CFA Level I · CFA Level I Exam · Introduction to Financial Data Science
A model predicting loan defaults achieves very low error on the training data but performs poorly on new data. This outcome is best described as:
This is best described as overfitting caused by excessive model complexity. The model has captured noise in the training data rather than the true underlying relationship, so it generalizes poorly to new data. Underfitting would instead produce weak results on training data as well.
- Aunderfitting caused by too few features
- Boverfitting caused by excessive model complexityCorrect
- Cdata leakage caused by a smaller validation sample
Explanation
Low training error with poor out-of-sample performance is the signature of overfitting: the model has learned noise specific to the training set, usually from excessive complexity. Underfitting would show poor performance on both sets. The third option does not describe this pattern.
Did you get it right without looking?
One question tells you little. A timed set on Introduction to Financial Data Science shows your real accuracy, how long you take and where you lose marks.
More Introduction to Financial Data Science questions
- An analyst has the following values for a feature: 8, 10, 12, 14, 56. The analyst applies min-max normalization to the value 14. The normali…
- An analyst trains a model to predict whether a borrower will default, using historical loans that are each labeled "default" or "no default.…
- An analyst converts a set of earnings call transcripts into a form suitable for modeling. She removes punctuation, converts all letters to l…
- A data scientist wants to reduce the words "earned", "earning" and "earnings" to a common base form, using a rule-based procedure that strip…
- A fund uses a model that classifies firms as likely to default or not, using labeled historical data on past defaults and firm characteristi…
- An analyst preparing unstructured text from analyst reports for natural language processing removes common words such as "the", "is" and "an…