Stats quiz 11,12,14,15,16

In a repeated measure design, uD is sometimes equal to 0

F

A repeated measures design can be used to study changes over time

T

A researcher would like to compare before and after effects of a treatment with 30 sets of scores. This means the study will require 60 participants.

F

The null hypothesis in an ANOVA states that all of the group means are unequal.

F

F-ratios are always greater than or equal to zero

T

The distribution of F ratios is negatively skewed

F

An F ratio near 1.0 is an indication that the null hypothesis is likely to be true

T

SSbetween measures each sample variance

F

For an ANOVA, comparing four groups, dfbetween = 3

T

For an ANOVA, comparing three groups with 10 in each group, dftotal = 29

T

A negative correlation means that increases in one variable tend to be accompanied by increases in the other variable.

F

If the value of the correlation is r = -1.0, then all data points in a scatter plot fit perfectly on a straight line

T

A correlation of r = -0.90 indicates that the data points are clustered close to a line that slopes (points) up to the right

F

Correlation = Causation

F

The value of a correlation ranges from -1.0 to +1.0

T

If data points in a scatter plot are clumped together, then the correlation is near zero.

T

A value of r = -0.95 means that there is a strong relationship between two variables

T

The number of hours a person exercises and their gender is an example of a bivariate relationship

F

A researcher obtains a correlation of r = -0.41 between the amount of time each student studies for exam and their exam score. This means that people who studied more got better grades.

F

A correlation of r = 0.70 is stronger than a correlation of r = -0.80

F

The larger the difference among the sample means, the larger the numerator of the F-ratio will be

T

In an ANOVA, post hoc tests are only needed if H? is rejected and there are more than 2 groups

T

The Bonferroni test helps to reduce Type II Error

F

As the number of comparisons increases, Type I Error decreases

F

If an F ratio is equal to 25, then the t-statistic would be equal to 5

T

In ANOVA, MS values measure sample variance

T

The shape of the F distribution depends on the degrees of freedom (df)

T

An interaction examines the effect of one IV averaged across the levels of another IV

F

In a two-way anova, two hypothesis are tested

F

In a two-way ANOVA, there are two dependent variable

F

The SP determines the sign of the correlation

T

The correlation df formula is n-1

F

Homoscedasticity is a factor that affects correlations

F

In regression, error assesses the difference between predicted values and actual values

T

If a correlation coefficient is 0.40, then the coefficient of determination would be 0.20

F

In the linear equation, Y = bX + a, a indicates the X-intercept

F

The regression line indicates the center of the data

T

In regression, the slope determines the direction of the relationship

T

Regression is used to make predictions

T