Berlin : Heuser, 1894.

Springfield, Virginia : National Technical Information Service, 1986.

Maddalena Cavicchioli.

Source: Electronic Journal of Statistics, Volume 14, Number 1, 605--631.

Abstract:
The paper treats the modeling of stationary multivariate stochastic processes via a frequency domain model expressed in terms of cepstrum theory. The proposed model nests the vector exponential model of [20] as a special case, and extends the generalised cepstral model of [36] to the multivariate setting, answering a question raised by the last authors in their paper. Contemporarily, we extend the notion of generalised autocovariance function of [35] to vector time series. Then we derive explicit matrix formulas connecting generalised cepstral and autocovariance matrices of the process, and prove the consistency and asymptotic properties of the Whittle likelihood estimators of model parameters. Asymptotic theory for the special case of the vector exponential model is a significant addition to the paper of [20]. We also provide a mathematical machinery, based on matrix differentiation, and computational methods to derive our results, which differ significantly from those employed in the univariate case. The utility of the proposed model is illustrated through Monte Carlo simulation from a bivariate process characterized by a high dynamic range, and an empirical application on time varying minimum variance hedge ratios through the second moments of future and spot prices in the corn commodity market.

While President Donald Trump traveled to the battleground state of Arizona this week, his Democratic opponent for the White House, Joe Biden, campaigned from his basement as he has done throughout the coronavirus pandemic. The freeze on in-person campaigning during the outbreak has had an upside for Biden, giving the former vice president more time to court donors and shielding him from on-the-trail gaffes. "I personally would like to see him out more because he's in his element when he's meeting people," said Tom Sacks-Wilner, a fundraiser for Biden who is on the campaign's finance committee.

Barack Obama said the “rule of law is at risk” following the justice department’s decision to drop charges against former Trump advisor Mike Flynn, as he issued a stark warning about the long-term impact on the American way of life by his successor.

Qingyuan Zhao, Jingshu Wang, Wes Spiller, Jack Bowden, Dylan S. Small.

Source: Statistical Science, Volume 34, Number 2, 317--333.

Abstract:
Instrumental variable analysis is a widely used method to estimate causal effects in the presence of unmeasured confounding. When the instruments, exposure and outcome are not measured in the same sample, Angrist and Krueger ( J. Amer. Statist. Assoc. 87 (1992) 328–336) suggested to use two-sample instrumental variable (TSIV) estimators that use sample moments from an instrument-exposure sample and an instrument-outcome sample. However, this method is biased if the two samples are from heterogeneous populations so that the distributions of the instruments are different. In linear structural equation models, we derive a new class of TSIV estimators that are robust to heterogeneous samples under the key assumption that the structural relations in the two samples are the same. The widely used two-sample two-stage least squares estimator belongs to this class. It is generally not asymptotically efficient, although we find that it performs similarly to the optimal TSIV estimator in most practical situations. We then attempt to relax the linearity assumption. We find that, unlike one-sample analyses, the TSIV estimator is not robust to misspecified exposure model. Additionally, to nonparametrically identify the magnitude of the causal effect, the noise in the exposure must have the same distributions in the two samples. However, this assumption is in general untestable because the exposure is not observed in one sample. Nonetheless, we may still identify the sign of the causal effect in the absence of homogeneity of the noise.

Steven Poser
Jun 1, 2003; 23:4420-4427
Cellular

Paper by Mr Luiz Awazu Pereira da Silva, Deputy General Manager of the BIS, Enisse Kharroubi, Emanuel Kohlscheen and Benoît Mojon based on remarks at the University of Basel, 5 May 2019.

Will a nationalist president be undone by his underreaction to a foreign threat?

If you’re feeling awful, you know who to blame.

Well, there’s always the good old “incomplete.”

Always look on the bright side of life.

Suddenly, the White House loves Bernie Sanders.

What this country needs is another group with a very long name.

As the nation unifies, divisiveness falls flat.

1. Some White House staff to wear masks after valet tests positive: Trump  Times of India
2. U.S. President Trump says will be tested for coronavirus daily  The Hindu
3. US VP Mike Pence’s staffer, married to a Trump aide, tests positive for Covid-19  Livemint
4. Trump's U-turn on the coronavirus task force wasn't really a U-turn at all  The Independent
5. Aide to Vice President Pence tests positive for coronavirus  Times of India
6. View Full coverage on Google News

The media is allowing disinformation to appear as news.

He will use deception to keep his bungled response to Covid-19 from ruining his re-election chances.

Trump is Mark Twain’s king, the great American con man.

Documents created by the top disease investigators in the U.S. meant to give step-by-step advice to local leaders deciding when and how to reopen public places such as mass transit, day care centres and restaurants during the still-raging pandemic have been shelved by the Trump administration.

Will he, given his obsession with the economy?

He’s a nominee in perpetual waiting.

He’s not rising to the challenge of the coronavirus pandemic. He’s shriveling into nothingness.

They’re pandemic partners, and that’s double trouble.

The notion that he is bound for four more years is pure superstition.

If the president had listened to the World Health Organization, American lives would have been saved.

Going viral is not a good thing this time.

In what The Spectator calls “the Year of the Drunken Uncle,” three old guys vie for the presidency amid coronavirus fears and a careering stock market.

Beware men who never admit having been wrong.

A pair of model numbers recently discovered in multiple international regulatory filings hinted at a next-generation Beats headphone, but new information suggests the device may actually be related to an existing product that's already in circulation.

Apple is supposedly developing new mental health features for the Apple Watch line that allow the wearable to detect panic attacks, with the capability potentially slated for launch with a next-generation "watchOS 7" this fall.

He says yes. His positions on the issues suggest otherwise.

The nation craves a plan, not hunches.

The president’s failure to understand his limits is very costly.

Are we really going to bet that we can go back to life as normal without proper coronavirus tracking in place?

It will take more care than the president is currently demonstrating to loosen restrictions but still protect the vulnerable.

New OM team members feel encouraged to be an instrument of God in Mexico.

BACKGROUND AND OBJECTIVES:

Children with autism spectrum disorder (ASD) have a higher prevalence of epilepsy compared with general populations. In this pilot study, we prospectively identified baseline risk factors for the development of seizures in individuals with ASD and also identified characteristics sensitive to seizure onset up to 6 years after enrollment in the Autism Speaks Autism Treatment Network.

OBJECTIVES:

Our goals for this study were to characterize the frequency of agitation in patients with autism spectrum disorder (ASD) admitted to an inpatient pediatric medical unit and to identify risk factors associated with agitation.

BACKGROUND AND OBJECTIVES:

Guidelines suggest young children with autism spectrum disorder (ASD) receive intensive nonpharmacologic interventions. Additionally, associated symptoms may be treated with psychotropic medications. Actual intervention use by young children has not been well characterized. Our aim in this study was to describe interventions received by young children (3–6 years old) with ASD. The association with sociodemographic factors was also explored.

CONTEXT:

Recommendations conflict regarding universal application of formal screening instruments in primary care (PC) and PC-like settings for autism spectrum disorder (ASD).

US President Donald Trump has told a town hall meeting that he thinks a coronavirus vaccine will be developed “by the end of this year”.

Mardi Gras in New Orleans has always had a gothic element. The voodoo culture dates from the African American diaspora, though it’s now mostly for tourists. But this year there was an authentically macabre dimension to Fat Tuesday.

Education Week's Andrew Ujifusa hashes out the details of the education budget with Prince George's County, Md., Schools CEO Kevin Maxwell.