C784 Statistics (Actual 2025/2026) Questions and verified
Answers
3 Types of Percentages on a Two-Way Frequency Table
Right Skewed is positive (tail li.)
Left Skewed is negative (tail .iI)
Right and Left Skew
EXPLANATORY VARIABLE (x/independent) - presumed to
possible cause change in the response variable
RESPONSE VARIABLE (y/dependent) presumed to be affected
by the explanatory variable
Define Explanatory vs Response Variable
aka "r", describes the direction and strength of the relationship
of variables on a scatterplot.
, Between -1 and +1
0 = no correlation
-1 = perfect negative correlation
1 = perfect positive correlation
Correlation Coefficient
aka the line of best fit, y = mx + b
slope is m
b is y intercep
y is y (response) variable
x is x (explanatory) variable
Linear Regression Equation
Impossible = 0% possibility
Unlikely = 1% to 30% probability
As likely as unlikely = 40% to 60% probability
Likely - 70% to 99% probability
Certain - 100% probability
Qualitative Descriptions with their Quantitative Probability
Answers
3 Types of Percentages on a Two-Way Frequency Table
Right Skewed is positive (tail li.)
Left Skewed is negative (tail .iI)
Right and Left Skew
EXPLANATORY VARIABLE (x/independent) - presumed to
possible cause change in the response variable
RESPONSE VARIABLE (y/dependent) presumed to be affected
by the explanatory variable
Define Explanatory vs Response Variable
aka "r", describes the direction and strength of the relationship
of variables on a scatterplot.
, Between -1 and +1
0 = no correlation
-1 = perfect negative correlation
1 = perfect positive correlation
Correlation Coefficient
aka the line of best fit, y = mx + b
slope is m
b is y intercep
y is y (response) variable
x is x (explanatory) variable
Linear Regression Equation
Impossible = 0% possibility
Unlikely = 1% to 30% probability
As likely as unlikely = 40% to 60% probability
Likely - 70% to 99% probability
Certain - 100% probability
Qualitative Descriptions with their Quantitative Probability
