topic Re: Visual Forecasting Events in SAS Forecasting and Econometrics

Visual Forecasting Events

Ghabek — Mon, 29 Jun 2020 21:33:28 GMT

Hello

Im in VIYA visual forecasting 8.4 and using a dataset to forecast shipments during covid time - data is form Jan-Jun2020 weekly and I want to inject covid events called

covidonset and covidpeak using the code form users guide of VF......Im attaching the sas program here and sample of the dataset used to forecast....I get an error in pipeline saying the name of the event field needs to be CHAR but it is.....dont know what is going on.....

any help to get it working in VF would be appreciated

Re: Visual Forecasting Events

solarflare — Tue, 30 Jun 2020 14:17:25 GMT

Hi Ghabek,

I noticed your covid.sas file is missing a semicolon on the last line.

Try fixing that and rerunning it. I was able to create the event table on VF 8.5 after that.

Re: Visual Forecasting Events

Ghabek — Tue, 30 Jun 2020 14:20:39 GMT

i fixed that but i get the error I sent you in the screen shot for the
event table column not being char......anyway we can hop on call quick?

Re: Visual Forecasting Events

solarflare — Tue, 30 Jun 2020 14:24:25 GMT

hmm, let me investigate a little more first. I'm less familiar with changes in events between 8.4 and 8.5.

Re: Visual Forecasting Events

Ghabek — Tue, 30 Jun 2020 14:26:39 GMT

this is the error o get in pipeline for autoforecasting

[image: image.png]

Re: Visual Forecasting Events

TammyJackson — Tue, 30 Jun 2020 14:59:44 GMT

I can't see the image.

Re: Visual Forecasting Events

Ghabek — Tue, 30 Jun 2020 15:02:39 GMT

here is the log file.....

Re: Visual Forecasting Events

TammyJackson — Tue, 30 Jun 2020 15:17:19 GMT

I can't see the log file, either.

You might find this article helpful:

https://communities.sas.com/t5/SAS-Communities-Library/Improve-Accuracy-by-Adding-Events-in-SAS-Visual-Forecasting-8-5/ta-p/649435

Re: Visual Forecasting Events

Ghabek — Tue, 30 Jun 2020 15:17:38 GMT

i mainly want to prepare the forecast for a second covid wave in Aug and Sep....do i need to create a new event var called covidwave2 from Aug-sep30??

my data ends Jun 8......

thanks

Re: Visual Forecasting Events

Ghabek — Tue, 30 Jun 2020 15:21:17 GMT

here is the log file......

cant attach it...can i have your email and i can send it?

im a sas partner

Re: Visual Forecasting Events

TammyJackson — Tue, 30 Jun 2020 17:47:17 GMT

So an event produces a dummy variable that models an effect such as an outlier, level shift or ramp. Modeling the effect improves the model. Often the event is modeled separately, and then the seasonality and the trend are easier to model once the event effect is removed. If an event occurs in history and in forecast, then the impact of the event on history can be used to forecast the future effect of the event. I would suggest first trying to determine the historical effect. Is that effect a temporary level shift? a ramp? You can try different effects, different dates, or even several different effects and then combine the effects. Once you know the historical impact, you might be able to guess better what the future impact will be.

Re: Visual Forecasting Events

TammyJackson — Tue, 30 Jun 2020 17:49:13 GMT

In order to use the information obtained from the historical effect on the forecast, you would just use a single event with some timing values (dates or datetimes) in the historical period and some in the forecast period.