Een enkele reis van 100 tariefeenheden kost in 2026 € 22,70. Hoe NS op dat bedrag komt, staat nergens. De officiële prijslijst geeft op pagina 6 tot en met 10 alleen een lange tabel, met per tariefeenheid een prijs. Ik heb geprobeerd de formule erachter terug te rekenen. De korte versie: een opstaptarief plus een…
I work seasonal jobs in Europe and spend the winters in Southeast Asia, so my money lives in a Dutch current account, a savings account, a credit card, a multi-currency app, an online wallet, a money-transfer service and, most of the time, a wallet full of local cash. No budgeting app handles that well. Banks…
Waarom fondsen campings kopen die als camping bijna niets verdienen Hetzelfde stuk grond met dezelfde huisjes is voor de ene koper negen miljoen waard en voor de andere veertig. Dat verschil verklaart wat er met Nederlandse campings gebeurt. Jaarplaatsen verdwijnen, er komen chalets voor terug, en de nieuwe eigenaar heet Blackstone, PAI of het staatsfonds…
Het KNMI berekent het landelijke neerslagtekort uit dertien stations. Op X kreeg ik te horen dat dat er veel te weinig zijn. Dus heb ik het uitgerekend. De discussie begon met een neerslagtekortgrafiek en liep zoals dat gaat op X. Mijn gesprekspartner, @dimgrr, hield vol dat je op dertien puntmetingen geen landelijke droogte kunt baseren:…
Improving Cleaning Quality Through Statistical Sampling and Performance Incentives It is hard to get a consistently high cleaning standard from an external company. The usual problem isn’t the people or the mops — it’s the incentive structure. Do well for months running, and nothing in particular happens: no recognition, no reward. Do badly, and often…
Hoewel de thermometer in alle gevallen 29 graden aangeeft, voelt de hitte tijdens het hardlopen in Da Nang anders dan gedurende acroyoga in Chiang Mai — en weer anders dan als je een biertje op een Amsterdams terras drinkt.
Vervolg op Sterfte vs temperatuur (november 2023) naar aanleiding van enkele vragen op X.com Samenvatting In het eerdere artikel werd op basis van KNMI- en Eurostat-data een V-vormige relatie tussen gemiddelde weektemperatuur en sterfte in Nederland gevonden, met een optimum rond 16,5 °C. De geschatte effectgrootte — ongeveer 1% minder sterfte per °C onder het…
Data Analysis · Climatology · Trend Methods · April 2025 The KNMI uses a LOESS span denominator of 42 to approximate a 30-year running average. But what if you want a different smoothing window? This article derives both the theoretical relationship and an empirical formula — and finds that the two are surprisingly different. Read…
👉 This is a dummy showcase based on a real project. The yoga chain setting is fictional. You can view the live version here (‘wake up’ if needed). Please note that the multiple regression results differ from those in the article because the data in the script are generated randomly. Summary In 2025, student surveys…
Magic black box of zuivere wiskunde? Elk jaar in juli publiceert het RIVM de verwachte sterfte. Dit jaar valt die lager uit dan verwacht, terwijl de werkelijke sterfte juist stijgt. Dat roept vragen op: hoe werkt dit algoritme eigenlijk? Wordt het aangepast wegens een bepaald agenda? Ik heb al eerder over deze verwachtingen geschreven en…
I work at a campsite and I often enjoy the sunset. But it moves through time. so I was wondering, “Where exactly does the sun go down?”. If you follow my blog, you know that I didn’t just want to know. I wanted to see it, understand it, and visualize it. So I pulled out…
It sounds like something pulled from science fiction or a poetic metaphor: every time you breathe, you might be inhaling a molecule from Julius Caesar’s final exhale. But this idea is more than just a thought experiment — it’s grounded in probability, physics, and some surprisingly simple math. Let’s walk through how this works, why…
In the ever-evolving world of algorithmic trading, finding robust strategies that can weather different market conditions remains the holy grail for investors. Today, I want to share insights from my analysis of several VIX-based trading strategies that have gained attention in financial circles. What We’re Examining The strategies I’ve been testing use the CBOE Volatility…
On Instagram I saw a reel where Steve Ballmer, ex-CEO of Microsoft explained a game to an interviewer. I decided to see if it is a wining game or not. You can find the python code here How the Game Works Here’s what happens in the game: The money part is simple: guess right on…
Summary This study examines the relationship between mortality rates, wastewater virus measurements, and COVID-19 vaccination levels during the pandemic. Using open data from CBS, Eurostat, and vaccination records, the analysis applies multiple linear regression, VIF tests, and interactive visualizations in Python. The results show a strong positive correlation between virus concentrations in wastewater and mortality,…
Viager Real Estate: Betting on Life and Death Imagine a real estate deal where your fortune depends on how long someone lives. It’s called “viager,” a centuries-old French practice where buyers and sellers gamble on life expectancy. Now, with the help of AI and advanced modeling, this risky bet is getting a modern twist. The…
In the world of house cleaning, efficiency and thoroughness are key. But what happens when we apply data science and probability theory to this everyday task? This summer I was preparing mobile homes on a camping. During this work, different thoughts and questions came up. How many days would I need to see at least…
Abstract This study presents a novel approach to analyzing excess mortality during the COVID-19 pandemic using quadratic curve fitting. By comparing linear and quadratic models applied to pre-pandemic mortality data, we demonstrate that quadratic fitting results in lower estimates of excess mortality for the years 2020 and beyond. This finding suggests that previous linear extrapolations…
There was an article in the Netherlands with people working only a part of the year and it was called part-time retirement. The thing with the article is that they only showed people with good income jobs and that helps definitely to do so. Well, you can do it with a salary slightly above minimum…
In-Depth Analysis of Cleaning Times Using the Weibull Distribution Understanding and predicting cleaning times is essential for efficient resource management and operational planning. This article is about the application of the Weibull distribution for analyzing cleaning times, particularly focusing on predicting the maximum time needed to clean multiple accommodations with a high level of confidence….
