Any statistician or math wiz or excel gurus? Need help w/ data charting.

Hi,

I was wondering if there were any gurus that could help me w/ something.

I wanted to plot data points in excel and generate a chart. For example a 12- month rolling average of some sort.

More so, when people say seasonally adjusted, how would you adjust the data? For example, job numbers, and holidays being temporary jobs, how would you remove it?

Thanks

 

You can find one by posting an ad in your local University's campus newspaper. Pay them $8/hr and they will flock to you.

 

Seasonal adjustment software from the census: http://www.census.gov/srd/www/x12a/

This uses something called auto-regressive integrated moving average. This is used all over the world by all kinds of institutions to do seasonal adjustments, and it's completely free.
I tried it a while back for someone else, seems to work OK. You have to read the manuals carefully to get anywhere, not the most user-friendly package in the world. But as I recall, once you get to the point where you're able to use it, it outputs some pretty neat graphs and such.

 

I would have to buy the software?

 

The question I have is, what exactly is seasonally adjustment in a time series? What is removed?

Is creating a simple average in excel hard? I've been using the excel tutorials and trying to chart housing prices for the year on a chart and show an average.

GOsh, I hate statistics. ugh.

 

Just use the Average function. If your time series is in Column A and you want a 3 period MA, insert a formula into Cell B3 that says "=AVERAGE(A1:A3)".

You can then copy/paste that formula down all of Column B to create a rolling moving average.

 

Quoting from myself: "...and it's free."
Just click on the link.

 

if you're still at the point of asking "Is creating a simple average in excel hard" you are wasting your time.

better you find existing charts and use them

 

To simplify, I have a lemonade stand w/ yellow, white, pink versions for the year.
jan2011 - 3 White, 3 pink, 1 Yellow

etc etc

I have already plotted the points on a line chart, but wanted to use the trendline function, but was stuck w/ the MOVING AVERAGE PERIOD PART.

What are they referencing when it comes to period? How can I throw in a moving average?

 

Not bad, I managed to get the function working.


I guess my question is, how would you folks chart qtr to qtr change?

Would you take average of jan,feb, march vs apr, may june average? or just end of march and june balance?