« first day (1244 days earlier)      last day (231 days later) » 

Mike Pierce
Mike Pierce
00:30
In R (and elsewhere?) there are the p___ and d___ prefixes to distribution functions. Like pbinom and dbinom. What do the p and d stand for?
(Like I know what the functions are) And d is probaly for "density". What does 'p' stand for though?
Xander Henderson
Xander Henderson
00:51
@MikePierce stat.ethz.ch/R-manual/R-devel/library/stats/html/Binomial.html
dbinom gives the density, pbinom gives the distribution function, qbinom gives the quantile function and rbinom generates random deviates.
The "d", "q", and "r" all seem pretty self-explanatory.
Based on this answer, I would surmise that p is for "probability".
That answer indicates that, for example, pnorm(1) is $P(X < 1)$, where $X$ is a standard normal random variable.
Mike Pierce
Mike Pierce
Does 'p' for 'probability' sense? Or is this some historical naming relic?
*make sense
Xander Henderson
Xander Henderson
No idea. I don't work with R very often.
I makes a certain facile sense. :\
Mike Pierce
Mike Pierce
I don't either. That's why I'm trying to make sense of the names now so I don't have to look them up next time I use R ... everytime I use R
Xander Henderson
Xander Henderson
Yeah, but... that's what R wants you to do. You have to look them up every single time. Because R hates you.
Mike Pierce
Mike Pierce
01:06
Okay. Yes. That is pedagogically meaningful. "kids, why are these functions named this? Answer: because R hates you"
Xander Henderson
Xander Henderson
Yes. Very.
I would go with "probability"
Looking at the documentation, it looks like p[distribution] gives the value of the CDF. It is the probability that the random variable is less than the input.
as a mnemonic, I think that is the best you can do.
Also, why the heck are you using R?
Aren't you, like, a dirty algebraic topologist?
Mike Pierce
Mike Pierce
Thx I hate it. Because then dbinom corresponds to the Probability Distribution Function and pbinom refers to the Cumulative Distribution Function :c
They're ALL probabilities
Xander Henderson
Xander Henderson
I mean... R is a prob and stats package.
Everything is a probability to R!
Mike Pierce
Mike Pierce
I mean, I'm sitting in Zoom class now and my students didn't show up, so now I'm just figuring out how to make the R prompt colorful ;)
Xander Henderson
Xander Henderson
Heh.
Mike Pierce
Mike Pierce
01:10
But yeah, dirty algebraist teaching elementary stats
Xander Henderson
Xander Henderson
I just finished office hours. No one showed up.
But I created a Discord server for them, and I do have a few students showing up there.
Mike Pierce
Mike Pierce
FYI, don't consider the OpenStax Elementary Stats book
The kiddos sure do love discord
Xander Henderson
Xander Henderson
Indeed.
Anywho, COVID shot number two is kicking my tail. Now that my office hours are over, I need to go to bed.
Laters.
Mike Pierce
Mike Pierce
Goodnight boss!
Xander Henderson
Xander Henderson
Say "Hi" to Surge for me, if you ever get back there.

« first day (1244 days earlier)      last day (231 days later) »