Math and Metal Detecting

[bob_e99]

I don't know if this has ever been discussed or if anyone has thought about this so apologies if it's a repeat or nobody cares. I was wondering if anyone has done a statistical analysis of the probability of finding a certain type of coin. If you think about year, population of that year, coin type (copper or silver), amount of coins minted and soil factors I think you can probably come up with a formula that would be interesting. I'm not sure if I'm missing anything. Probably can consider wealth factor, i.e. someone in the 1800's is carrying copper pennies and is probably more likely to keep a tight purse whereas people today lose change and don't think twice about it.

What made me think about this are the posting of people who keep logs and sum up all their finds so you can see the variety of coins found. For obvious reasons, silver coins are more prevalent due to its inert qualities and quantity minted but it would be interesting to break down to years or group of years.

Anyway, just a thought.

Thanks

Bob

 

[coinnut]

Also to consider is melted coinage, bank recalls after silver and gold were replaced with clad, coins sent overseas in trade (like the Trade Dollar) and many more. A formula for that may be bigger than the Drake Equation lol But someone who kept logs would be able to give a good ratio, but it would only be based on their hunting areas, skills, and machine capabilities, etc.... Not scientific, but a start. My results would be way off base from everyone elses, due to hunting colonial cellar holes. My large copper count exceeds my silver count. That would not be realistic for someone who does tot lots :yes: Just like a tot lot hunter's gold ratio would be way off base for me in the woods. I never heard of anyone doing a real study on it though. :thinkingabout: Interesting idea though.

 

[Epi-hunter]

Yep, that is a lot like I do for a living I am a doctor but also have a master's degree in Epidemiology (thus my forum name) which by definition means: The branch of medical science concerned with the occurrence, transmission, and control of epidemic diseases and drugs.

That theory translates. I have thought a lot about doing some kind of epi study about the topic you just mentioned, but there are a lot of different things that impact it (as George mentioned in his post). The most important being that finding a coin in any area depends mostly on individual skill levels, and I believe that is the most important factor. So I do not think any statistics generated from such would be at all meaningful, except as analyzed in the context of the person finding the coin. Too many human factors.

 

[CyberSage]

I have often thought about doing a study on my finds to date. It might prove useful. Great idea! I have a Quart Jar full of Wheats that I have found. It would be fun to look at dates and mint marks and enter them into a database for report generating. Sounds like a Winter project.

 

[Spiderwort]

Yep, that is a lot like I do for a living I am a doctor but also have a master's degree in Epidemiology (thus my forum name) which by definition means: The branch of medical science concerned with the occurrence, transmission, and control of epidemic diseases and drugs.

That theory translates. I have thought a lot about doing some kind of epi study about the topic you just mentioned, but there are a lot of different things that impact it (as George mentioned in his post). The most important being that finding a coin in any area depends mostly on individual skill levels, and I believe that is the most important factor. So I do not think any statistics generated from such would be at all meaningful, except as analyzed in the context of the person finding the coin. Too many human factors.

Epi. You wrote the word statistics. I'm getting so sleeeeeeepy. Please hurry and write something counter intuitive before I crash.

 

[randy]

I log all my finds in a spreadsheet and watch a couple of stats: silvers to total coin ratio, my target is 2%, current rate is 3.6%; and wheaties to silver ratio, my target is less than 3x, current ratio about 2.5x. (By comparison, for clad, pennies make up 39% of the total (but I don't dig zincolns), or, for pennies vs dimes and quarters, the ratio is 0.72. Why it is so much more favorable for clad than silver I dunno, but a wheaties to silver ratio approaching even 1x would be sweet, wouldn't it?. I imagine some of the disparity in ratio comes from not digging zincolns, and general inflation, therefore a goal of 3x seems reasonable).

I also specifically watch my nickel percentage as a percentage of clad. I read somewhere that nickels make up about 10% of pocket change; that is, the way the denominations work and add up, you should expect nickels to be about 10% of a large random pile of pocket change.

For me, I've seen that number drop to as low as 2-3% of my clads, and that tells me I'm too silver-obsessed and not digging enough low tones, and thus possibly missing out on the gold. I've made an effort to jack that up, and at least be above 5%, tho I still haven't found any gold in a while >{

It is true that skill and what you focus on matter. I've found 294 silvers and only 5 indians, and one of those indians was a fatty. I'm sure most folks have a less skewed silvers to indians ratio. If you count the two flying eagles I've found, that's 3 fatties to 4 bronze indians, which seems really whacked. Also, 3 half cents to 4 bronze indians seems really whacked as well.

 

[bob_e99]

Thank you all for some excellent points. Here is an interesting site, although I would verify the numbers with US mint documentation but it could be used as a start:

http://en.wikipedia.org/wiki/United_States_Mint_coin_production

Also, I would remove the detecting person from the equation and let's say it's a potential of what may be in the soil. Coinnut's points would also have to be researched as I believe the US mint keeps some records of how many coins are brought back to the mint for meltdown or whatnot.

Thanks again for your input. I'm going to try and dig up more data and while it may not be of any value when detecting, it may be interesting to see what is potentially out there.

Bob

 

[z118]

Yeah, it's fun to think about for sure. Here's my stats for every coin I've dug so far. My numbers are HEAVILY influenced by the fact that I like digging clad, my love of tot lots, and over a year's worth of hunting with the Tracker IV. My recent seasons show a higher percentage of old, very old, and silver coins, as well as better nickel numbers.

