TIBCO Spotfire Analytics and Statistics 2 — Questions and Answers
Question 1: What does the OVER function in Spotfire expressions allow you to compute?
- Loop over rows in a script
- Aggregations scoped to a specific set of columns (window/grouping context) (Correct answer)
- Filter rows dynamically
- Reference values from another table
Correct answer: Aggregations scoped to a specific set of columns (window/grouping context)
OVER performs an aggregation partitioned by specified columns, similar to SQL window functions, without collapsing rows.
Question 2: In Spotfire, what does the function 'Rank([Value]) OVER ([Category])' compute?
- Global rank of each value across the whole dataset
- Rank of each value within its category group (Correct answer)
- Percentile rank across all rows
- Alphabetical rank of the category
Correct answer: Rank of each value within its category group
Using OVER partitions the ranking by the specified category, so each group gets its own independent rank sequence.
Question 3: Which Spotfire function returns the value of a column from the previous row when data is ordered by a specific column?
- Lag (Correct answer)
- Previous
- Offset
- Prior
Correct answer: Lag
Lag retrieves the value from a preceding row by a specified offset, useful for period-over-period calculations.
Question 4: What is the purpose of the 'NodeId()' function in Spotfire's expression language?
- Returns the database primary key
- Returns the internal row index identifier for each row (Correct answer)
- Generates a unique UUID per row
- Returns the network node ID in a graph chart
Correct answer: Returns the internal row index identifier for each row
NodeId() returns Spotfire's internal zero-based row index, useful for uniquely identifying rows in expressions.
Question 5: In Spotfire, what does 'Correlation coefficient' as a trend line statistic measure?
- The slope of the regression line
- The strength and direction of the linear relationship between X and Y (Correct answer)
- The average prediction error
- The number of data points used in the fit
Correct answer: The strength and direction of the linear relationship between X and Y
The correlation coefficient (r) ranges from -1 to +1 and quantifies how strongly and in which direction two variables are linearly related.
Question 6: Which Spotfire feature enables running R or Python statistical models directly integrated with visualizations?
- Spotfire Macros
- TIBCO Enterprise Runtime for R (TERR) data functions (Correct answer)
- Spotfire Information Links
- Custom queries
Correct answer: TIBCO Enterprise Runtime for R (TERR) data functions
TERR (TIBCO Enterprise Runtime for R) allows R scripts to be embedded as data functions, processing Spotfire data and returning results back to visualizations.
TIBCO Spotfire Analytics and Statistics 2
What does the OVER function in Spotfire expressions allow you to compute?