Displaying 20 results from an estimated 2000 matches similar to: "Bar charts, frequencies known, intervals of varying width"
2004 Jul 05
2
Failing on reading a "slightly big" dataset
I have a file with 4 columns per line, all pipe delimited.
$ wc -l cmie_firm_data.text
89325 cmie_firm_data.text
$ ls -al cmie_firm_data.text
-rw-r--r-- 1 ajayshah ajayshah 4415637 Jul 5 15:25 cmie_firm_data.text
$ awk -F\| '(NF != 4)' cmie_firm_data.text
$ head cmie_firm_data.text
All figures are for the year 20030331|||
Company|GVA Less Interest (Rs. thousand)|Interest (Rs.
2012 Jul 13
2
Power analysis for Cox regression with a time-varying covariate
Hello All,
Does anyone know where I can find information about how to do a power analysis for Cox regression with a time-varying covariate using R or some other readily available software? I've done some searching online but haven't found anything.
Thanks,
Paul
2017 Jul 10
0
fit lognorm to cdf data
* fitdistr?
* it seems unusual (to me) to fit directly to the data with lognormal... fitting a normal to the log of the data seems more in keeping with the assumptions associated with that distribution.
--
Sent from my phone. Please excuse my brevity.
On July 10, 2017 7:27:47 AM PDT, PIKAL Petr <petr.pikal at precheza.cz> wrote:
>Dear all
>
>I am struggling to fit data which form
2017 Dec 19
2
MemorySSA question
On Tue, Dec 19, 2017 at 9:10 AM, Siddharth Bhat via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> I could be entirely wrong, but from my understanding of memorySSA, each
> def defines an "abstract heap state" which has the coarsest possible
> definition - any write will be modelled as a "new heap state".
>
This is true for def-def relationships, but
2003 Jul 25
5
named list 'start' in fitdistr
Hi R lovers!
I'd like to know how to use the parameter 'start' in the function
fitdistr()
obviously I have to provide the initial value of the parameter to optimize
except in the case of a certain set of given distribution
Indeed according to the help file for fitdistr
" For the following named distributions, reasonable starting values
will be computed if `start'
2007 Jul 16
4
[LLVMdev] [PATCH] Re: Pluggable Register Coalescers
Hi David,
Sorry I should have replied earlier. I really don't like this dual
interface approach. To me, this muddles things without offering any
real useful new functionalities.
IMHO, if a register coalescer is tied to a particular allocator. Then
either it should simply belong to that allocator or that we have to
allow the allocator to act as a pass manager itself, i.e. it can
2011 Aug 26
2
How to generate a random variate that is correlated with a given right-censored random variate?
Hi,
I have a right-censored (positive) random variable (e.g. failure times subject to right censoring) that is observed for N subjects: Y_i, I = 1, 2, ..., N. Note that Y_i = min(T_i, C_i), where T_i is the true failure time and C_i is the censored time. Let us assume that C_i is independent of T_i. Now, I would like to generate another random variable U_i, I = 1, 2, ..., N, which is
2007 Sep 07
1
How to obtain parameters of a mixture model of two lognormal distributions
Dear List,
I have read that a lognormal mixture model having a pdf of the form
f(x)=w1*f1(x)+(1-w1)*f2(x) fits most data sets quite well, where f1
and f2 are lognormal distributions.
Any pointers on how to create a function that would produce the 5
parameters of f(x) would be greatly appreciated.
> version
_
platform i386-pc-mingw32
arch i386
os
2009 May 29
1
Mean of lognormal in base-2
Hi, Does anyone know what the mean value of a lognormal distribution in base-2 is? I am simulating stochastic population growth and if I were working in base-e, I would do:lambda <- 1.1 #multiplicative growth rates <- 0.6 #stochasticity (std. dev)lognormal <- rlnorm(100000, log(lambda) - (s^2)/2, s)## or lognormal <- exp( rnorm( 100000, log(lambda) - (s^2)/2,
2009 Jan 16
3
Fitting of lognormal distribution to lower tail experimental data
Hi,
I am beginner with R and need firm guidance with my problem. I have seen
some other threads discussing the subject of right censored data, but I am
not sure whether or not this problem can be regarded as such.
