I know this is old, but like because of this channel, I was basically able to get 3.0 with a terror prof. For more context, the professor grades infamously low, but I still managed to get a score of 3.0, which is around 85%, or a B - B+.
Rightttt our professor literally makes it sound so much more difficult ..explaining such a simple thing for over 30 min when it can be shown for 5 minutes ..
The 4 weeks percentages were already convent to a percentage, that's why it adds up to 1. That's also why you divide the WMA by 5 for week 2. 3(x)/5 + 2(y)/5 = (3x+2y)/5 I think the important part to remember is to convert to percentages
Out class video... My exam will be conducted in a few hours I'm seeing this video all concept cleared. Thank you. God bless you dear. More n more shared in my class mates Whatsapp group
Thank you! 1. Is weighted moving average, or moving average really a forecasting method? Or is it a way of smoothing the data? (I am trying to learn and understand. ) 2. How do you determine which weight value to use? Thank you for the insight.
1. They are smoothing methods and can be used for forecasting. 2. Typically you choose your weights in a way that minimizes error. Methods used will vary by context.
I would suggest changing the values for weeks to a date structure. It makes it easier to follow. The term "next most recent" is an odd way to say the previous week
Correct me if I am wrong but for Forecast 5, the Numerator should read 3(45) + 2 (40), not 3 (45) + 2 (44) since we are using the last two most recent Sales (45 and 40). The answer 43 is correct though. Thanks by the way, you explain it so clearly!
@@joshemman normally if the instruction does not give a weighted value and youre asked to find the WMA for 2 periods, is it assumed its weighted by 1...so splitting the two periods by .6 and .4?
Well Explained, if i have the Data and i should put the weight values how i can calculate them ! i just have Data for sales last year and want to use this method it's applicable and how ! thank you very much for your support
Can we using the method for seasonal data where the irregularity can be extreme? For example, can we know that next week the sales would be 60, which is very different than the rest of your data?
Hello.. The video is great explained very clearly But I had a doubt, when "we assume the weights of different values the sum of their weights should be equal to 1", Here It is satisfied for 4week but not in case of 2week??
I have a small question on which basis should we consider the weights e.g. 2WMA we have picked 2,3. In 4WMA we have chosen 0,4 0,3 0,2 0,1 relatively. Is there a reseaon for choosing the weights? Can the column 4WMA values represent the upcoming year forecast?
The reason for choosing the weights can depend on the nature of the data, the objective of the forecast, and relevance of the recent data. But it is nothing to worry about unless you’re trying to choose your own weights. Yes! The 4WMA values are the forecast values.
@@joshemman Thanks a lot, this makes a lot of sense now :). I applied the method on 2021 to forecast 2022, the results are below the actuals I have in 2022 (Jan-Sep) Would you recommend more statistical methods to have more accurate results? I already have data for 2021 and 2022.
@@OmarAl93It depends on your data and your objective, Omar. Weighted moving average is usually applied to data that has no trend (not consistently increasing or decreasing). If there is trend, then regression might be a better approach.
Man, during 3:42, I think that something went wrong. So, for week 5 we should have to calculate (3*45+2*40)/5. 2*40 not 44. Because as seen all other calculations we have done it the first 2 CONSEQUENCE numbers from back to front.
if i increase number of weeks then error will decrease or increase. if error is increase as shown in ur example that 2wma give better smoothing than 4 wma then it means as number of periods increases the smoothing error get increased.
How about there is no given weight average but we need to calculate the three months and six montsh weighted moving averages?. Can someone help me/enlighten me please. THANK YOU
so finally there are 2 types of method if we got value 1 by calculating all given weight value so we have to have solve from 1st method if we are getting another value like 5 or 7 or 10 by calcuting so we have to do by the second method
@@joshemman I really don't know how to work out this equation. I'm doing an entrepreneurship course and I hate this part. The reason I said 0.50 cause you said assign the weight respectively to period 5 etc
how do you come up with weights of .4.3.2.1 for 4week Weighted average and for 2 week weighted average , how did u get Weights 3 and 2? is it an automatic assumption?
Hello! I got a question, I was reading about this method, and I saw that all the weights must be equal to 1, I'm a bit confused why did you choose weight 5 on the second example.
It's true that the total weight must be equal to 1, but he explains that even though his weight totals at 5, he divides his final answer by 5, so he gets the actual weight of one.
If the given weight equals to 1 means you don't have to dividw it by its n, then if the weight is not equal to 1 then you have to divide it by its n, right?
kindly solve this Ques ..it's taken from one of the prestigious competitive exam of India..so the Ques Is- given the numbers 2,6,1,5,3,7,2. if the weights used are 1,4,1 .then weighted moving average of order 3 are given by?.
2,6,1,5,3,7,2 with weights 1, 4, 1. The sum of the wights is 6. For weighted moving average of order 3, F4=(2+4*6+1)/6 = 4.5 F5=(6+4*1+5)/6 = 2.5 ... F8=(3+4*7+2)/6 = 5.5
the weights are decided by the management who conducted the study based on what they see is important. they are not fixed numbers, you could choose any weights you want. but generally managemnet or the person who is doing the forecasting give the recent data more priority than old data which means higher weights for rececnt data
Sir, I'm not exaggerating when I say you've saved my life. God bless you
Ndipo sukunama😂
I know this is old, but like because of this channel, I was basically able to get 3.0 with a terror prof. For more context, the professor grades infamously low, but I still managed to get a score of 3.0, which is around 85%, or a B - B+.
Thank you sir, this is very interesting
If only professors could be as clear as this video as well as Joshua's other videos. Thank you so much sir!
Rightttt our professor literally makes it sound so much more difficult ..explaining such a simple thing for over 30 min when it can be shown for 5 minutes ..
@@ivageorgieva2985 It's also why I believe actual experience is worth way more than knowledge for the most part.
Sir, I'm not exaggerating when I say you've saved my life. God bless you You Give me So much better than my teacher's explanation. Thanks! a lot
Glad to help Alehegn.
Thank you. You literally explained something that my professor couldn't for 2 straight hours. Thanks a lot.
The 4 weeks percentages were already convent to a percentage, that's why it adds up to 1.
That's also why you divide the WMA by 5 for week 2.
3(x)/5 + 2(y)/5 = (3x+2y)/5
I think the important part to remember is to convert to percentages
Saved me 5 hours of reading a complicated book. Thanks!
You are a better Professor than MY professor !!!! more clear and easy to understand!!! 100% GOOD for international students!
Thank you! I was so confused by this in my textbook. You broke it down to where I can understand the material!
lode ka textbook mai galat diya hai
sab loda bhenchod bakwaas hai
thank you sir, it took me 5 min to understand it clearly, u deserve everything in this world 😭🙌🏻
You have saved me! I've been stuck on a problem like this for hours!
Now I can pass my exam! Phew... Thank you for this. Very clear
Legit needed this vid. Thank you. If it wasn't for this vid I'd be stressed as hell.
Very helpful video. This channel must be located by students.
Given the following data, use exponential smoothing with α = 0.2 to develop a demand forecast for period 7. (Forecast for Period 1=10).
Out class video... My exam will be conducted in a few hours I'm seeing this video all concept cleared. Thank you. God bless you dear. More n more shared in my class mates Whatsapp group
Thank you!
1. Is weighted moving average, or moving average really a forecasting method? Or is it a way of smoothing the data?
(I am trying to learn and understand. )
2. How do you determine which weight value to use?
Thank you for the insight.
1. They are smoothing methods and can be used for forecasting.
2. Typically you choose your weights in a way that minimizes error. Methods used will vary by context.
Awesome job of breaking it down!
i just fall in love with your method of explaining🙈🙈🙈
Thank you so much 😀
I would suggest changing the values for weeks to a date structure. It makes it easier to follow. The term "next most recent" is an odd way to say the previous week
You're a legend! I wish my professor was like this :(
Your videos are amazing and really easy to understand, do you have anything about Simple Linear Regression?
Thanks for this simple and straightforward explanation.
I have a question on when do we use MSE vs MAE for error calculation
this was very helpful before I had to take an exam. Thank you!
Hello Joshua,I would like to thank you for wonderful explanation.i have a question will the smaller value of m will give good forecast if so then how.
Correct me if I am wrong but for Forecast 5, the Numerator should read 3(45) + 2 (40), not 3 (45) + 2 (44) since we are using the last two most recent Sales (45 and 40). The answer 43 is correct though. Thanks by the way, you explain it so clearly!
You're right. F5 should be (3(45) + 2 (40))/5 at 3:43. Thanks for pointing it out.
@@joshemman normally if the instruction does not give a weighted value and youre asked to find the WMA for 2 periods, is it assumed its weighted by 1...so splitting the two periods by .6 and .4?
@@rickyc1578 You should be given at least one weight.
Well Explained, if i have the Data and i should put the weight values how i can calculate them !
i just have Data for sales last year and want to use this method it's applicable and how !
thank you very much for your support
you are a great teacher sir everyone is a teacher but everyone is not have a Idea how to teach you teach very well sir
Can we using the method for seasonal data where the irregularity can be extreme? For example, can we know that next week the sales would be 60, which is very different than the rest of your data?
Thank you man tomorrow is my exam. It helped me. Great video.
#Weighted Moving Average 4WMA
weight = [0.4, 0.3, 0.2, 0.1]
sales = [39, 44, 40, 45, 38, 43, 39]
calc = lambda x: 0 if x < len(weight) else sales[x-1]*weight[0] + sales[x-2]*weight[1] + sales[x-3]*weight[2] + sales[x-4]*weight[3]
forecast = [ calc(x) for x in range(0, len(sales) ) ]
print(forecast)
Thank you sir! Your videos are clear and I always leave smarter than when I first arrived!
thank you very much for this video, why is 45 the most recent value to start?
Of all the recent periods, 45 is the closest the period we want to forecast.
Thank you. Which formula can I use in predicting the overhead budget.
Thanks again
This was very helpful. Thank you.
Glad it was helpful!
thank you so much this was really helpful, it was loud and clear...
You saved me.
Merci beaucoup!
Mister my question the instruction only weight moving average approch by your given example how to calculate?
Excellent explanation!
Thanks, Margaret.
Very good explanation
on what basis you calculated weights
thank you for your deeply help.
That was very comprehensible. Like it.
What is the benefit of taking Moving Averages?
How can we interpret MAD?
Hello.. The video is great explained very clearly
But I had a doubt, when "we assume the weights of different values the sum of their weights should be equal to 1", Here It is satisfied for 4week but not in case of 2week??
Because in 4 weeks the sum of weights are 1.
Because in 4 years week, the sum of weights is 1.
May the force be with you Joshua
What if we want to forecast more than one values in future. For example 21 future values in future? considering we have enough past data.
You cannot forecast more than one period into the future with this method.
How to find exp entail smoothing regression analysis, Markov chain, simulation. Thank you
Thank you for this, Sir!❤️
My pleasure, Ellisa!
Thank you very much, Sir for explaining well.
You are most welcome
I have a small question on which basis should we consider the weights e.g. 2WMA we have picked 2,3. In 4WMA we have chosen 0,4 0,3 0,2 0,1 relatively. Is there a reseaon for choosing the weights? Can the column 4WMA values represent the upcoming year forecast?
The reason for choosing the weights can depend on the nature of the data, the objective of the forecast, and relevance of the recent data. But it is nothing to worry about unless you’re trying to choose your own weights.
Yes! The 4WMA values are the forecast values.
@@joshemman Thanks a lot, this makes a lot of sense now :). I applied the method on 2021 to forecast 2022, the results are below the actuals I have in 2022 (Jan-Sep) Would you recommend more statistical methods to have more accurate results? I already have data for 2021 and 2022.
@@OmarAl93It depends on your data and your objective, Omar. Weighted moving average is usually applied to data that has no trend (not consistently increasing or decreasing). If there is trend, then regression might be a better approach.
Thank you so much for the videos. But I’m wondering if we could calculate week 8-10? how could I do that?
No, you cannot. You can only forecast one period into the future using this method.
thank you for the explanation. this was soo easy to understand.
Man,
during 3:42, I think that something went wrong. So, for week 5 we should have to calculate (3*45+2*40)/5. 2*40 not 44. Because as seen all other calculations we have done it the first 2 CONSEQUENCE numbers from back to front.
You're right. That was a typo. The answer is correct though.
Sir I have another question, the lower the MAD and MSE, the forecasting method used is more accurate?
That's correct.
@@joshemman Thank you again.
hi joshua
could you further evaluate for Normalised weighted Root Mean Squared logarithmatic Error,please
Big thanks you are GREAT , VOICE, VERBAL , SMOOTH EXPLANATION, THANK YOU :)
Thank you
How do you differentiate Mean absolute deviation vs Median absolute deviation which is also short for MAD
if i increase number of weeks then error will decrease or increase. if error is increase as shown in ur example that 2wma give better smoothing than 4 wma then it means as number of periods increases the smoothing error get increased.
Not at all. The errors depend largely on the data you have.
you are AMAZING
Thank you so much I understand everything keep up the good work 👍
Very incredible, wish you include more topic in that video lecture
if I got my next job, I must thank you
How about there is no given weight average but we need to calculate the three months and six montsh weighted moving averages?. Can someone help me/enlighten me please. THANK YOU
Please Josh how would interpret the 2.92 result?
Thank you sir!
Thank you very much
💛
Thank you !
Man, good job. It was helpful.
so finally there are 2 types of method if we got value 1 by calculating all given weight value so we have to have solve from 1st method if we are getting another value like 5 or 7 or 10 by calcuting so we have to do by the second method
i love this dude
If there three weights in question but two of them are given.
How can I calculate the third weight, since it wasn't given. Thanks
+MD Jahedul Islam
Just make sure the they add up to 1 (or 100%).
What is you were asked in a question like what would be the weighted moving average for week 6 if the weight were 0.40, 0.30, 0.20 and 0.10?
You assign the weights respectively to periods 5, 4, 3 and 2.
ohhh so then the weights would be 0.5, 0.4,0.3,0.2 and 0.1?
@@Eussub40
0.40, 0.30, 0.20 and 0.10.
Where did 0.5 come from?
@@joshemman I really don't know how to work out this equation. I'm doing an entrepreneurship course and I hate this part. The reason I said 0.50 cause you said assign the weight respectively to period 5 etc
@@joshemman maybe I misunderstood
How can we know what weights should be used?
Great explanation!! Thank you so much :)
what if the ( 4 weeks ) is not given, the question only says find the forecast for a specific month? how can i solve ?
how do you come up with weights of .4.3.2.1 for 4week Weighted average and for 2 week weighted average , how did u get Weights 3 and 2? is it an automatic assumption?
Yes. They are assumed (chosen randomly for the example)
well explained and very helpful, Thank you so much Joshua
In 2-week WMA case, weight 3 and 2, are they just random number? and how to get the optimal weights? thanks
+Andrew Lian
You can use Excel's Solver to obtain optimal weights. See th-cam.com/video/zOGfG65ASdA/w-d-xo.html
Joshua Emmanuel thank you! that would be helpful
Very good explanation, thanks
Hello! I got a question, I was reading about this method, and I saw that all the weights must be equal to 1, I'm a bit confused why did you choose weight 5 on the second example.
its just an example i think is it does not equal to 1
It's true that the total weight must be equal to 1, but he explains that even though his weight totals at 5, he divides his final answer by 5, so he gets the actual weight of one.
really helped well sir thank you t__________t
How do you know which weight values to use?
Mister i have a question F5 how to calculate i think writing error 2WMA
F5=45*3+40*2/5 but u write F5=45*3+44*2/5➡️43 Edit ur video please
Sorry about the typo. Unfortunately, the video cannot be edited. But I think you get the idea.
thank you for this amazing explanations 👌
how to decide of their weights ??
If the given weight equals to 1 means you don't have to dividw it by its n, then if the weight is not equal to 1 then you have to divide it by its n, right?
Yes. If the weights add up to 1, you're essentially dividing by 1 which appears like doing nothing.
@@joshemman Thank you.
Thank you, that was useful for my study!
That Really helped alot sir!
Thankew
kindly solve this Ques ..it's taken from one of the prestigious competitive exam of India..so the Ques Is- given the numbers 2,6,1,5,3,7,2. if the weights used are 1,4,1 .then weighted moving average of order 3 are given by?.
2,6,1,5,3,7,2 with weights 1, 4, 1. The sum of the wights is 6. For weighted moving average of order 3,
F4=(2+4*6+1)/6 = 4.5
F5=(6+4*1+5)/6 = 2.5
...
F8=(3+4*7+2)/6 = 5.5
Can u explain the same in ur video.?.I would be very grateful to u.. thank u for teaching it beautifully..
Why use weights 3 and 2 at 2WMA instead of using weights 2 and 1?
The weights are assigned based on the level of importance recent periods. They will vary from one problem to another.
Joshua you are the man
# In Python
#Weighted Moving Average 2WMA
sales = [39, 44, 40, 45, 38, 43, 39]
calc = lambda x: 0 if x == 0 else (sales[x] * 3 + sales[x-1] * 2)/5
forecast = [ calc(x) for x in range(0, len(sales) ) ]
print(forecast)
HOW DO I CALCULATE THE FORECAST GIVEN 3 WEIGHTS ONLY?
Thank you for thisssss 🥰🥰
thanks! i Got great ideas for this videos!
How can you calculate the sales for week 9 and 10.
will you always be given the weights?
Typically, yes.
can u explain decomposition on your nex video
hi sir, may i ask what weights to use in 3-WMA?
the weights are decided by the management who conducted the study based on what they see is important. they are not fixed numbers, you could choose any weights you want. but generally managemnet or the person who is doing the forecasting give the recent data more priority than old data which means higher weights for rececnt data