IIF Open Source Forecasting software workshop and smooth

Sticker of the smooth package for R

Here is one thing you have probably not heard of: a workshop on Open Source Forecasting software, held in Beijing on 26th – 27th June 2025. This was a closed event, with speakers attending by invitation only. It focused on recent advancements and potential avenues in open-source forecasting software. But why am I writing about … Read more

NATCOR course on Forecasting and Predictive Analytics, September 2025

Are there any PhD students in the crowd who want to learn more about forecasting? What about academic supervisors who have such students? Show me your hands! This post is for you! This September, we (Lancaster Centre for Marketing Analytics and Forecasting members) will deliver the Natcor course on Forecasting and Predictive Analytics at Lancaster … Read more

SBC is not for you!

Stop using SBC!

I’ve been acting as a reviewer lately, providing comments on papers about intermittent demand, and I’ve felt a bit frustrated by what some authors write. Let me explain. Several papers I reviewed claim that demand can be either intermittent or lumpy. They then mention the Syntetos-Boylan-Croston (SBC) classification and use the thresholds from Syntetos et … Read more

Fundamental Flaw of the Box-Jenkins Methodology

Sarah by Yegor Kamelev

If you have taken a course on forecasting or time series analysis, you’ve probably heard of ARIMA and the Box–Jenkins methodology. In my opinion, this methodology has a fundamental flaw and should not be used in practice. Here’s why. When Box and Jenkins wrote their book back in the 1960s, it was a very different … Read more

On randomness and uncertainty

A weather forecaster rolling a dice

Everything is random! Your data, your model, its parameter estimates, the forecasts it produces, and even the minimum of the loss function you used. There is no such thing as a “deterministic” forecast – everything is stochastic! Whenever you work with data, you are working with a sample from a population. In some cases, this … Read more

Svetunkov & Sroginis (2025) – Model Based Demand Classification

Stockouts detection algorithm, Figure 2 from the paper https://doi.org/10.48550/arXiv.2504.05894

For the last year, Anna Sroginis and I have been working on a paper, trying to modernise demand classification schemes and make them useful in the brave new era of machine learning. We have finally wrapped it up and submitted it to a peer-reviewed journal. But the temptation to share was too strong, so we … Read more

Challenges related to seasonal data: shifting seasonality

Hourly seasonal plot from the paper https://doi.org/10.1080/20476965.2023.2200526

There are many different issues with capturing seasonality in time series. In this short post, I’d like to discuss one of the most annoying ones. I’m talking about the seasonal pattern that shifts over time. What I mean is that, for example, instead of having the standard number of observations in the cycle (e.g., 24 … Read more

Naming conventions for seasonality types

In forecasting, the term seasonality doesn’t always mean what you think it does. It encompasses more than just patterns repeating from one season to the next. In fact, seasonality covers a wide range of periodic behaviors, and can have some issues associated with the naming conventions. Should we discuss? First things first: when we say … Read more

There is no such thing as “the best approach for everything”

If someone tells you that method X solves all problems and is the best one ever, they are either lying intentionally or do not fully understand what they are talking about. There is no such thing as “the best approach for everything”. Let me explain. Consider two products sold by retailers: ice cream and bread. … Read more