III FINALS

PEARSON R

- Most common method to USE FOR NUMERICAL VARIABLES.

- A MEASURE OF THE STRENGTH OF THE LINEAR RELATIONSHIP between two variables.

- The CORRELATION COEFFICIENT takes on values ranging between -1 and +1.

3 TYPES OF CORRELATION

1. Positive Correlation

2. Negative Correlation

3. No Correlation

POSITIVE CORRELATION

- As ONE VARIABLE INCREASES, the OTHER INCREASES too.

• Teaching performance affects the performance of the students positively.

• As the performance of the teacher increases the performance of the students too.

NEGATIVE CORRELATION

As ONE VARIABLE INCREASES, the OTHER DECREASES. On the other hand, as one variable decreases, the

other increases.

• Waiting time and customer satisfaction.

• As your waiting time increases, the satisfaction decreases.

NO CORRELATION

- One variable DOES NOT AFFECT the other variables.

NONE OR VERY WEAK RELATIONSHIP

R < 0.30

WEAK RELATIONSHIP

0.30 < R < 0.50

MODERATE RELATIONSHIP

0.50 < R < 0.70

STRONG RELATIONSHIP

R > 0.70

SPEARMAN RANK CORRELATION

- It is the NONPARAMETRIC VERSION OF THE PEARSON product-moment correlation.

- It MEASURES THE STRENGHT and DIRECTION of ASSOCIATION BETWEEN TWO RANKED VARIABLES.

- The CORRELATION COEFFICIENT takes on values ranging between -1 and +1.

T-TEST

− It is used to determine if the SCORES OF TWO GROUPS DIFFER on a SINGLE VARIABLE.

T-TEST INDEPENDENT

- It is used to COMPARE TWO SAMPLE MEANS when the two samples are INDEPENDENT OF ONE ANOTHER.

− It is the most commonly used METHOD TO EVALUATE THE DIFFERENCE IN MEANS BETWEEN TWO GROUPS.

DEGREE OF FREEDOM

- Are the MAXIMUM NUMBERS OF LOGICALLY INDEPENDENT VALUES that have FREEDOM OF VARYING IN A SAMPLE DATA SET.

- Are taken INTO CONSIDERATION while studying various hypothesis-testing method in statistics like the t-test method.