#1
What does a correlation coefficient measure?
Strength of the relationship between two variables
Causation between two variables
Magnitude of one variable
Direction of one variable
#2
Which value indicates a perfect negative linear correlation?
#3
What does a negative correlation coefficient indicate?
No relationship between variables
Inverse relationship between variables
Positive relationship between variables
Perfect relationship between variables
#4
When calculating the Pearson correlation coefficient, what is the range of possible values?
Between -1 and 0
Between 0 and 1
Between -1 and 1
Between 0 and infinity
#5
What does a correlation coefficient of 0 indicate?
Perfect positive correlation
Perfect negative correlation
No linear correlation
Infinite correlation
#6
Which of the following correlation coefficients indicates the strongest linear relationship?
#7
What does a correlation coefficient of -1 indicate?
Perfect positive correlation
Perfect negative correlation
No linear correlation
Infinite correlation
#8
What does a correlation coefficient of 0.75 indicate?
Strong positive linear correlation
Weak negative linear correlation
No linear correlation
Perfect negative linear correlation
#9
What is the range of values for a correlation coefficient?
Between -1 and 0
Between 0 and 1
Between -1 and 1
Between 0 and infinity
#10
Which type of correlation analysis is suitable for non-linear relationships?
Pearson correlation
Spearman correlation
Point-biserial correlation
Phi coefficient
#11
Which statement about correlation and causation is true?
Correlation implies causation
Causation implies correlation
Correlation does not imply causation
Causation does not imply correlation
#12
Which correlation coefficient is more robust to outliers: Pearson or Spearman?
Pearson
Spearman
Both are equally robust
Neither is robust to outliers
#13
Which statistical test is used to determine if a correlation coefficient is significantly different from zero?
t-test
ANOVA
Chi-square test
Z-test
#14
In linear regression, what is the role of the correlation coefficient?
Determining the strength of the relationship between variables
Predicting future values
Calculating the intercept
None of the above
#15
What does a correlation coefficient close to zero suggest?
Strong linear correlation
Weak or no linear correlation
Perfect linear correlation
Non-linear correlation
#16
Which of the following scatter plots indicates a perfect positive linear correlation?
A scatter plot with points forming a horizontal line
A scatter plot with points forming a vertical line
A scatter plot with points forming a cluster
A scatter plot with points forming a diagonal line sloping upwards
#17
In which case would the Spearman correlation coefficient be more appropriate than the Pearson correlation coefficient?
When the data is not normally distributed
When the relationship between variables is strictly linear
When outliers are present
When the variables are continuous
#18
What is the formula for calculating the Pearson correlation coefficient?
r = Σ(xy) / √(Σx² * Σy²)
r = Σ(x - x̄)(y - ȳ) / √(Σ(x - x̄)² * Σ(y - ȳ)²)
r = Σxy / (Σx * Σy)
r = Σ(x - x̄)(y - ȳ) / (Σ(x - x̄) * Σ(y - ȳ))