Analysis of variance (ANOVA) is a collection of statistical models and their associated estimation procedures (such as the “variation” among and between groups) used to analyze the differences among means. ANOVA was developed by the statisticianRonald Fisher. ANOVA is based on the law of total variance, where the observed variance in a particular variable is partitioned into components attributable to different sources of variation. In its simplest form, ANOVA provides a statistical test of whether two or more population means are equal, and therefore generalizes the t-test beyond two means. In other words, the ANOVA is used to test the difference between two or more means.
Consider this: Analysis of variance (ANOVA) is a statistical method used to compare the means of three or more groups and determine whether there are statistically significant differences between them. It assesses whether the variability among group means exceeds what would be expected due to random variation alone.
“I was a fool and what i’ve seen has made me two fools.”
Rafael Alberti, Spanish poet
Friends, Europeans, and fellow citizens, it’s time that we all spoke out against wrongdoing, criminality, and impunity. It’s time we took a stand against injustice wherever we find it. And it’s time to say that enough is enough.
Dud: Pete, did data exist before data warehousing?
Pete: Yes, and tea and hot water. And the only social media platform available to dizzy gobshites was the local boozer.
What on earth have you been listening to, Dud.
Dud: There was this prize eejit on an industry blog saying that data used to mean data warehouses but that it doesn’t anymore.
Pete: Oh, no. Insufferable countenance, Dud.
Dud: I can’t be having it.
Pete: Don’t give in, Dud. Stay and fight the good fight.
Dud: Fancy a beer?
Pete: Okay.
Dud: Here you go. Cheers!
Pete: So, cheers to that too. And now, where to begin? Ah, now I’ve got it.
The problem is, Dud, that many of these ill-informed blog jockeys think that data warehousing is like a car and that to improve it, you have to build a bigger and better car, or in other words, a bigger and better data warehouse.
Dud: Makes a lot of sense, Pete. But could we elaborate on that?
Pete: Look at it this way, Dud, we might buy a car because we want to impress our neighbours and friends, but the whole idea of getting a car is usually to have something that will help us to get from A to B and back again, safely, cost-effectively and without driving us insane.
The car is a significant part of the means, but there is much more to it.
Dud: I see.
Pete: The car is just part of the analogy, Dud. There is a whole raft of things that can be included in our journey from A to B, including the automotive technology used in the car; the streets, roads and highways; the bridges; the tunnels; the parking places; the fuel or energy; the driving skills; the rules, regulations and best principles; the Police; the guarantees; the training, coaching and continuous learning; the certification; the navigation system; the in-vehicle entertainment; the trailer, caravan or bike rack; the triangles, the yellow jacket and the warning lights you can place on the vehicle if it has broken down; the breakdown and recovery services; public healthy facilities; the hospitality outlets; the pedestrians; the other vehicle drivers; the other cars; livestock on the road; wild animals; the weather; rain, snow, ice and high winds; the gas stations or electric supply points; anti-freeze, oil and windscreen cleaner; and, the passive and active security. And that’s just off the top of my head.
Dud: So, it’s pretty comprehensive, Pete.
Pete: As it should be, Dud. Data Warehousing is about getting from A to B; it’s not just the car but everything that goes with it. Pretending otherwise is just perpetuating a stupid, vacuous and ignorant lie.
Dud: It also doesn’t consider our many options, depending on the circumstances. In the case of transport? Buses, trains, planes, boats, lifts, escalators, bicycles, electric and manual roller-blades, skateboards, motorbikes, horses, and just walking.
Pete: Well said, that man!
Martyn Jones, Santiago de Compostela, 17th October 2024.