unit 3
how to create a bullet graph?
- create a side by side bar char - remove the dimension and one measure - move a measure into columns - right click axis and click add reference line per cell - add distrubtion areas to show progress - right click column axis and click add reference line - distribution per cell = value = 50, 75, 100 (this is how you want the distribution to be marked so when one item gets to the 50% mark, etc.
what to ask to determine whether to use a scatter plot?
- see whether the measure increases or decreases with changes in another measure - whether a change to one measure has an effect on another measure and what that change is - how closely a measure follows the changes to another measure
maximum number of columns and rows in a text table?
16 columns and 50 rows
how many measure values and names do you need for them to show up?
2+
no correlation
There is no relationship between data sets.
add sums
analysis menu -> total
measure names
appears at the bottom of the Dimensions area in the Data pane and contains the names of all measures in your data, collected into a single field with discrete values - category of dimensions
measure values
appears at the bottom of the Measures ares in the Data pane and contains all the measures in you data, collected into a single filed with continuous values. - values in measure fields, all of the measures
negative correlation
as one variable increases, the other decreases - it goes lower on the y axis as it goes longer on the x axis
what is a bullet graph?
bar chart with a vertical line showing where one measure is.
what are bar in bar charts?
bar within a bar chart
when would you create calculated fields in a bullet graph?
based on whether a measure has met or exceeded target • Create calculated fields so users can read the view not just infer
when do density maps work best?
better when the location is a limited space - such as addresses and addresses that constantly change
how to create a side by side bar chart?
put your dimensions and 1 measure in the rows and columns shelves. Drop the other measure into the axis for the remaining measure ◦ Put measure names on the same shelf as the dimensions so it creates 2 seperate rows of bars of the measures
what does correlation show?
relationship between two variables - a relationship exists but it does not mean one causes the other
to make dual axis be on the same axis, what do you do?
right click right axis and click synchronize axis
how to easily add a text table
right click tab name -> show as crosstab
how to add annotations for an outlier
right click the outlier mark -> annotate -> mark -> edit annotation
where is latitude in density maps?
rows
what does no correlation show?
scatter points are all over
what do density maps show?
show trends in location but are a lot better with showing them when there's more data points to show.
what are filled maps good for?
showing ratio data
what are text tables good for?
showing specific values - good for brainstorming - showing accuracy
what is text tables not good for?
showing trends
how to get rid of unknown locations?
special values indicator -> edit locations -> click unrecognized cells -> start typing where the actual location is
where does negative correlation start/trend?
starts at a high value and trends lower
where does positive correlation start/trend?
starts at low values and trends higher
subtotals
summary functions applied to part of a data range - shows subtotal for each outer dimensions
filled maps
the color that fills the area can be used to encode values of measures or dimensions ◦ Color represents the regions
what does a density map show?
the frequency of marks in an area ◦ Shows the amount of overlapping mark in an area
when do you use correlation?
to answer questions about the data
clusters
well defined groups of marks
what does distribution in a bullet graph show?
whether a measure has gotten to 50, 75, 100%
what to ask about outliers?
why it happened? was it a mistake? do you need it? if not, exclude it
can you choose which measure values to show?
yes
do density maps use latitude and longitude?
yes
what are filled maps comparing?
you're not comparing a measure by size, just color
what do filled maps need?
‣ Quantitative or qualitative (dimensions or measures)
what do symbol maps need?
‣ Quantitative values or measures ‣ Geographic data
how to change ambiguous countries?
◦ Change this by going to map -> edit locations -> click ambiguous cell -> specify the country/state/city to specify where these are
are longitude rows or columns in filled maps?
◦ Columns
advantages of a bar in bar chart?
◦ More immediate understanding of the data
are latitude rows or columns in filled maps?
◦ Rows
is longitude rows or columns in symbol maps?
◦ Rows
questions to ask to see whether to build a highlight table?
◦ specific values in the data? ◦ Identifying patterns or outliers within the context of the entire dataset? ◦ Is the color for patterns or ourliers sufficient to achieve the visualization goals?
if you have a measure for a scatter plot, how many points will it show?
one but it will add more as you add more dimensions
what are highlight patterns good for?
pointing out data patterns
what do bullet graphs show?
progress towards a fixed goal
text tables
1. encodes words and numbers and arranges them in columns and rows 2. used to display simple relationships between quantitative values and corresponding categorical subdivisions 3. ideal for looking p and comparing individual values - tabular
how to create a bar in bar chart?
1.) bring in a dimension and a measure 2.) drag a measure to the left axis (creates two bar icon new mouse) 3.) then drag measure names over to color 4.) turn stag bars off 5.) drag measure names to size - ◦ Have 2 measures in a bar chart - Move one measure to colors ◦ Analysis drop down menu -> stack marks -> off ◦ Control click and drag the measure to size to change the size of one of the bars so you can see where one of the bars
positive correlation
A correlation where as one variable increases, the other also increases, or as one decreases so does the other. Both variables move in the same direction. - it goes higher on the y axis as it goes longer on the x axis
scatter plot
A graph with points plotted to show a possible relationship between two sets of data. - shows 2 measures and patterns
correlation
A measure of the extent to which two factors vary together, and thus of how well either factor predicts the other. - statistical relationship between values
dual axis
A type of chart used to plot more than one data series using a second axis. - having 2 charts in one area and axis which compares 2 measures on the same axis
outliers
Numbers that are much greater or much less than the other numbers in the set - data points which are away from the trend - diverge from a trend
highlight tables
color encoded crosstabs. Call attention to very high or low data values and are useful for showing detailed values in text, while emphasizing outliers and patters in color - highlight values of importance or trends
are latitude rows or columns in symbol maps?
columns
where is longitude in density maps?
columns
how do bullet graphs work?
compares 2 measures by showing the bar chart in one measure and the vertical line in another measure
what are symbol maps good for?
comparing measures as the size and color of the marks will differ
what are bar in bar charts good for?
comparing measures directly
what do scatter plots show?
correlation; The relationship between two variables. They are often used as follow-ups to a cause-and-effect analysis - they show trends and outliers
how to make it a dual axis?
down arrow -> dual axis
how to create a highlight table?
drag the measure to the colors, change the marks type to square - this treats every cell its own mark
what group of people wlould you most likely use text tables for?
financial analysts
geographic data
information that identifies the geographic location of features and boundaries on earth (natural and constructed) - data that describes a physical location - longitude vs latitude
what do symbol maps work best with?
large amounts of data
symbol maps
marks are shapes or symbols placed at specific geographic locations - ◦ Symbols to represent a point of a region
what are the names of the 2 fields that tableau creates that dont exist in the data source?
measure values, measure names
is it better to add more or less marks to a density map?
more
can you use city in a filled map?
no
