Question

Positive correlation

Answer 1

A positive correlation refers to a relationship between two variables in which, as one variable increases, the other variable also tends to increase. Similarly, when one variable decreases, the other also tends to decrease. This type of correlation suggests that there is a direct relationship between the two variables, meaning they move in the same direction.

### Characteristics of Positive Correlation:

1. **Coefficient Value**: Positive correlation is measured using a correlation coefficient, commonly denoted as \( r \). The value of \( r \) ranges from 0 to +1.
- \( r = 0 \) indicates no correlation.
- \( r > 0 \) indicates a positive correlation, with:
- \( 0 < r < 0.3 \) indicating a weak positive correlation,
- \( 0.3 \leq r < 0.7 \) indicating a moderate positive correlation,
- \( 0.7 \leq r < 1 \) indicating a strong positive correlation.

2. **Scatter Plot**: In a scatter plot of the two variables, a positive correlation can be visually identified as a trendline that slopes upward from left to right.

3. **Examples**:
- The relationship between the amount of time spent studying and exam scores. Generally, more study time leads to higher exam scores.
- A correlation between height and weight in a population, where taller individuals tend to weigh more.

### Important Note:
While a positive correlation indicates that two variables move together, it does not imply causation. Just because two variables are positively correlated does not mean that one variable causes the other to change. It's important to investigate other factors and consider the context of the relationship when interpreting correlation data.