Methods of Psychology

• Hypothesis: A tentative statement about how or why something happens.

• e.g. non experienced teachers use corporal punishment more than experienced teachers.

* Independent variable: manipulated by experimenter, cause (teachers experience).

*Dependant variable: expected to change when the independent variable change, effect → student's ways of punishment

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 Types of researches in psychology

• A-Experimental research:

-A research designated to answer questions about cause and effect (causal relationship).:

(1) Experimental group: experience the experimental condition.

(2) Control group: has similar characteristics to the experimental group, but does not experience the experimental condition.

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Types of researches in psychology… cont.

B- Correlation research: Test two variables are related to each other.

- Positive correlation: means that a high incidence of one variable accompanied by a high incidence of the other.

• -Negative correlation: means that a high incidence of one variable accompanied by low incidence of the other.

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Types of researches in psychology… cont.

• - Correlation coefficient: indicate the strength of correlation between study variables.

• Ex: If you know that a student is intelligent, you predict that he will make good in the exam (positive correlation).

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Types of researches in psychology… cont.

D- Naturalistic observations:

• researcher use covert observation naturally.

- psychologists can record behaviors as it occurs in real life.

- Participant observation: the researchers join the group to be studied to record their thoughts and feelings.

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Types of researches in psychology… cont.

• E- Case Study:

- Research method in which one individual is explored in depth. (from all aspects).

- used when the disorder is rare and few cases are available as in multiple personality disorder.

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Types of researches in psychology… cont.

• F- Longitudinal study:

• Research method in which group of people is examined at intervals over a number of years.

• Used in developmental psychology, (more reliable but it is time consuming).

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Types of researches in psychology… cont.

G- Cross sectional study:

• Research method in which people of different ages are examined simultaneously, example: IQ (intelligence quotient) to people of different ages and then draw differences of intelligence through life cycle.

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Data collection

1- Observation: is a simple method of data collection :

a.covert observation: in which people are not informed they are being observed

(limitation is lack of ethical consideration).

b. Overt observation: people are informed they are being observed,

(ethical but they may change their behavior positively).

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2- Interviews: letting the researchers to speak with their subjects.

(validity and consistency may be compromised).

3-Questionnaires: less time, useful with large group of people.

4- Self-reports: people are asked to report about their thinking and feeling.

(used with highly educated people, as in cognitive psychology).

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Evaluation of Psychological measurement techniques

• Measurement tools are evaluated for its accuracy through:

• 1- Validity:

a measurement device is valid if it does measurer what it is intended to measure.

• Ex. If you try to gauge intelligence by measuring the shape of person’s head, (invalid measurement) head shape has nothing to do with intelligence.

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2-Reliability:

- Device is reliable when it yields constantly similar results, when it is applied repeatedly at the same sample under similar conditions.

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Sampling

• sample: segment (part) of population being studied.

• -If psychologists are going study human behavior, they can’t ask the whole population, they use sample, then they generalize their conclusions to the general target population.

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Good method of sample selection based on:

a- Random sample: every one in the total population has an equal chance of being included.

b- Representative sample: subgroups with distinct characteristics are included according to their proportion in the total population. (includes limits).

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*Bias in psychological research:

• Researchers may make their hypothesis true during data collection and application of tool.

• Ex. when conducting interview they smile at desirable responses.

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The ethics of research in psychology:

• 1-Informed consent: participating in study is voluntary, with agreement.

• 2-Freedom from harm: protect participants from physical and mental harm.

• 3-Privacy and confidentiality

• 4- Experimentation is forbidden to be on human firstly.

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The ethics of research in psychology … cont.

• 5- Consideration of cultural or religious background of the subjects.

• 6- Subjects should receive full information before study.

• 7- Subjects has the right to withdraw at any stage of study.

• 8- Sharing the results with subjects and professionals in the community.

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