanation as possibly correct or reject it as wrong. We can with confidence conclude that the explanation is incorrect when the result from our investigation is what was not predicted in the explanation. This result is expressed in our null hypothesis (see figure 1) and it should include a prediction of results from measurements, since most things in the living world for lots of reasons vary. Consequently the hypothesis states what measured values we should get, if the explanation is correct.
    If the results agree with the null hypothesis it is not as the explanation predicted. In such a case, we keep the null hypothesis and reject the hypothesis and also the model in figure 1. The condition for keeping the model is when what the explanation predicts occurs. If the investigation gives results that agree with the hypothesis it accordingly happened what the explanation predicts. Then we reject the null hypothesis and have support for the model in figure 1.
   Making one turn through this scientific process is not enough, an explanation must constantly be compared with others and subjected to critical examination.

Observations and explanations

We start with observations, which can for example be that a certain alga usually grows on a certain level of the beach. Thereafter we need to formulate an explanation for that observation. Finding explanations to what we have experienced or heard, is something we do constantly - it is natural. This does not demand any form of scientific education, just reflections and the use of common sense. Explanations can be very simple or very complex and we can call them theories which are the results of thoughts, studies and discussions with others. The most important with models is that they can give logical explanations for our observations. A model must be a possible explanation to what we have seen.
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Arrange and understand
Scientific procedure
Observations and models
Hypotheses and predictions
Null hypothesis
Temporarily valid
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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson