DATA LITERACY EXAM QUESTIONS AND ANSWERS #5
Which graphs are more trusted - correct answer beautiful
Features of plots - correct answer title, x-axis & y-axis (values, label), legend, data
points/line/bars
Pie chart - correct answer shows proportions of different categorical and mutually-
exclusive options
Proportions need to add up to 1 (100%)
Bar plots - correct answer to compare values associated with separate (usually
categorical) variables
Can be vertical or horizontal
Can quickly become overwhelming if too many categories
Important to include error bars if the height of the bar is an average
Depending on circumstance, it may be better to plot individual data points
Line graphs - correct answer only appropriate when x values are continuous
Frequently used for time-series data
Can involve 2 y-axes (w caution)
Can have error bars/bands
Use lines only to connect sequential data, missing data points should not be
represented with lines
Scatter plots - correct answer shows every data point
Can help show relationships b/w variables while looking at all the data
Could easily be overwhelming
Histograms - correct answer bar plots specifically that plot frequency
No gaps between bins
Number ranges
, Bin widths - correct answer plot shapes and readability can depend extensively on bin
widths
Guidelines for good plots - correct answer clean presentation
Logical representation
Make all plot elements clearly visible
Label your axes
Sufficiently large font
No unnecessary color
Include a title (if useful)
Include a legend (if necess.)
Avoid clutter
What should not do with axes - correct answer do not invert them - upwards = increase
Axes/legend should not change midway
Colors shouldn't mean diff things
Truncating axis - correct answer don't truncate axes when you want to show absolute
magnitude
Truncating axes can sometimes exaggerate relative diff
Sometimes okay to truncate axis to the reasonable range for a measure (especially
when relative magnitude matters)
Truncating axes especially okay when want to show change over time
Colors - correct answer use appropriate colors
Use basic elements of color for representation
- hue: useful for comparing categories that are not ordered
Chroma / value (saturation/brightness): useful for ordered relationships
Magnitude = light to dark shade
Categorical = diff colors
Consider audience (color blind)
Aspect ratio - correct answer ratio of width to height
Widening the x axis makes the slope look steeper, implying a greater increase
Elongating the width/height can affect interpretation
Including all necessary info - correct answer need to balance amount of info
Mean and standard deviation across subjects
But keep it simple
Which graphs are more trusted - correct answer beautiful
Features of plots - correct answer title, x-axis & y-axis (values, label), legend, data
points/line/bars
Pie chart - correct answer shows proportions of different categorical and mutually-
exclusive options
Proportions need to add up to 1 (100%)
Bar plots - correct answer to compare values associated with separate (usually
categorical) variables
Can be vertical or horizontal
Can quickly become overwhelming if too many categories
Important to include error bars if the height of the bar is an average
Depending on circumstance, it may be better to plot individual data points
Line graphs - correct answer only appropriate when x values are continuous
Frequently used for time-series data
Can involve 2 y-axes (w caution)
Can have error bars/bands
Use lines only to connect sequential data, missing data points should not be
represented with lines
Scatter plots - correct answer shows every data point
Can help show relationships b/w variables while looking at all the data
Could easily be overwhelming
Histograms - correct answer bar plots specifically that plot frequency
No gaps between bins
Number ranges
, Bin widths - correct answer plot shapes and readability can depend extensively on bin
widths
Guidelines for good plots - correct answer clean presentation
Logical representation
Make all plot elements clearly visible
Label your axes
Sufficiently large font
No unnecessary color
Include a title (if useful)
Include a legend (if necess.)
Avoid clutter
What should not do with axes - correct answer do not invert them - upwards = increase
Axes/legend should not change midway
Colors shouldn't mean diff things
Truncating axis - correct answer don't truncate axes when you want to show absolute
magnitude
Truncating axes can sometimes exaggerate relative diff
Sometimes okay to truncate axis to the reasonable range for a measure (especially
when relative magnitude matters)
Truncating axes especially okay when want to show change over time
Colors - correct answer use appropriate colors
Use basic elements of color for representation
- hue: useful for comparing categories that are not ordered
Chroma / value (saturation/brightness): useful for ordered relationships
Magnitude = light to dark shade
Categorical = diff colors
Consider audience (color blind)
Aspect ratio - correct answer ratio of width to height
Widening the x axis makes the slope look steeper, implying a greater increase
Elongating the width/height can affect interpretation
Including all necessary info - correct answer need to balance amount of info
Mean and standard deviation across subjects
But keep it simple
