The Scientific Method

THE SCIENTIFIC METHOD

The Scientific Method is a process of investigation that is used to explore an observation and answer a question.  It is a systematic process which tries to unlock the mysteries of the natural world. It uses repeated observations and experimental evidences to search for cause and effect relationship in nature.

Steps in the Scientific Method

1.      Observation

Almost all scientific inquiries start with observation.  Observation is the act of perceiving the things that are happening in the environment through our senses. People tend to have a life that is normal and routinely. However, if something does not conform to the expected way of life then probably a problem is occurring.

Ex: You observed that farmers put fertilizers to plants.

2.      Identifying the Problem

The problem is the question which you will try to resolve. The following conditions must be met to properly identify the problem:

a.      Recognize that there is a problem. Remember to answer just one question at a time.

b.      Clearly state the problem so you will know what you are trying to solve but make sure that results are measurable or at least ca n be rated qualitatively.

c.       Put the problem in the form of a question.

Ex: How does fertilizer affect the growth of plants?

3.      Formulating Hypothesis

Once the problem is identified and testable question has been proposed, you can now formulate a hypothesis. Hypothesis is a simple statement that presents the possible solution to the problem. It is an educated guess which aims to solve the problem. This makes the hypothesis the turning point of the research. To properly word the hypotheses:

a.      Do a background research to come up with the best probable solution to the problem.

b.      State the hypothesis in a way to help you answer the original problem.

c.       Identify the variables and make sure that only one variable is manipulated at a time.

Hypothesis may be stated in two ways:

1.      Null hypothesis (Ho) states that there is no relationship between variables.

Ex: The fertilizer does not affect the growth of plants. (Ho: A = B)

2.      Alternative Hypothesis (Ha) states that there is a relationship between variables.

Ex: There is a significant relationship between the use of fertilizer and the growth of plants. (Ha₁: A ≠ B)

            Alternative Hypothesis can also be stated in two ways:

            Ha₂: A < B        There is a negative relationship between A and B.

                                    The lesser the fertilizer, the more the plant grows.

            Ha₂: A > B        There is a positive relationship between A and B.

                                    The more fertilizer is applied, the more the plant grows.

4.      Testing the Hypothesis and Gathering of Data

Experiment is a set of manipulations or specific observations of nature and is considered the most important part of scientific method. It is done to answer the research question or investigate a problem. It is used to prove or disprove the hypothesis.

There are three types of experiment. These are as follows:

1.      Natural Experiment or Quasi-Experiments

These are experiments that rely solely on observations of the variables of the system under study. The observer does not manipulate any variable but simply collect all the possible data to determine the factors affecting a particular phenomenon.  A field of science that employs the natural experiment is astronomy.

2.      Field Experiment

It examines the real world using scientific method and often used in social sciences such as political sciences, economics and psychology.

3.      Controlled Experiment

It compares the results obtained from an experimental sample against the control sample. The observer tests a hypothesis by looking for changes brought about by alteration of variable. This type of experiment is usually done in laboratories.

Variable – a characteristic, number or quantity that increases or decreases over time or takes different values in different situation. There are three kinds of variables in an experiment.

a.      Controlled Variables -  these are the variables that are kept constant.

Ex: Amount of water, sunlight received by the plants, temperature, amount and type of soil, the size of the pot and the number and type of plant.

b.      Independent Variables – these are factors that is being changed or altered during the experiment. These variables cause corresponding effect on other variables.

Ex: The amount or presence of nitrogen fertilizer.

c.       Dependent Variables – observable factors that are considered response to an independent variables.

Ex: The growth of plants in terms of height, number of leaves and other characteristics.

5.      Analyzing Data

Data obtained from experiments should be analyzed and presented systematically. Data are usually presented trough graph, table, charts and the like. The data gathered trough the experiment conducted can be presented this way.

SET UP	Height of Plants (cm)
	0 Days	5 Days	10 Days	15 Days
A (with fertilizer)	0	3	5	11
B (without Fertilizer)	0	1	3	7

Through the given table, we can now make an analysis.

Ex:  From the given data, the plant treated with fertilizer grows faster compared to the plant treated with no fertilizer.

6.      Drawing Conclusion

Looking at the analysis of your data, see if the information you gathered answers your problem. Based on your findings, you can now make a conclusion. Please note that your conclusion answers the problems.

Example:

Problem: How does fertilizer affect the growth of plants?

Conclusion: I therefore conclude that fertilizers help in the growth and development of plants.

NOTE: If the hypothesis is proven to be true, perform again the experiment for several times to be sure that results gathered are true, factual and accurate. If the hypothesis is not true or partly true, modify the hypothesis and perform the method all over again.

7.      Report Results

It will be good to have someone else look at your findings to help you find any mistakes or unusual results. This will help you improve your procedure the next time you conduct an experiment.