Introduction To Psychology (Unit 2) an der University of the West Indies, Cave Hill

A hypothesis is a falsifiable prediction made by a theory.

A specific statement about behaviour or mental process that is tested through research. 

Step 1 - Psychological Theory- Daily experiences or commonly held beliefs.

Step 2: Research question or Hypothesis 

Step 3: Examining the research question/ test hypothesis/ review literature. 

Step 4: Gather Evidence (i.e experiment/ observations, surveys)

Step 5: Draw Conclusion 

Step 6:  Construct/ modify the theory 

Step 7: New research question/ hypothesis

A research question is a question that the research project sets out to answer. 

A hypothesis, on the other hand, is not a question. It is a statement about the relationship between two or more variables. 

This is the belief that accurate knowledge can be acquired through observation. 

A variables something that can be changed. ( i. e religion, age, height, size and exercise.) 

Variables can be accurately and must be measured and identified. 

Determinism - The belief that everything has a cause. All events are completely determined by previous events, whether involving inanimate matter or conscious beings like humans.

Empiricism – Knowledge by observation. Conclusions must be based on recording and analyzing observations. Evidence such as faith, stories, myth, rumors, or other “data” that cannot be publicly observed or verified are rejected. For example, the amount of “anxiety” a person feels cannot be observed, however, we can observe that person’s behaviour, including how that person answers a series of questions related to how anxious he/she feels. 

Replication – All claims should be duplicated by a third party. It is believed, if something (results or systematic steps) cannot be duplicated, then it probably happened because of an accident or someone made an error somewhere. For example, someone should be able to use the same analytical procedure you have used and find the same results. 

Uncertainty – It is impossible to know everything about anything, but it is always possible to know more about anything.

 Relativism – All things have characteristics that make them similar to other things, as well as characteristics that make them dissimilar to other things. For example, a male and female have common characteristics such as two feet, a mouth, and so on. However, they also have some dissimilar characteristics such as different reproductive systems and different sex organs.

There are five types of validity:

Construt Vadilty

(i.e ensure that the scale/ experiment measures the specific constructs.)

Predictive Validity 

(i.e the research predicts future outcomes.)

Content Validity 

The items on yje test represent the entire range of possible items the test should cover.

Internal Validity

Researcher controls all extraneous variables and only variables influencing the result of a study are manipulated. 

External Validity

Can the result be generalised to the larger population. 

Sampling is a partial collection of people drawn from a population. (Schacter et al, 2018)

There is Random Sampling and Stratified Sampling.

Research Sampling: each member of the population has an equal chance of being selected.

Stratified Reserch: only identifies groups that are proportionally represented.

WHAT IS MANIPULATION? Manipulation is the process by which researchers intentionally alter, change or impact a variable in an experimental research design. 

WHAT IS THE THIRD VARIABLE?  

The third variable, which is also known as the confounding variable, refers to the variable that researchers fail to eliminate, control or notice, which results in damaging the internal validity of an experiment. It influences both the independent variable and the dependent variable.

Psychologists are interested in manipulation and the third variable because they both play an important part in experiments and research. Manipulation is a critical tool in experiments, it helps rule out alternative hypotheses. Researchers can alternate a variable to establish whether or not changes in one variable would cause resultant changes in another variable. When manipulation is performed, two groups are created: an experimental group and a control group. An experimental group includes subjects who are exposed to the experimental treatment, while the control group consists of subjects who are not exposed to that experimental treatment. This allows the researchers to compare the treatment of the two groups and determine any casual effects. The third variable can severely affect experiments and results if it is not controlled or taken into consideration. It helps with the correlational research, which is a method of study where the researcher measures two or more variables for association between them.

Characteristics of Experimental Research 

• The only type of study that allows for statements of cause and effect. 
•  The person conducting has control over key variables that are not possible in other research designs. 
•  It focuses on the casual impact of one or more experimental manipulation on a dependent variable. 
• Independent and dependent variables Consists of both experimental and control groups  
• Has random assignment to groups Has independent and dependent variables 
• Controlled manipulation – consists of at least one independent variable.

Correlational Research, on the other hand: 

• Examines the relationship between two variables. 
• Cannot say that one variable causes the other .
• The variables are just related.
• Positive, negative or zero 
•  Strength and relationship measures from -1.0 to 1.0 
•  Correlational (r) correlated