Visualization
How many variables are in plot number 1?
One
This statistic measures the difference between two group means relative to the variability within each group, assuming unequal variances. (Provide the name of the test as well)
The Test statistic for the Welch's t-test
A marketing manager wants to estimate the average satisfaction score of customers who bought a new product from their company. He randomly selects 100 customers and asks them to rate the product on a scale of 1 to 100.
One Population Mean - Confidence Interval
What is wrong with this statement? State the truth.
A p-value can be negative.
The p-value is between 0 and 1.
Who is the president of Cal Poly?
Armstrong
How many variables are in plot number 2?
Two
This is the name of the statistic that measures the proportion of variation in the response variable that is explained by the predictor variable in a simple linear regression model.
R-Squared
A human resources manager wants to compare the productivity of employees before and after a training program. He measures the number of tasks completed by each employee in a week before and after the training. He uses this technique to test if there is a significant difference in the mean productivity of employees after the training.
Paired t-test
What is wrong with this statement? State the truth.
The null hypothesis for simple linear regression is that there is a linear relationship between the explanatory and response variables.
The null hypothesis for simple linear regression is that there is *NOT*a linear relationship between the explanatory and response variables.
What is the Capitol of California?
Sacramento
What are the variables in plot number 2?
Region and Sales
This is the name of the interval that estimates the range of possible values for a single new observation given a specified level of confidence.
Prediction Interval
A sales manager wants to compare the average sales revenue of four different regions in a quarter. He randomly selects 20 sales representatives from each region and records their sales revenue. He uses this technique to test if there is a significant difference in the mean sales revenue among the four regions.
One-Way ANOVA
What is wrong with this statement? State the truth.
As the level of confidence increases, the confidence interval decreases.
As the level of confidence increases, the confidence interval increases.
What is Dr. Williams's Wife's name?
Kelley
State and explain the relationship between the explanatory and response variables in plot 4.
1) Sales and Profit
2) Positive
This is the name of the interval that estimates the range of possible values for the mean response of a population given a specified level of confidence.
Confidence mean interval
(Not on Quiz) A quality control manager wants to compare the effect of two factors (temperature and pressure) on the defect rate of a manufacturing process. He randomly assigns 15 batches of products to each of the four combinations of temperature (high or low) and pressure (high or low) and measures the defect rate of each batch.
How many variables are here? What are they?
3
Pressure, Temperature, and Defect Rate
What is wrong with this statement? State the truth.
Type I error is failing to reject the null hypothesis when the null hypothesis is false.
Type I error is rejecting the null hypothesis when the null hypothesis is true.
What does Dr. Williams prefer, statistics or programming?
Both
How many variables are in plot 4? What are they?
Profit, Sales, and Region
If the standard deviation of residuals is not 0, is it possible for the correlation to be -1 or 1. Explain
The only want standard deviation of residuals is 0, is if every point is on the regression line which implies r is equal to 1 or -1.
(Not On Quiz) A quality control manager wants to compare the effect of two factors (temperature and pressure) on the defect rate of a manufacturing process. He randomly assigns 15 batches of products to each of the four combinations of temperature (high or low) and pressure (high or low) and measures the defect rate of each batch. He uses this technique to test if there is a significant interaction effect between temperature and pressure on the defect rate.
Two-Way ANOVA
What is wrong with this statement? State the truth.
A confidence mean interval creates an interval of plausible values for the slope parameter.
A confidence mean interval creates an interval of plausible values for a predicted mean response value.
Which 4 countries is Dr. Williams visiting this summer?
Italy, Portugal, France, and Canada