[align=left]Formulation and statement of a hypothesis
Definition: hypothesis
a hypothesis is a tentative explanation for certain behaviours, phenomena, or events that have occurred or will occur. A hypothesis states the researcher's expectations concerning the relationship between the variables in the research problem.
So we can say that,
A hypothesis is a specific statement of prediction. It describes in concrete (rather than theoretical) terms what you expect will happen in your study.
Also we can say that hypothesis states what the researcher thinks the outcome of the study will be. The researcher does not then set out to ''prove'' his or her hypothesis, but rather collects data that either support the hypothesis or do not support it; research studies do not prove anything.
Hypothesis are essential to all research studies with the possible exception of some descriptive studies whose purpose is to answer certain specific questions.
THE DIFFERENCE BETWEEN A HYPOTHESIS AND A PROBLEM
Both a hypothesis and a problem contribute to the body of knowledge which supports or refutes an existing theory. A hypothesis differs from a problem. A problem is formulated in the form of a question; it serves as the basis or origin from which an hypothesis is derived. A hypothesis is a suggested solution to a problem. A problem (question) cannot be directly tested, whereas a hypothesis can be tested and verified.
WHEN IS A HYPOTHESIS FORMULATED?
A hypothesis is formulated after the problem has been stated and the literature study has been concluded. It is formulated when the researcher is totally aware of the theoretical and empirical background to the problem.
THE PURPOSE AND FUNCTION OF A HYPOTHESIS
1- It offers explanations for the relationships between those variables that can be empirically tested.
What are Variables ?
Scientists use an experiment to search for cause and effect relationships in nature. In other words, they design an experiment so that changes to one item cause something else to vary in a predictable way.
These changing quantities are called variables. A variable is any factor, trait, or condition that can exist in differing amounts or types. An experiment usually has three kinds of variables: independent, dependent, and controlled.
Hypotheses are tentative statements of the expected relationships between two or more variables
There is a significant positive relationship between self-concept and math achievement
The class using math manipulatives will show significantly higher levels of math achievement than the class using a traditional algorithm approach
2- It furnishes proof that the researcher has suffucient background knowledge to enable him/her to make suggestions in order to extend existing knowledge.
3- It gives direction to an investigation.
4- It structures the next phase in the investigation and therefore furnishes continuity to the examination of the problem.
CHARACTERISTICS OF A HYPOTHESIS:
See your hand out at page 67 to 68.
TYPES OF HYPOTHESES
Hypotheses can be classified in terms of their derivation (how they are derived), (inductive and deductive hypotheses) and in terms of their formulation (how they are stated), (research – declarative hypothesis and statistical or null hypotheses).
Inductive and deductive
Inductive hypotheisi is a generalization based onobsrevation.
Deductive hypotheses derived from theory.
Research or statistical
Research hypotheses are stated in declarative form.
They states an expected relationship or difference between two variables.
These research hypotheses are divided to:
Directional: indicates the nature of the relationship or difference:
(e.g., the class using manipulatives will demonstrate higher achievement levels than the class using a traditional instructional approach)
Non-directional: indicates that a relationship or difference exists:
(e.g., there will be achievement differences between the groups of children using co-operative group strategies or individualized instruction)
Statistical hypotheses are stated in null form.
Null hypothesis: states that there is no difference or relationship between variables, and that any relationship found will be a chances relationship, not a true one.
So we can call the hypothesis that you support (your prediction) the alternative hypothesis, and we call the hypothesis that describes the remaining possible outcomes the null hypothesis. You have to be careful here, though. In some studies, your prediction might very well be that there will be no difference or change. In this case, you are essentially trying to find support for the null hypothesis and you are opposed to the alternative.
How to State a Statistical Hypothesis:
Stating a statistical hypothesis is a necessary and essential part of statistical inference. In order to formulate a statistical test, usually some idea or theory has been suggested and the statistical test is designed to determine whether or not the idea is statistically significant. This article will show you how to state a statistical hypothesis using the example of determing whether or not there is a difference in taste between soft drink 1 and soft drink 2.
Step1
You have designed an experiment to determine whether or not there is a difference between the taste of soft drink 1 and soft drink 2.
Step2
State the null hypothesis, H0 or Ho, as "there is no difference in taste between soft drink 1 and soft drink 2". In other words, there are no statistically significant differences between the two.
Step3
State the alternate hypothesis, H1 or Ha, as "there is a difference in taste between soft drink 1 and soft drink 2". In other words, the difference is statistically significant.
Step4
If, after carrying out your experiment or test, you discover that there is no statistically significant difference between the taste of the two soft drinks, then you "fail to reject the null hypothesis".
Step5
However, if after carrying out your experiment or test, you discover that there is a statistically significant difference between the taste of the two soft drinks, then you "reject
Tips & Warnings
• The null hypothesis relates to the statement being tested.
• The alternate hypothesis relates to the statement to be accepted if and when the null hypothesis is rejected.
• As stated in steps 4 and 5, the final conclusion of the test is always stated in terms of the null hypothesis: either "fail to reject the null" or "reject the null".
• Failing to reject the null does not necessarily mean the null hypothesis is true, it just means there is not enough sufficient evidence to reject the null hypothesis in favor of the alternate.
• One of two errors may occur in statistical hypothesis testing:
• Type I Error - Rejecting the null hypothesis when in fact there are no statistically significant differences.
• Type II Error - Failing to reject the null hypothesis when in fact there are statistically significant differences.
Testing the hypothesis:
Handout page 72.
can you give me some Examples of Hypotheses?
* "If I open the faucet [faucet opening size is the independent variable], then it will increase the flow of water [flow of water is the dependent variable].
* "Raising the temperature of a cup of water will increase the amount of sugar that dissolves ."
* "If a plant receives fertilizer [having fertilizer is the independent variable], then it will grow to be bigger than a plant that does not receive fertilizer " .
* "If I put fenders on a bicycle , then they will keep the rider dry when riding through puddles " . [/align]
Formulation and statement of a hypothesis
العرض العادي
