by Jenab6 » Thu 23 Oct 2008, 11:21:22
There's a lot of technical economics talk in this thread that looks as if it is trying to head the reader's thinking away from the nuts and bolts of the topic.
Yesterday I opened a can of tuna fish, and today I opened another. I weighed each can intact: 202.0 and 203.5 grams. I removed the tops with a can opener, and the removed lids each weighed 8.0 grams. The empty cans, after being emptied, washed and dried, weigh 25.5 grams each. Which means the metal and paper packaging on the item weighs 33.5 grams, which means that the contents of the cans weighed 168.5 grams and 170 grams, respectively.
The "net weight" advertised on the outside of the can is 170 grams.
However, that is misleading. A lot of that weight is nothing but added packing water. After pressing out enough water that the tuna fish in the can is merely moist, rather than soup, the cans plus the tuna weighed 142.5 and 146.0 grams, respectively. Since the can without the lid weighs 25.5 grams, the weight of the moist tuna at that point was 117 grams and 120.5 grams.
What the customer intends to get in exchange for his money is that "moist" tuna, which is neither dry as dust nor as wet as soup. What he uses from the can is that ~120 grams of moist tuna whose weight I have found. The seller thus cheats the buyer by selling him only 12/17 of the advertised quantity of product, and he disguises his cheating by the inclusion of excessive packing water.
The inclusion of 50 grams of excessive packing water is equivalent to a concealed price increase (per gram of moist tuna) of 41 percent.
$this->bbcode_second_pass_quote('WildRose', 'J')ust the other day when I was shopping for groceries, an elderly woman and her husband pointed out to me that a product they regularly buy had a smaller amount in the same container for the same price, but I don't remember what product it was.
Could be coffee. Those cylinder cans were originally designed to hold a pound of coffee, which, 40 years ago, was ground to a fine powder. The powder packed well, so that 16 ounces of coffee fit snugly inside the can. Sometime after that - I don't know exactly when - the coffee sellers began coarsening the grind, and the coarser grind packed at a lower density because of the air gaps between the larger coffee grains. The coffee sellers coarsened the grind gradually, until, instead of 50-100 micron coffee powder, they were selling millimeter sized coffee gravel. Subsequently, they began incompletely filling the coffee cans. While this was going on, they conscientiously relabeled the net weight information printed on the side of the coffee can. Over time, the numbers went from 16 to 15 to 14 to 13 to 12, and now they say 11.5 ounces.
I'm something of an oddball in that I check those numbers. When I don't believe those numbers, I get out my triple beam balance and test the contents manually. But most people just assume that the seller isn't out to get them, that the seller is an honest guy, that the seller isn't going to play funny tricks like putting less product in the same size can and then use window dressing techniques to hide the reduction. Most people are fools, I guess.
$this->bbcode_second_pass_quote('WildRose', 'S')omething else I've noticed is that you have to check the large or "economy" sizes of products you buy to be sure you're getting the best value for your money. For example, if you're looking at bar soap in packages of 12 or 24, often the larger package is not the best deal; you'd be better off buying two of the smaller ones. You just have to calculate what you're paying per bar. Same goes for toilet paper, etc.
Ah, that's another thing. Most people should, but don't carry a calculator into the store with them and spend as much time punching its buttons as walking from aisle to aisle. I don't usually need the calculator because I've practiced doing arithmetic mentally for a long time. Sometimes buying in volume results in a discount. Sometimes, it does not. Occasionally, it's the reverse.