Sort, filter, slice, pivot, and graph using a Tableau Public, a free version of the market leading visualization tool.
Combine multiple data sources using joins, blends, unions, and relationships.
Create bar charts, pie charts, and line graphs.
Create calculated fields with conditional logic.
Map your data to quickly detect geographic variation.
Create a dynamic dashboards combining multiple worksheets.
Create trendlines and understand the relevant statistical metrics such as p-value and R-squared.
Create forecasts with prediction intervals, accounting for seasonal variability.
Take two full-length practice exams for the Tableau Desktop Certified Associate Exam.
Use publicly available data to create visualizations on topics that interest you - anything from the economy to the Olympics.
- [Instructor] Trend lines
in Tableau. A trend line, also called
a best fit line, explains the relationship
between two or more variables. For example, for every dollar in
sales, how many dollars in profit do we receive? To see that, I'm going to add
both profit and sales to the view. And now, I'm only getting a
single point on my scatter plot. If I want to fix that, go to
analysis and remove the aggregate measures, so that,
instead of seeing a single aggregate value for sales
and profit, I see each individual order as
a different point on my scatter plot. And so, it looks like, roughly,
as sales increases, probably profit also increase,
but we can see it much more clearly what the relationship is
if we use a trend line. So, I'm going to drag this over
to linear and now, I get, basically, an equation
that tells me how sales and profit relate to each other. And this basically says that for
every one dollar of sales, on average, I have an additional
14 cents of profit. The intercept is 3.6. So, for example, if I had 100
dollars sales, this tells me that I'd have
100 times 14 cents. So that would be 14 dollars plus
3.6, so that would be another $3.60. So, think maybe about
18 dollars in profit, if I had 100 dollars sales. This is not an exact
relationship, this is just describing what the average
relationship is between profit and sales. We can also model more complex
relationships. If I go back to trend line,
click on it again and I could do a logarithmic
relationship. So now, this is showing profit
in terms of the log of sales. Or I could do,
if I choose trend line, the exponential, and so, this is
showing the log of profit in terms of sales. Or I could do a polynomial,
and this is showing profit in terms of sales cubed,
sales squared and sales to the first power. Or if I wanted to make it a
second degree polynomial, I could use this,
click OK. And now I get an equation with
profit in terms of sales squared times sales to the first power. So that is an introduction to
trend lines in Tableau. There's a little bit more to
say about it, so I will create another video
that goes into a little bit more detail but that's
an introduction. Let me know if you have any
questions and thank you.