ANOVA
Assumptions
SLR
Big Picture
Random
100
A psychologist would like to examine the effects of sugar consumption on the activity level of preschool children. One group gets no sugar, one group gets a small dose, and the third group gets a large dose. The psychologist records the activity level for each child.
What is One-Way ANOVA?
100
Normality of the response variable
What is ANOVA and SLR?
100
The regression model of Predicted MPG = 46.87 - 0.084 Horsepower relates cars' horsepower to their fuel economy (in MPG). If you have a car with 200 horsepower and 36mpg. How far off is the predicted value?
What is 5.93mpg
100
Statistical Significance
What is The probability of getting the result we got by chance is very small?
100
Correlation must be between...
What is -1 & 1
200
An analysis of variances produce SS|(Trt) = 30, SS(E) = 60, and an F-ratio with df(Trt)=2 and df(E)=15. For this analysis, what is the F-ratio?
What is 3.75?
200
Equality of variances in response variable
What is ANOVA and SLR?
200
The correlation between a cereal's fiber and potassium is r=0.903. What percent of the variability in potassium is explained by its linear relationship with the fiber?
What is 0.8154
200
General goal of ANOVA
What is Determine if the averages of the response variable by treatment groups are different? (i.e., does the treatment have an effect on the value of the response variable?)
200
About how many students take ST 370 each semester (all sections)?
What is 550 to 650
300
In a One-Way ANOVA, what does an F-ratio = 1.00 tell us about the treatment effect that has been analyzed?
What is There is no treatment effect?
300
Linearity
What is SLR?
300
Predicted Potassium = 38 + 27Fiber. This is the linear model for fiber (in grams) and potassium (in milligrams). Interpret the slope.
What is For every 1 gram increase in fiber, potassium increases by 27 milligrams.
300
Extrapolation
What is predicting values that fall outside the data range
300
If interaction plots intersect, we expect the interaction term will be...
What is Statistically significant?
400
An analysis of variances produce SS(Trt) = 30, SS(E)= 60, and an F-ratio with df(Trt)=2 and df(E)=15. For this analysis, what is the value of N?
What is 18? 15 + 2 = 17 + 1 = 18
400
Independence
What is SLR?
400
An analysis of Age (in years) versus Total Weekly Purchases (dollars) generates the linear model of Predicted Purchases = 539.803 + 1.103Age. Is the y-intercept meaningful?
What is No, a zero year old person cannot make purchases.
400
With the additive ANOVA model, you report the ______ effects. With the interaction/factorial model, you report the _______ effects?
What is Main, Treatment?
400
p-value
What is the probability of observing the test statistic we obtained (or higher) by random chance?
500
You obtain the following results for a Two-Way ANOVA. What can you conclude about the main effects for each explanatory variable and the interaction term? Political Affiliation: F(3,68) = 2.65, p >.05, Ethical Orientation: F(3, 68) = 5.45, P <.05, & Interaction: F(3, 68) = 6.87, p <.05
What is There is a significant interaction and main effect of ethical orientation but there is not a significant effect of political affiliation?
500
Random Sample
What is ANOVA?
500
A person tells you their Math SAT score was 500. Predict their Verbal score using the linear model of Predicted Verbal SAT Score = 171.333 + 0.6943Math SAT Score.
What is 518.483
500
Least Squares
What is A method that minimizes residuals to obtain a linear line of best fit for 2 quantitative variables
500
Parameter
What is a summary value describing a population?
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