Spotfire Analytics and Statistics Flashcards

In TIBCO Spotfire, what does adding a 'Trend Line' to a scatter plot provide?

Answer: Fits a mathematical model (e.g., linear, polynomial) to show data trends

A trend line fits a regression model to the scatter plot data, visually indicating the overall direction and rate of change.

Which statistical curve type in Spotfire's trend line fits data that grows or decays exponentially?

Answer: Exponential

An exponential curve fits data where the rate of change is proportional to the current value, such as population growth.

What does Spotfire's 'Confidence interval' band around a trend line represent?

Answer: The uncertainty range within which the true regression line likely falls

The confidence interval band shows the range where the true mean response line falls with a specified probability (e.g., 95%).

In Spotfire, what does 'Prediction band' show on a trend line chart?

Answer: The range within which a new individual data observation is expected to fall

A prediction band is wider than a confidence interval and shows where individual future data points are expected to land.

What statistic does Spotfire display as R² on a trend line, and what does it indicate?

Answer: Coefficient of determination showing how much variance in Y is explained by X

R² (coefficient of determination) ranges from 0 to 1 and indicates what fraction of the dependent variable's variance the model explains.

In Spotfire, which aggregation method computes the middle value of a sorted dataset?

Answer: Median

Median returns the 50th percentile — the value at the midpoint of a sorted list, robust to outliers.