Displaying 9 results from an estimated 9 matches for "sigma_a".
Did you mean:
sigma_j
2017 Nov 21
2
Do I need to transform backtest returns before using pbo (probability of backtest overfitting) package functions?
...3/252 i.e. an ANNUAL 3% rate converted
to a DAILY rate, expressed in decimal.
That means that the other argument to this function, x, should be DAILY
returns, expressed in decimal.
Suppose he wanted to create random data from a distribution of returns with
ANNUAL mean MU_A and ANNUAL std deviation SIGMA_A, both stated in decimal.
The equivalent DAILY returns would have mean MU_D = MU_A / 252 and standard
deviation SIGMA_D = SIGMA_A/SQRT(252).
He calls MU_D by the name mu_base and SIGMA_D by the name sigma_base.
His loop now converts the random numbers in his matrix so that each column
has mean...
2017 Nov 21
0
Do I need to transform backtest returns before using pbo (probability of backtest overfitting) package functions?
...converted
> to a DAILY rate, expressed in decimal.
> That means that the other argument to this function, x, should be DAILY
> returns, expressed in decimal.
>
> Suppose he wanted to create random data from a distribution of returns
> with ANNUAL mean MU_A and ANNUAL std deviation SIGMA_A, both stated in
> decimal.
> The equivalent DAILY returns would have mean MU_D = MU_A / 252 and
> standard deviation SIGMA_D = SIGMA_A/SQRT(252).
>
> He calls MU_D by the name mu_base and SIGMA_D by the name sigma_base.
>
> His loop now converts the random numbers in his mat...
2017 Nov 21
1
Do I need to transform backtest returns before using pbo (probability of backtest overfitting) package functions?
...e converted to a DAILY rate, expressed in decimal.
>> That means that the other argument to this function, x, should be DAILY returns, expressed in decimal.
>>
>> Suppose he wanted to create random data from a distribution of returns with ANNUAL mean MU_A and ANNUAL std deviation SIGMA_A, both stated in decimal.
>> The equivalent DAILY returns would have mean MU_D = MU_A / 252 and standard deviation SIGMA_D = SIGMA_A/SQRT(252).
>>
>> He calls MU_D by the name mu_base and SIGMA_D by the name sigma_base.
>>
>> His loop now converts the random numbe...
2012 Feb 02
0
glmer question
I would like to fit the following model:
logit(p_{ij}) = \mu + a_i + b_j
where a_i ~ N(0, \sigma_a^2) , b_j ~ N(0, \sigma_b^2) and \sigma_a
= \sigma_b.
Is it possible to fit a model with such a constraint on the variance
components in glmer?
--
View this message in context: http://r.789695.n4.nabble.com/glmer-question-tp4351829p4351829.html
Sent from the R help mailing list archive at Na...
2017 Nov 21
0
Do I need to transform backtest returns before using pbo (probability of backtest overfitting) package functions?
...3/252 i.e. an ANNUAL 3% rate converted
to a DAILY rate, expressed in decimal.
That means that the other argument to this function, x, should be DAILY
returns, expressed in decimal.
Suppose he wanted to create random data from a distribution of returns with
ANNUAL mean MU_A and ANNUAL std deviation SIGMA_A, both stated in decimal.
The equivalent DAILY
Then he does two steps: (1) generate a matrix of random values from the
N(0,1) distribution. (2) convert them to DAILY
After initializing the matrix with random values (from N(0,1)), he now
wants to create a series of DAILY
sr_base <- 0
mu_base <...
2006 Oct 24
1
Variance Component/ICC Confidence Intervals via Bootstrap or Jackknife
...But the few references I've been able to track down (Arvesen, Biometrcs,
1970 is one), seem to say that I should just sample with replacement the
i units. Plus they seem to indicate that a log transform is needed. The
Arvesen reference used something like using log(v_a/v_e) as an estimator
for sigma_a^2/sigma_e^2 and getting an interval and then transforming to
get to an interval for the ICC (although it's not clear to me how to get
the other ICC in a two-level nested design).
Any insights would be appreciated.
Rick B.
2017 Nov 21
2
Do I need to transform backtest returns before using pbo (probability of backtest overfitting) package functions?
Wrong list.
Post on r-sig-finance instead.
Cheers,
Bert
On Nov 20, 2017 11:25 PM, "Joe O" <joerodonnell at gmail.com> wrote:
Hello,
I'm trying to understand how to use the pbo package by looking at a
vignette. I'm curious about a part of the vignette that creates simulated
returns data. The package author transforms his simulated returns in a way
that I'm
2005 Mar 26
5
PCA - princomp can only be used with more units than variables
Hi all:
I am trying to do PCA on the following matrix.
N1 N2 A1 A2 B1 B2
gene_a 90 110 190 210 290 310
gene_b 190 210 390 410 590 610
gene_c 90 110 110 90 120 80
gene_d 200 100 400 90 600 200
>dataf<-read.table("matrix")
>
2008 Aug 29
3
extract variance components
HI,
I would like to extract the variance components estimation in lme function
like
a.fit<-lme(distance~age, data=aaa, random=~day/subject)
There should be three variances \sigma_day, \sigma_{day %in% subject } and
\sigma_e.
I can extract the \sigma_e using something like a.fit$var. However, I cannot
manage to extract the first two variance components. I can only see the
results in