Data:
I have a vector with laboratory test data (strength of wood specimens,
example attached as txt-file). This data is the full sample. It is a
common view that this kind of data
2010 Dec 27
3
Gamma & Lognormal Model
Dear,
I'm very new to R Gui and I have to make an assignment on Gamma Regressions.
Surfing on the web doesn't help me very much so i hope this forum may be a
step forward.
The question sounds as follows:
The data set is in the library MASS
first install library(MASS)
then type data(mammals)
attach(mammals)
Assignment:
Fit the gamma model and lognormal model for the mammals data.
2006 Aug 05
1
AIC for lognormal model
Dear all,
I want to compare some different models for a dataset by QQ plots and AIC. I get the following AICs:
- linear model: 19759.66
- GAMLSS model: 18702.7
- linear model with lognormal response: -7862.182
The QQ plots show that the lognormal model fits better than the linear model, but still much worse than the GAMLSS. So, in my opinion, the AIC of the lognormal model should be between the
2003 Aug 05
1
error message in fitdistr
Hi R lovers
Here is a numerical vector test
> test
[1] 206 53 124 112 92 77 118 75 48 176 90 74 107 126 99 84 114
147 99 114 99 84 99 99 99 99 99 104 1 159 100 53
[33] 132 82 85 106 136 99 110 82 99 99 89 107 99 68 130 99 99
110 99 95 153 93 136 51 103 95 99 72 99 50 110 37
[65] 102 104 92 90 94 99 76 81 109 91 98 96 104 104 93 99 125
89
2007 Mar 23
1
generating lognormal variables with given correlation
Dear R users
I use simulated data to evaluate a model by sampling the parameters in
my model from lognormal distributions.
I would like these (lognormal distributed) parameters to be correlated,
that is, I would like to have pairwise samples of 2 parameters with a
given correlation coefficient.
I have seen that a covariance matrix can be fixed when generating random
variables from a
2004 Dec 13
1
AIC, glm, lognormal distribution
I'm attempting to do model selection with AIC, using a glm and a lognormal
distribution, but:
fit1<-glm(BA~Year,data=pdat.sp1.65.04, family=gaussian(link="log"))
## gives the same result as either of the following:
fit1<-glm(BA~Year,data=pdat.sp1.65.04, family=gaussian)
fit1<-lm(BA~Year,data=pdat.sp1.65.04)
fit1
#Coefficients:
#(Intercept) Year2004
# -1.6341
2010 Aug 01
2
Lognormal distribution - Range Factor
Hi, What does it mean to say Lognormal distribution with a mean of 1.03E-6
with a range factor of 100 ? How can I find the lognormal distribution
paramters from this information?
Thanks, Tims
[[alternative HTML version deleted]]
2003 Apr 09
3
plotting the lognormal density curve
I am trying to plot a lognormal density curve on top of an existing
histogram. Can anybody suggest a simple way to do this? Even if someone
could just explain how to plot a regular normal density curve on top of an
existing histogram, it would be a big help.
Also, is there some way to search through the R-help archives other than
simple browsing?
Thank you so much. Your help and time is greatly
2001 Dec 21
1
proportional hazard with parametric baseline function: can it be estimated in R
Greetings --
I would like to estimate a proportional hazard model with a weibull or
lognormal baseline. I have looked at both the coxph() and survreg()
functions and neither appear (to me ) to do it. Am I missing something in
the docs or is there another terrific package out there that will do this.
Many Thanks.
Carl Mason
2005 May 03
2
comparing lm(), survreg( ... , dist="gaussian") and survreg( ... , dist="lognormal")
Dear R-Helpers:
I have tried everything I can think of and hope not to appear too foolish
when my error is pointed out to me.
I have some real data (18 points) that look linear on a log-log plot so I
used them for a comparison of lm() and survreg. There are no suspensions.
survreg.df <- data.frame(Cycles=c(2009000, 577000, 145000, 376000, 37000,
979000, 17420000, 71065000, 46397000,
2013 Apr 16
2
Strange error with log-normal models
Hi,
I have some data, that when plotted looks very close to a log-normal distribution. My goal is to build a regression model to test how this variable responds to several independent variables.
To do this, I want to use the fitdistr tool from the MASS package to see how well my data fits the actual distribution, and also build a generalized linear model using the glm command.
The summary