Dit artikel behandelt het creëren van een trendlijn met behulp van de LOESS-methode, zoals toegepast door het KNMI. Besproken wordt hoe LOESS in Python kan worden toegepast. Lees ook het vervolg artikel From SMA to LOESS waarin ook de wiskunde achter deze methode wordt beschreven en uitgelegd LOESS, wat staat voor “Locally Estimated Scatterplot Smoothing,”…
Inleiding De oversterfte tijdens de COVID-19-pandemie in Nederland is een belangrijk onderwerp van onderzoek geweest. Twee prominente instellingen, het Rijksinstituut voor Volksgezondheid en Milieu (RIVM) en het Centraal Bureau voor de Statistiek (CBS), hebben elk hun methoden ontwikkeld om de oversterfte te schatten en te analyseren. Vanaf afgelopen december heeft het RIVM het overgenomen van…
Replication of Cumulative Rainfall Deficit Chart in the Netherlands On Twitter, a chart of the cumulative rainfall deficit was posted, presenting a challenge to replicate it. Rainfall deficit is an important metric in hydrology and agriculture, representing the difference between the amount of precipitation and evaporation. When evaporation exceeds precipitation, a rainfall deficit occurs, leading…
Understanding Temporal Variability in Bus Arrival Times and Its Implications on Travel Planning Introduction Efficient public transportation is vital for urban areas, offering convenience and reducing environmental impact. However, unpredictable bus schedules pose challenges for commuters, making it difficult to arrive on time for appointments or connections. This study focuses on two bus lines that…
In this analysis, we’re juxtaposing the Return on Investment (ROI) presented by brokers against the actual ROI. Brokers gauge the annual rent percentage (after deducting expenses) relative to the initial investment, giving ROI’s up to 20%. This evaluation spans the entire investment period, factoring in yearly rent increments. We’re exploring scenarios for both freehold and…
In een artikel van Marc Jacobs over oversterfte wordt een aanname van het CBS. De aanname is dat elke graad Celsius dat deze temperatuur hoger is dan de gemiddelde temperatuur in de week 3 tot en met 10 leidt tot 1 procent minder sterfte. Wanneer de temperatuur boven de 16,5 graad stijgt, neemt de sterfte…
The article Total Meat Intake is Associated with Life Expectancy: A Cross-Sectional Data Analysis of 175 Contemporary Populations by You [*] examined the association between meat intake and life expectancy at a population level based on ecological data published by the United Nations agencies. Their results were Worldwide, bivariate correlation analyses revealed that meat intake…
The study of Chuck Connell has been replicated for the Netherlands. His main findings were Method I used Python to analyse the data. I used the code of Chuck as base, I optimized it and made it more pythonic (with the help of ChatGPT)and added some things.The interface and output is done with Streamlit and…
Last month, my roommate introduced me to the concept of Dollar Cost Averaging (DCA) in the context of Bitcoin with great enthusiasm. According to this strategy, consistently purchasing a fixed amount of Bitcoin every month would yield greater profitability compared to making a single lump-sum investment. Intrigued by this notion, I embarked on a quest…
I was inspired by a tweet from Karin van der Wiel where she plotted the yield of her solar system to a theoretical value.(*) I wanted to see if I could replicate it with the yield of solarpanels of a friend. I took the daily weather data of the KNMI from their site(*) and used…
On Twitter the following image is shared widely what should prove that the 4th vaccin is causing excess deaths. Let’s see if this is likely to be true Method Death numbers: Vaccination numbers This is done in Excel Results A graphic design program is used to compare the graphs of Schetters and the found values…
Abstract Every 30 to 50 days, the Vaccin Effectiveness decreases with 10%-points. Introduction In several studies around the world, waning is seen for Vaccin Effectiveness (VE) for infection, hospital admission or death. The waning effect for infection is investigated. NotesMultiple research shows that the VE for severe disease, hospitalization and death remains high!This analysis has…