RRB Nsg. Superintendent-21 July 2019 (Shift-2nd)
Nursing Research & Statistics
Easy

The relationship between two or more variables is called

Appeared in: RRB Nsg. Superintendent-21 July 2019 (Shift-2nd)

Explanation

  • Correlation is a statistical measure that expresses the extent to which two or more variables are linearly related, meaning they change together at a constant rate.
  • The question asks for the term that defines the relationship between variables, which is the definition of correlation.
  • The strength and direction of this relationship are measured by the correlation coefficient (r), which ranges from -1 (perfect negative) to +1 (perfect positive).
  • The values (+1, -0.33) in the question are examples of correlation coefficients, further confirming that 'Correlation' is the correct concept.

Why Other Options Were Wrong

  • Option A: A Type I error is a mistake made during hypothesis testing (a 'false positive'), not a measure of the relationship between variables.
  • Option C: A hypothesis is a proposed explanation or prediction about a relationship that is yet to be tested. Correlation is the actual measurement of the relationship after data has been collected.
  • Option D: Research is the broad, systematic process of inquiry. Correlation is a specific statistical technique used within the research process to analyze data.

Related Visual

Visual explanation — Related Visual
  • Visual 1: Scatter Plot Diagrams. A set of three scatter plots illustrating positive correlation (dots trending upwards from left to right), negative correlation (dots trending downwards), and no correlation (dots scattered randomly). This helps visualize the different types of relationships between variables.
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Definition of Correlation in Research and Statistics as background academic context rather than a clinical decision trigger.
  • Understanding correlation is fundamental for evidence-based nursing practice. It allows nurses to critically appraise research articles and understand the relationships between clinical variables, such as the link between a specific intervention and patient outcomes.
  • A key principle for nurses to remember is that 'correlation does not imply causation.' Just because two variables are related (e.g., higher coffee intake and lower risk of a certain disease) does not mean one causes the other. There could be other confounding factors.
  • What if a study reports a correlation coefficient (r) of 0 between two variables? This would mean there is no linear relationship between them. For example, a study might find no correlation between a patient's height and their response time to a particular medication.
How to Approach the Question
  • First, identify the keywords in the question stem: 'relationship' and 'variables'. The question is asking for the specific statistical term that defines this concept.
  • Analyze the options in the context of statistics and research methodology.
  • Evaluate 'Hypothesis' and 'Research'. A hypothesis is a prediction about a relationship, and research is the process of investigating it. Neither is the relationship itself.
  • Evaluate 'Type I error'. This is a specific type of mistake in statistical testing, not a measure of a relationship.
  • Recognize that 'Correlation' is the precise term for a statistical measure of the relationship between variables.
  • The numbers in parentheses (+1, -0.33) are strong clues, representing possible values of the correlation coefficient, which directly points to 'Correlation' as the correct answer.
Concept Tested & Keywords
  • Concept Tested: Definition of Correlation in Research and Statistics
  • Stem keywords: relationship, two or more variables
  • Lead-in keywords: is called

Question ID

Q7Ji8XX3ae984FQs0EDOSV

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