Randy, your silver percentage and ratio of silver to wheats makes me envious. But then again, I love clad and dig pennies so what do I expect?

The one hole in my spreadsheet is that I do NOT have a column for clad halves... I just enter them in as .5 in the dollar column. They don't turn up too often.

The old column includes wheats, and pre 1959 non war Jeffereson nickels. The very old column includes any non silver coin older than a wheat penny or Jefferson nickel. All silver gets lumped together regardless of age (or if it's foreign). Not the most rational categories but it has meaning for me and there's way too may lines on my spreadsheet to think about fixing it now!

 

[z118]

Along these lines I once posted (on another forum I think) asking in what order people had found their first old coins - meaning coins no longer in circulation. You'd think the order would tend to at least somewhat reflect the prevalence of coins, but this was not the case. Bob, your finds are a perfect example - you haven't dug a wheat or a Merc yet but you have found a Barber dime and a large cent. So much of it is just pure, blind happenstance and that's what makes it so much fun. You do everything you can to weight the odds of good finds with research, practice, and skill but at the end of the day it's about nothing other than what you happen to pass your coil over.

 

[RobW]

ok....apparently you all have WAY too much time on your hands...why don't you do something productive ....go detecting rofl

 

[bob_e99]

Along these lines I once posted (on another forum I think) asking in what order people had found their first old coins - meaning coins no longer in circulation. You'd think the order would tend to at least somewhat reflect the prevalence of coins, but this was not the case. Bob, your finds are a perfect example - you haven't dug a wheat or a Merc yet but you have found a Barber dime and a large cent. So much of it is just pure, blind happenstance and that's what makes it so much fun. You do everything you can to weight the odds of good finds with research, practice, and skill but at the end of the day it's about nothing other than what you happen to pass your coil over.

The person detecting skews the results because they pick the location. If I detect in the woods, chances are less likely that I will find clad but if I detect in a playground, chances are all I will find is clad and jewelry (depending on the age of the playground). That's why I was curious just to try and get a number of potentially lost coins. Not having detected for that long, I'm sure everyone looks for those old sites to get the best finds so this isn't a 'eureka' moment.


In any case, RobW is probably correct but my science background always makes me look at things in an analytical way. :interesting:
I was also just trying to calculate how many more lincoln pennies I need to find to deplete all the lost ones. I think the Sovereign is currently stuck on pennies.

 

[coinnut]

I think if you keep your own records, or if you tally the accounts of just the people that are detecting your areas of focus, you will be able to gather some good information. Let's take park and school hunting (excluding tot lots). If you regionalize it, so that you know the oldest coins the area has to offer, you can track your statistics to let you know the ratios of penny vs dime, Wheat vs, Memorials vs Indian, Silver vs clad, etc... This will be your base numbers. How is this helpful?? Well one way it's helpful is to see if it is time to move on to greener pastures. If you ratio count is going downhill, then your hunting grounds are being depleted and you need some new locations to get back to your base numbers. This keep you from just hunting the same ground over and over. Also if your numbers are not close to the numbers of others in the region, you need to read their posts and quiz them lol It may be a matter of machinery, experience or just something overlooked by you, but you need to find out why someone is doing better than you at the same types of locations. Statistics can help greatly if you are willing to compile them. I am too lazy and just prefer to hunt lol That is why I work harder to find what I find. If I was thinking smart, I would do much more research and double my finds :yes: It's all about how hard you are willing to work

 

[bob_e99]

I think if you keep your own records, or if you tally the accounts of just the people that are detecting your areas of focus, you will be able to gather some good information. Let's take park and school hunting (excluding tot lots). If you regionalize it, so that you know the oldest coins the area has to offer, you can track your statistics to let you know the ratios of penny vs dime, Wheat vs, Memorials vs Indian, Silver vs clad, etc... This will be your base numbers. How is this helpful?? Well one way it's helpful is to see if it is time to move on to greener pastures. If you ratio count is going downhill, then your hunting grounds are being depleted and you need some new locations to get back to your base numbers. This keep you from just hunting the same ground over and over. Also if your numbers are not close to the numbers of others in the region, you need to read their posts and quiz them lol It may be a matter of machinery, experience or just something overlooked by you, but you need to find out why someone is doing better than you at the same types of locations. Statistics can help greatly if you are willing to compile them. I am too lazy and just prefer to hunt lol That is why I work harder to find what I find. If I was thinking smart, I would do much more research and double my finds :yes: It's all about how hard you are willing to work

You make a lot of good points. Up until now I've been detecting pretty much in the same area close to home. Now that I'm getting more comfortable with it, I'm starting to use the various tips given by members of this forum, my son and some friends to locate potential sites. However, what I'm finding is that pretty much all of the 'logical' sites have been detected to barenness so if I really want to makes some finds worth posting, I'm going to have to really think outside the box that other people are thinking outside of.

Thanks for your input and continued luck in your hunting.

 

[SeabeeRon]

Interesting thread Bob, thanks for posting it! :yes:

 

[russellt]

you guys are killing me. i stink at math . to the extent that i failed trig 3 times before i quit college. but being a phone guy isnt so bad . i do ZERO math :twirlingeyes:

 

[bob_e99]

I still think about this when I have a few moments and try to look up statistical numbers once in a while. I recently came across this which makes it look like people in Virginia should be cleaning up in old coins especially considering how well Angel does in Connecticut. I was also surprised to see the numbers for Massachusetts. I need to head south a bit.