Hi all,
I want to add confidence intervals to each point in a scatter plot/bar graph.
My data set:
A few thousand recent jeopardy games, each with the day of the week, total number of correctly answered questions, and total number of incorrectly answered questions
My chart: bottom right on this dashboard. Day of the week on the X, and # right and wrong on a dual Y axis.
The problem: When I drag the average with 95% confidence interval to the "cell", all that appears is the average. The band showing the confidence interval doesn't exist.
Attempted solution: I have manually calculated upper and lower bounds for the confidence interval for each column and input them as parameters. However, I cannot seem to add those bands to one column at a time -- instead, I end up with overlapping bands that cover everything from Monday to Friday. I imagine there's a work-around here, but it still seems needlessly complicated.. just hoping that someone can point me in the right direction to fix the built-in confidence interval.
Thank you!
@Keegan Barnes Even though the data set has many data points, the "Accuracy by Day" view only has one data point per weekday, which is not enough to calculate a confidence interval. (You could add [Game Id] to the view to fix this, but obviously that has drawbacks).
For the workaround mentioned, "manually calculated upper and lower bounds for the confidence interval for each column and input them as parameters," you can actually use calculated fields in Tableau to find the upper/lower CI values. For example:
AVG([Total Correct])+(1.96*(STDEV([Total Correct])/SQRT(COUNT([jeopardytable812.csv]))))
You can then add those calculated fields to Detail on the marks card to use them in reference lines. See Creating Error Bars or CI Bars
Please @ me in replies otherwise I won't receive a notification. Vote for more notification options
Hope this helps :)
What do you think of the new Community Forums? Let us know!
(Be sure to tag your ideas as 'community')
