“Teach me,” she said.

[Cecily]

Hello and welcome to my thread where you lovely people get volunteered to fill in the gaps of my education. How this works is I ask a question, probably math / statistic oriented and what you do is helpfully explain it to me, ideally, or try really hard to troll me. Haha you... you devils you.

Anyone else feel free to contribute academic-related questions. Please avoid topics on gender studies, feminism, or politics as they already have their own threads.

[America]

pose me a question i'm spinning up an "accomplished academic" trolling angle

[Cecily]

So to start this off, I’ve taken a statistics class years ago at a 4y college and all I learned was how to input numbers into a program. I’d really like to relearn the useful information to help me understand research journals, but for now I have a question about calculating percentile rank.

I have data for 5th%, 95th%, mean, and total number.

Can I use this information to plug in a number to determine its percentile rank?

Ex:
My weight = 196 lbs
Mean = 153.2 lbs
5th percentile = 105.5 lbs
95th percentile = 225.6 lbs
N = 8764

How do I figure out my rank?

Using data from this table:
http://andreaportman.tripod.com/averages.html

[loramin]

Originally Posted by Cecily [You must be logged in to view images. Log in or Register.]

So to start this off, I’ve taken a statistics class years ago at a 4y college and all I learned was how to input numbers into a program. I’d really like to relearn the useful information to help me understand research journals, but for now I have a question about calculating percentile rank.

I have data for 5th%, 95th%, mean, and total number.

Can I use this information to plug in a number to determine its percentile rank?

Ex:
My weight = 196 lbs
Mean = 153.2 lbs
5th percentile = 105.5 lbs
95th percentile = 225.6 lbs
N = 8764

How do I figure out my rank?

Using data from this table:
http://andreaportman.tripod.com/averages.html

I think you can't, because you don't have enough info. But stats isn't my forte so hopefully someone else has a better answer.

The way I see it ... the mean is 153.2 lbs right? That could be because there was one insanely fat fuck on the heavy end, or it could be a lot of "on the heavier side but not that heavy" people on that end. Same deal on the other end, you could have like three bulimic people who weigh as much as a concentration camp survivor, or you could just have a lot fairly fit people. Either case could give you that same mean of 153.2 but your placement will be different depending.

The only way to truly know where you place in a dataset is to have that whole dataset. That being said, with the percentiles I would imagine you could guess pretty close to the correct answer by using math ... but again stats aren't my strong suit so someone else would have to provide that math.

[Lune]

Originally Posted by loramin [You must be logged in to view images. Log in or Register.]

I think you can't, because you don't have enough info. But stats isn't my forte so hopefully someone else has a better answer.

The way I see it ... the mean is 153.2 lbs right? That could be because there was one insanely fat fuck on the heavy end, or it could be a lot of "on the heavier side but not that heavy" people on that end. Same deal on the other end, you could have like three bulimic people who weigh as much as a concentration camp survivor, or you could just have a lot fairly fit people. Either case could give you that same mean of 153.2 but your placement will be different depending.

The only way to truly know where you place in a dataset is to have that whole dataset. That being said, with the percentiles I would imagine you could guess pretty close to the correct answer by using math ... but again stats aren't my strong suit so someone else would have to provide that math.

This is correct, the distribution could be bimodal, steep, shallow, you don't know, and your rank/percentile depends on that. Think you need access to the data set, and with N=thousands, a computer/spreadsheet to calculate this, because it involves ranking the data.

Even if you had just the standard deviation you could assume a normal curve and estimate your percentile based on how many standard deviations you are from the mean, but you don't have that.

[Cecily]

Originally Posted by Lune [You must be logged in to view images. Log in or Register.]

This is correct, the distribution could be bimodal, steep, shallow, you don't know, and your rank/percentile depends on that. Think you need access to the data set, and with N=thousands, a computer/spreadsheet to calculate this, because it involves ranking the data.

Even if you had just the standard deviation you could assume a normal curve and estimate your percentile based on how many standard deviations you are from the mean, but you don't have that.

Ty Lune!

She did cite the research she took the data from so I might be to dig a little deeper and get that information. Seems like a fun project to get the hang of stats again.

[hobart]

Originally Posted by Lune [You must be logged in to view images. Log in or Register.]

This is correct, the distribution could be bimodal, steep, shallow, you don't know, and your rank/percentile depends on that. Think you need access to the data set, and with N=thousands, a computer/spreadsheet to calculate this, because it involves ranking the data.

Even if you had just the standard deviation you could assume a normal curve and estimate your percentile based on how many standard deviations you are from the mean, but you don't have that.

Agree.

