Accelerate your Analytics Career
Answer these questions using the Superstore sample data.
Create a trend line for profit as a linear function of sales. What is the R^2 value?
Create a trend line for profit as a linear function of sales. According to the trend line, how much does profit increase for each dollar of sales?
Create a trend line for profit as a function of sales. Based on the R^2 value, which model type results in the best fit?
Be sure to click Submit Quiz to see your results!
Can someone explain why the answer for Q3 is Polunomial with degree two?
Different model type of trendlines have different shapes. I cannot paste picture here but you may google it.
For Q3, we want to know which model type best fits the data. The R-squared value will essentially tell us how close the data points are fitted to the regression line (closer to 0 means poor fit, closer to 1 means good fit), so all we need to do is compare the R-squared values between the different types of models and pick the highest one.
The R^2 represents how a model describe data. When setting the model as polynomial with 2 degree, the R^2 is around 0.156, which is the largest R^2 compared with other models.
Your email address will not be published. Required fields are marked *
Notify me of follow-up comments by email.
Notify me of new posts by email.
Specialist Practice Exam Data Analyst Practice Question PDF Specialist Practice Question PDF
Our online Tableau courses can help you get certified as a Data Analyst or Tableau Specialist.
Interested in learning Power BI? Check out the quizzes here.