WGU D465 DATA APPLICATIONS OA EXAM ACTUAL
QUESTIONS AND ANSWERS| LATEST
R and Python similarities
Both widely used in data science with extensive libraries.
R unique challenges
Steeper learning curve, limited web dev capabilities.
Advantage of storing code in R
Allows reproducibility and collaboration among analysts.
Programming languages and use cases
Python: web dev, data science, ML, automation.
MIN function in spreadsheets
Returns the smallest value in a cell range.
COUNTIF function in spreadsheets
Counts cells meeting a specified condition.
Pivot table elements
,Rows, columns, values, filters for data aggregation.
SELECT command in SQL
Retrieves data from one or more database tables.
JOIN commands in SQL
INNER, LEFT, RIGHT, FULL OUTER JOIN types.
Delimiter for code chunks
Triple backticks or markup to define code sections.
Output formats for documents
HTML, PDF, Word (docx), Markdown.
Presentation formats
Slides, Dashboards, Interactive web apps.
Knit button in R
Compiles R Markdown into desired output formats.
Symbol for comments in R
Pound sign (`#`) precedes comments in R.
,Nested function usage
Simplifies operations, improves code readability.
Logical operators
AND (&&), OR (||), NOT (!).
Advantage of tidyverse
Cohesive data manipulation packages in R.
Functions in ggplot2
ggplot(), geom_point(), geom_line(), aes().
Plus sign in ggplot2
Adds layers to ggplot objects for customization.
Common errors in ggplot2
Incorrect aesthetic mappings, syntax misunderstanding.
Basic aesthetic attributes in ggplot2
x-axis, y-axis, color for plot customization.
, Smoothing line usage
Visual representation of trends in data.
dplyr filter() function
Subset rows based on specific conditions in R.
VLOOKUP function in spreadsheets
Searches for values in a vertical column.
Locking table array in VLOOKUP
Prevents range changes for formula accuracy.
Different JOIN functions in SQL
INNER, LEFT, RIGHT, FULL OUTER JOIN types.
COUNT vs. COUNT DISTINCT in SQL
QUESTIONS AND ANSWERS| LATEST
R and Python similarities
Both widely used in data science with extensive libraries.
R unique challenges
Steeper learning curve, limited web dev capabilities.
Advantage of storing code in R
Allows reproducibility and collaboration among analysts.
Programming languages and use cases
Python: web dev, data science, ML, automation.
MIN function in spreadsheets
Returns the smallest value in a cell range.
COUNTIF function in spreadsheets
Counts cells meeting a specified condition.
Pivot table elements
,Rows, columns, values, filters for data aggregation.
SELECT command in SQL
Retrieves data from one or more database tables.
JOIN commands in SQL
INNER, LEFT, RIGHT, FULL OUTER JOIN types.
Delimiter for code chunks
Triple backticks or markup to define code sections.
Output formats for documents
HTML, PDF, Word (docx), Markdown.
Presentation formats
Slides, Dashboards, Interactive web apps.
Knit button in R
Compiles R Markdown into desired output formats.
Symbol for comments in R
Pound sign (`#`) precedes comments in R.
,Nested function usage
Simplifies operations, improves code readability.
Logical operators
AND (&&), OR (||), NOT (!).
Advantage of tidyverse
Cohesive data manipulation packages in R.
Functions in ggplot2
ggplot(), geom_point(), geom_line(), aes().
Plus sign in ggplot2
Adds layers to ggplot objects for customization.
Common errors in ggplot2
Incorrect aesthetic mappings, syntax misunderstanding.
Basic aesthetic attributes in ggplot2
x-axis, y-axis, color for plot customization.
, Smoothing line usage
Visual representation of trends in data.
dplyr filter() function
Subset rows based on specific conditions in R.
VLOOKUP function in spreadsheets
Searches for values in a vertical column.
Locking table array in VLOOKUP
Prevents range changes for formula accuracy.
Different JOIN functions in SQL
INNER, LEFT, RIGHT, FULL OUTER JOIN types.
COUNT vs. COUNT DISTINCT in SQL
