What is directional vs non directional hypothesis?

Here's a breakdown of directional vs. non-directional hypotheses:

In research, a hypothesis is a testable prediction about the relationship between two or more variables. Hypotheses can be categorized as directional or non-directional, based on the specificity of the predicted relationship.

• Directional Hypothesis (One-tailed Hypothesis):

  • A directional%20hypothesis specifies the direction of the relationship between variables.
  • It predicts not only that there will be a relationship, but also which variable will be higher or lower, or whether the relationship will be positive or negative.
  • Example: "Increased study time will lead to higher exam scores." (Predicts a positive relationship)
  • Example: "Lack of sleep will cause lower job performance." (Predicts a negative relationship)
  • These are tested using one-tailed statistical tests.

• Non-Directional Hypothesis (Two-tailed Hypothesis):

  • A non-directional%20hypothesis predicts that there will be a relationship between variables, but it does not specify the direction of that relationship.
  • It simply states that the variables will influence each other.
  • Example: "There will be a relationship between exercise and weight." (Does not say whether exercise will increase or decrease weight).
  • Example: "There is a difference in anxiety levels between students who use social media and those who don't."
  • These are tested using two-tailed statistical tests.

Key Differences Summarized:

Feature	Directional Hypothesis	Non-Directional Hypothesis
Relationship	Predicts the direction of the relationship.	Predicts a relationship exists, but not the direction.
Specificity	More specific.	Less specific.
Tail	One-tailed test.	Two-tailed test.
When to Use	When prior research suggests a specific direction.	When there's little or no prior research, or conflicting findings.
Example	"Students who study more will achieve higher grades."	"There is a relationship between studying and grades."