#1
What does a correlation coefficient measure?
Strength of the relationship between two variables
ExplanationQuantifies the degree of association between two variables.
#2
Which value indicates a perfect negative linear correlation?
-1
ExplanationIndicates a perfectly negative linear relationship between variables.
#3
What does a negative correlation coefficient indicate?
Inverse relationship between variables
ExplanationShows an inverse relationship between variables.
#4
When calculating the Pearson correlation coefficient, what is the range of possible values?
Between -1 and 1
ExplanationPossible values range from perfect negative correlation to perfect positive correlation.
#5
What does a correlation coefficient of 0 indicate?
No linear correlation
ExplanationShows absence of linear relationship between variables.
#6
Which of the following correlation coefficients indicates the strongest linear relationship?
0.9
ExplanationIndicates a very strong positive linear relationship between variables.
#7
What does a correlation coefficient of -1 indicate?
Perfect negative correlation
ExplanationDenotes a perfect negative linear relationship between variables.
#8
What does a correlation coefficient of 0.75 indicate?
Strong positive linear correlation
ExplanationShows a strong positive linear relationship between variables.
#9
What is the range of values for a correlation coefficient?
Between -1 and 1
ExplanationCorrelation coefficient ranges from perfect negative correlation (-1) to perfect positive correlation (1).
#10
Which type of correlation analysis is suitable for non-linear relationships?
Spearman correlation
ExplanationSuitable for analyzing non-linear relationships between variables.
#11
Which statement about correlation and causation is true?
Correlation does not imply causation
ExplanationCorrelation between variables does not necessarily imply a causal relationship.
#12
Which correlation coefficient is more robust to outliers: Pearson or Spearman?
Spearman
ExplanationLess sensitive to outliers compared to Pearson correlation.
#13
Which statistical test is used to determine if a correlation coefficient is significantly different from zero?
t-test
ExplanationUsed to assess if correlation coefficient significantly differs from zero.
#14
In linear regression, what is the role of the correlation coefficient?
Determining the strength of the relationship between variables
ExplanationIndicates the strength and direction of the linear relationship.
#15
What does a correlation coefficient close to zero suggest?
Weak or no linear correlation
ExplanationIndicates weak or no linear relationship between variables.
#16
Which of the following scatter plots indicates a perfect positive linear correlation?
A scatter plot with points forming a diagonal line sloping upwards
ExplanationShows a clear pattern of positive linear relationship between variables.
#17
In which case would the Spearman correlation coefficient be more appropriate than the Pearson correlation coefficient?
When the data is not normally distributed
ExplanationPreferred when data violates assumptions of normality or contains outliers.
#18
What is the formula for calculating the Pearson correlation coefficient?
r = Σ(x - x̄)(y - ȳ) / √(Σ(x - x̄)² * Σ(y - ȳ)²)
ExplanationFormula to quantify the strength and direction of a linear relationship between two variables.