Exam PA 2.0 Questions And Answers 2026
Update!!!
Data needs to be unbiased and representative of the population
What should be true for data to be considered relevant?
and time frame of interest
Data values should be reasonable in the business context, have
What makes data high quality?
consistent units and rules, and sufficient documentation
Structured data This is data that can fit into a tabular arrangement
Structured data is easier to manipulate but cannot represent data
Structured data pros and cons
that can’t naturally fit in a tabular arrangement
Data that cannot fit into a tabular arrangement, such as audio,
Unstructured Data
images, etc.
This data is more flexible but harder to access and include in a
Unstructured data pros and cons
predictive model
This is information that can be used to trace to an individual’s
Personally Identifiable Information
identity
de-identify data to remove personally identifiable information,
How can personally identifiable information be handled? ensure data receives sufficient encryption, and conduct model
operations while following terms of use
These are variables that may be significant but using them in a
Sensitive variables
model may lead to legal, fairness, and discrimination concerns
This occurs when a predictor in a model leaks information about
Target leakage
the target variable that is not available at the time of modeling
Predictor variable is observed at the same time or after the target
How can you detect target leakage? variable, target variable is included in a predictor, target variable is
used in principal components, or target variable is used in clusters
Goals of Exploratory Data Analysis Validate data and generate insights for modeling
Clean data for inappropriate values, errors, and outliers so that data
What does it mean to validate data
is ready for analysis
Understand the characteristics of variables, identify potentially
What does it mean to generate insights for modeling useful predictors, generate new features, and decide which type of
model is best
Summary statistics are objective and comparable across variables,
Pros and cons of summary statistics but can only capture certain aspects of distributions and are easily
affected by outliers
Graphical displays provide visual impressions of a distribution and
can reveal information not easily captured by summary statistics,
Pros and cons of graphical displays
but are not as precise as summary statistics and less comparable
across variables
Three types of bivariate graphical displays for categorical variables Stacked bar charts, dodged bar charts, and filled bar charts
, When to use bar charts To display counts of levels in a categorical variable
When you want to display proportions of levels in a categorical
When to use filled bar chart
variable. This loses information of the count of each levels
Update!!!
Data needs to be unbiased and representative of the population
What should be true for data to be considered relevant?
and time frame of interest
Data values should be reasonable in the business context, have
What makes data high quality?
consistent units and rules, and sufficient documentation
Structured data This is data that can fit into a tabular arrangement
Structured data is easier to manipulate but cannot represent data
Structured data pros and cons
that can’t naturally fit in a tabular arrangement
Data that cannot fit into a tabular arrangement, such as audio,
Unstructured Data
images, etc.
This data is more flexible but harder to access and include in a
Unstructured data pros and cons
predictive model
This is information that can be used to trace to an individual’s
Personally Identifiable Information
identity
de-identify data to remove personally identifiable information,
How can personally identifiable information be handled? ensure data receives sufficient encryption, and conduct model
operations while following terms of use
These are variables that may be significant but using them in a
Sensitive variables
model may lead to legal, fairness, and discrimination concerns
This occurs when a predictor in a model leaks information about
Target leakage
the target variable that is not available at the time of modeling
Predictor variable is observed at the same time or after the target
How can you detect target leakage? variable, target variable is included in a predictor, target variable is
used in principal components, or target variable is used in clusters
Goals of Exploratory Data Analysis Validate data and generate insights for modeling
Clean data for inappropriate values, errors, and outliers so that data
What does it mean to validate data
is ready for analysis
Understand the characteristics of variables, identify potentially
What does it mean to generate insights for modeling useful predictors, generate new features, and decide which type of
model is best
Summary statistics are objective and comparable across variables,
Pros and cons of summary statistics but can only capture certain aspects of distributions and are easily
affected by outliers
Graphical displays provide visual impressions of a distribution and
can reveal information not easily captured by summary statistics,
Pros and cons of graphical displays
but are not as precise as summary statistics and less comparable
across variables
Three types of bivariate graphical displays for categorical variables Stacked bar charts, dodged bar charts, and filled bar charts
, When to use bar charts To display counts of levels in a categorical variable
When you want to display proportions of levels in a categorical
When to use filled bar chart
variable. This loses information of the count of each levels