Don't need the entire set, but you do need more than you have which is really just you. Look up Cochran's formula and you can calculate what sample size you'd need at any given confidence level. Then you might be able to look to a study for your data.

Ideally I think you'd want to use a study of Americans where weight was taken but not one related to weight loss/gain. Now is there a study like that where you can get the data set? No idea.

[Cecily]

Naw. I’m not in a new age demographic bracket till April. Nice thing is I blend in with college kids still. It scares me how roughly 30+ hits a lot of people. My mom looks really good for being close to 60, so I think I’m going to be very fortunate in that regard.

Originally Posted by loramin [You must be logged in to view images. Log in or Register.]

I think you can't, because you don't have enough info. But stats isn't my forte so hopefully someone else has a better answer.

The way I see it ... the mean is 153.2 lbs right? That could be because there was one insanely fat fuck on the heavy end, or it could be a lot of "on the heavier side but not that heavy" people on that end. Same deal on the other end, you could have like three bulimic people who weigh as much as a concentration camp survivor, or you could just have a lot fairly fit people. Either case could give you that same mean of 153.2 but your placement will be different depending.

The only way to truly know where you place in a dataset is to have that whole dataset. That being said, with the percentiles I would imagine you could guess pretty close to the correct answer by using math ... but again stats aren't my strong suit so someone else would have to provide that math.

Thank you, Loramin! I was wondering if lacking the whole range would be a problem. I’m considering outliers when I check my results vs the ones on the table. Like 95 for waist is around 46” and I looked at that in the mirror with measuring tape and was sad people have to deal with that

[Vormotus]

Originally Posted by Cecily [You must be logged in to view images. Log in or Register.]

So to start this off, I’ve taken a statistics class years ago at a 4y college and all I learned was how to input numbers into a program. I’d really like to relearn the useful information to help me understand research journals, but for now I have a question about calculating percentile rank.

I have data for 5th%, 95th%, mean, and total number.

Can I use this information to plug in a number to determine its percentile rank?

Ex:
My weight = 196 lbs
Mean = 153.2 lbs
5th percentile = 105.5 lbs
95th percentile = 225.6 lbs
N = 8764

How do I figure out my rank?

Using data from this table:
http://andreaportman.tripod.com/averages.html

You know, sober I might have given you a solid answretr, see I am a colege degree Psychologist, I had during my 5 years course , over 8 tipes of statistcs , like introduction to statistics, advanced statistics I 2 and 3 and then we have Psychodinamic Statistis 1 and 2 and another i dont remember. I saw som any statistic i remember even being able to decompile MMPI and Bender tests into validates items to create new tests with a hifg degree of validation ... that stuff has server me 0% in real life.

LIKE 0% except showing off in a crap reddit thread once or twice in over a decade.

My only real input to you is to study , pass and graduate and then forget abvout everything and learn to either code, a second and third language and perhaps learn how to save money, manage a budget and then invest in either real state in emerging thrid world countries or invest in solid stock like mutuals that give above average depreciation rates of the usd so you can at least keep the same money every year over the basic inflation ratesof it.

That is the only trhing that will help you in life.

Ahh and get a sensible partner that does not waste your own resources, that is a super plus alongisde not having more than one chil dif you have as alife gfoal to reproduce your genetic line.

yep, that is the only trhing you will need to suceed at life. Please remember no corporation whatsoeves, alongside f"riends2" you might make there are really honest or real , the only people you can trust you can count on your hand and have fingers left to count.

Also never ever tell anyone what you really own, or how much money you make. fact is, I have foudn if you portray yourself as poor you will usually get more out of people, as they will either ignore you or dismiss you as non threatening

what else? yep, never buy a car because its fancy or represent you, cars are the worst investment of your money due to their depreciation rate never buy fancy clothes of items to show you are well, that is literally wasting money only to show people, that do not really care about you you are better than them, that is a total watse of your money and time.

hmmmm yeah, my granny alwaysd told me you had to be aware of your surroundings, have spatial awareness of where you are all the time. this might save your life.

if possible and in theus, learn to do CPR, and how to fire common guns, or how to disarm or descalate situations yes.


be aware protecting your honor is bullshit if it might entail losing your life, everyone else is apotential enemy during thesesituations and though yo might have enough courage, if they outnumber yu it is a losing game.

Learn how to avoid conflict with strangers, do not drink un unsafe space and enjoy small things, like friendship and family.

yep, this is the same adive I would give t my dead son. yep.

hope it helps you man or woman.

be safe always and never worry too much about people, they will never be there when needed, and those that are, cherish themlike gold!

Much love to you my friend!

[America]

that website is ADORABLE