07-07-2015 01:33 PM
I am looking for a way in sas to look at component changes over time.
- data set that contains material_used quantities with date from 2011-2015
data set looks like this:
Unit#, Date, Part#, Qty_used
345 01jan2014 5d3423 5
2034 23feb2015 6t5453 10
to many years of data
- data set that contains Expected 2015 usage(but is total for the year)
dataset looks like
Year, Part#, Expected_Qty_used
2015 5d3423 400
2015 6t5453 700
I would like to take the trend data by month from the first data set and then figure out from previous usages how many i think i should use in the current year based on the previous years.
Is there a tool or method in sas that could do this for me?
If not are there any suggestions on how i go about this?
07-07-2015 01:43 PM
I have a start here but I'm not sure what you are trying to do.
infile cards dsd;
informat date date9.;
format date date9.;
input Unit$ Date Part$ Qty_used ;
infile cards dsd;
input Year Part$ Expected_Qty_used;
create table start as
from have a left join
have2 b on
a.part = b.part;
07-07-2015 01:52 PM
Sorry I know i am not explaining this well. Let me try again.
From my first data set there is many years and about a million records. I want to figure out from all that previous history by part number and month an average trend across the year. I then want to use that trend to change my second data set from a yearly total into a monthly trend based on past history of that part. I need to do that so I can compare my expected usage to my actual usage and account for the trends of previous history.
I hope this helps
07-07-2015 02:10 PM
I think you need to provide an example of what you expect the final output to look like.
I can't tell if you are trying to run a regression to forecast or to partition an annual total into monthly components.
Do any of your part usages have an actual seasonality such as a use of snow-blower parts which might tend to be used in winter or some such? If so you are likely looking at something from the SAS/ETS module and the project will go much better using those tools.
Likely the first step would be to summarize your part usage to a monthly level which might be something like:
proc summary data=material_used nway;
class partNumber date;
output out=MonthTotals (drop=_type_) sum=;
format date YYMON7. ;
07-07-2015 03:30 PM
Yes many parts do have actual seasonality. Is there a statistical test that can be used to Validate this?
Output i am looking for would look like this
Total expected for 2015 based on past trends
So basically I need to take a 1 year estimated Number and generate the properly weighted values by month based on the past trend data. This i hope will allow me to see if I am out of the box on the estimated numbers early in the year. I am not a statistician but do have a good understanding of sas programing and I am really looking for Ideas on what tools i need and the process to go through to get to this end result.
Thank you so much for all your time.
07-07-2015 04:25 PM
I think you might want to move this to the Forecasting area as this bit of data looks seasonal to me ant the Time Series procedures, which I don't have access to, as part of SAS/ETS look much more likely to be helpful.
Without ETS, if, and this is a big if, you have enough years of data you might run a regression by part and month with year as the independent variable. It wouldn't be very sensitive though and unless the trends are pretty consistent not very precise.