1. PROBLEM Fundamental principle
If we want to solve a problem, one must generally know what the problem is:
Problem
Scientific problem
A good statement problem : (no one right: way to state one). The problem of published by Hurlock (Kerluiser, 1973)
Exp:
1. what are the affects of public performance at different types of incentives. ? (Question form)
● The simplest way is here the best way
● The problem states a relation between variabels
A problem, is an interogative sentence or statement That asks:
“What relationship between two or more variables”
2. Do teacher’s comments cause improvement in student performance ?
X1 teacher comment
X2 Student performance
The ralation part → “cause”

2. Criteria of good problem statement
1. The problem should express a relation between two or more variables.
Exp: Is A related to B ?
How are A and B related to C
How is A related to B under condition C and D ?
2. Problem should be stated clearly and unambigiuosly in question form.
3. Problem statement should be such as to imply possibilities of empiricial testing.

3. CONCEPT
Concept is an abstraction-a symbol- a respresentation of an object or one of its properties, or of a behavioral phenomenon. For example: “social status”, “power”, “bureaucracy”.
Each scietific discipline develops its unique set of concepts.
Four Function of Concept:
1. Concept provides a common language, which enable scientist to ccommunicate with one another.
2. Concept gives scientiest a perpective a way of looking phenomenon
3. Concept allows scientist to classify their experiences and to generalize from them.
4. Concept is components of theories it defines a theory’s content and attributes.

4. Conceptual Definition
Definitions that describe concepts by using other concepts. For example: “power” has been conceptually defined as the ability of an actor (an individual, a group) to get another actor to do something.
Primitive Term, is a concept that can not be defined by other concepts. For example: color, smell, sound.
Operational definition is definitions that provide concepts with empirical referents. Operational definition bridges the conceptual-theoretical and empirical-observational levels. Operational definition defines what to do and what to observe.