HW 4

[Kartik Ramachandran]

My answers for Hw 4..let me know if you get anything different.

MA3    

MAD 55.44

MSE 5,522.66426180558 

MAPE 0.490406984 

MA7           

MAD 81.47285714 

MSE 9940.603038  

MAPE 0.721155834 

ES .5   

MAD 49.47165226 

MSE 4600.868401 

MAPE 0.437643252  

Thanks,

Kartik

[R. Thethy]

Do we need to do MA7? I thought we only have to do MA(3) forecasts and exponential smoothing forecasts with alpha=0.5?

But yes, I got the same answers.

Rajpreet

[Xiuya Li]

I got the same answer.

 

MA7 is not required from home work assignment. For MAPE I just used 0.0049 instead of 0.49%, I think it should be OK both ways.

 

Thanks!

Ted

On Wed, Apr 13, 2011 at 4:58 PM, Kartik Ramachandran <krama...@gmail.com> wrote:

[Ashish Swaroop]

Hi Everyone,

To calculate MAPE - we have to take Ft-Dt (prediction -actual )and not Dt-Ft. 

You should be getting some -ve values for MAPE.

My answers are - 

MA3

MAD 55.44

MSE 5522.63

MAPE -0.2764

Can you please check and let me know.

regds

Ashish

On Wed, Apr 13, 2011 at 4:58 PM, Kartik Ramachandran <krama...@gmail.com> wrote:

[Nicholas Woo]

I'm pretty sure everyone has been taking forecast - actual in order to come up with their MAPE results. It is impossible to have a negative result since you need to take the absolute value of the percentage change.

[Ashish Swaroop]

Ah...That's why.

I didn't take the absolute earlier.

thanks Nich

Ashish

[James Kim]

Hi Ashish,

I got the same answers as you for MSE = 5522.63.

On Apr 15, 2:42 pm, Ashish Swaroop <ashishswaroop2...@gmail.com>
wrote:

> Hi Everyone,
>
> To calculate MAPE - we have to take Ft-Dt (prediction -actual )and not
> Dt-Ft.
>
> You should be getting some -ve values for MAPE.
>
> My answers are -
>
> MA3
> MAD 55.44
> MSE 5522.63
> MAPE -0.2764
>
> Can you please check and let me know.
>
> regds
> Ashish
>
> On Wed, Apr 13, 2011 at 4:58 PM, Kartik Ramachandran

> <kramach1...@gmail.com>wrote:

>
>
>
>
>
>
>
> > My answers for Hw 4..let me know if you get anything different.
>

> >> *MA3    *
> >> *MAD 55.44*
> >> *MSE 5,522.66426180558 *
> >> *MAPE 0.490406984 *
> >> *
> >> *
> >> *MA7           *
> >> *MAD 81.47285714 *
> >> *MSE 9940.603038  *
> >> *MAPE 0.721155834 *
> >> *
> >> *
> >> *ES .5   *
> >> *MAD 49.47165226 *
> >> *MSE 4600.868401 *
> >> *MAPE 0.437643252  *
> >> *
> >> *
> >> *Thanks,*
> >> *Kartik*

[alex smirnov]

I got all the same answers

[Dinesh Kantaria]

Guys,

Just to make sure that when I calculate MAPE, the answer I got is same but it is in %, so my answers on

MA3

MAPE = 0.49%

And

ES (0.5)

MAPE = 0.44%

Please let me know if I have miss something.

Thanks,

Dinesh

[Crystal Diaz]

Dinesh,

I also have those same answers. My spreadsheet is attached if anyone wants to see the formulas.

Thanks!
Crystal

[Ajay Goyal]

how do you get the 11070 as the first forecast for ES.5?

[Rohit Gambhir]

Ajay,

   11070 is not to be used for forecast of E(.5 since it is for a date before Aug 10th. The problem needs us to compare only for data and forecasts starting from Aug 10th.

  My answers matches Crystal's.

  Thanks,
- Rohit Gambhir.