WorksheetsStatistics Quiz
Total questions: 40
Worksheet time: 20mins
Which of the following best describes a factorial design?
A study with more than one factor
A study with only one factor
A study with repeated measures
A study with only dependent variables
In a two-factor ANOVA, how many hypothesis tests are conducted?
One
Three
Four
Two
What does a main effect represent in a two-factor ANOVA?
The correlation between factors
The effect of one factor averaged across levels of the other factor
The combined effect of both factors
The error variance
What indicates an interaction in a two-factor ANOVA graph?
No variance
Parallel lines
Non-parallel lines
Equal means
Which formula represents the F-ratio?
Mean differences / Sample size
Sum of squares total / Degrees of freedom
Variance between treatments / Variance expected by chance
Eta squared / Variance
What is the purpose of adding a second factor in ANOVA?
To increase variance
To avoid hypothesis testing
To reduce variance caused by individual differences
To eliminate main effects
Which assumption is NOT required for two-factor ANOVA?
Normality of populations
Equal sample sizes
Independence of observations
Equal variances
What is eta squared (η²) used for?
Computing correlation
Testing normality
Calculating degrees of freedom
Measuring effect size
Which of the following is true about correlation?
It measures the relationship between two variables
It measures causation
It measures regression slope
It measures variance explained by ANOVA
A positive correlation means:
No relationship exists
As X increases, Y increases
The slope is negative
As X increases, Y decreases
The null hypothesis in correlation states:
ρ ≠ 0
ρ = 0
ρ > 0
ρ < 0
Degrees of freedom for Pearson correlation are:
n - 1
n - 3
n
n - 2
Which correlation is used for ordinal data?
Phi-coefficient
Point-biserial
Pearson
Spearman
The coefficient of determination (r²) indicates:
Slope of regression line
Strength of correlation
Percentage of variance explained
Error variance
Which correlation is used when one variable is dichotomous?
Spearman
Point-biserial
Pearson
Phi-coefficient
Which correlation is used when both variables are dichotomous?
Phi-coefficient
Spearman
Pearson
Point-biserial
Regression is used to:
Compute chi-square
Predict values of Y from X
Test independence
Measure variance
In the regression equation Ŷ = bX + a, what does b represent?
Slope
Error
Intercept
Variance
In the regression equation Ŷ = bX + a, what does a represent?
Slope
Intercept
Variance
Error
Which of the following is NOT a use of regression?
Predicting Y from X
Measuring correlation strength
Estimating slope and intercept
Testing independence of categorical variables
The regression constant “a” is also called:
Slope
Intercept
Variance
Error
The least-squares regression line minimizes which of the following?
Variance between treatments
Sum of squared errors between predicted and actual Y
Correlation coefficient
Chi-square statistic
The standard error of estimate measures:
Strength of correlation
Average distance between predicted and actual Y values
Variance explained by regression
Degrees of freedom
In regression, the slope (b) can also be computed using:
Eta squared
Pearson correlation and standard deviations
Chi-square formula
ANOVA F-ratio
Multiple regression allows:
Testing independence of categorical variables
Using several predictors to improve accuracy
Eliminating variance completely
Measuring only one variable
In multiple regression, the equation is:
Ŷ = bX + a
Ŷ = b1X1 + b2X2 + a
F = MSbetween/MSwithin
r = Σ(ZxZy)/N
The symbol R² in regression indicates:
Percentage of variance explained by regression
Correlation coefficient
Error variance
Degrees of freedom
Which test is nonparametric?
t-test
ANOVA
Chi-square
Regression
Parametric tests require:
Frequency counts
Interval or ratio data
Ordinal data only
Dichotomous variables
The chi-square test for goodness of fit evaluates:
Mean differences
Proportions in categories
Regression slopes
Correlation strength
Observed frequency (fo) refers to:
Expected counts from hypothesis
Actual counts from sample data
Variance explained by regression
How is the expected frequency (fe) calculated?
fe = pn
fe = ΣX²/n
fe = r² × SSY
fe = MSbetween/MSwithin
Which of the following is the correct formula for the chi-square statistic?
F = MSbetween/MSwithin
χ² = Σ((fo - fe)² / fe)
r = SP/(SSX·SSY)
Ŷ = bX + a
What is the formula for degrees of freedom for chi-square goodness of fit?
n - 1
C - 1
n - 2
(R - 1)(C - 1)
How do you calculate the degrees of freedom for chi-square independence?
n - 1
C - 1
(R - 1)(C - 1)
n - 2
When is the phi-coefficient used?
Both variables are dichotomous
One variable is ordinal
One variable is dichotomous, one continuous
Both variables are continuous
Cramer's V is used when:
Both variables are continuous
Matrix larger than 2×2
One variable is ordinal
Regression with two predictors
A chi-square test should not be used when:
Expected frequency < 5 in any cell
Sample size is large
Variables are categorical
Observed frequencies are integers
Which of the following is true about nonparametric tests?
They require interval data
They are distribution-free
They always use regression
They cannot test independence
The chi-square test for independence evaluates:
Whether two categorical variables are related
Whether regression slope is significant
Whether correlation is zero
Whether means differ across treatments
