Diseases, Conditions, Syndromes

EXPLAINER: What we know and don't know about omicron variant

The World Health Organization says it could still take some time to get a full picture of the threat posed by omicron, a new variant of the coronavirus as scientists worldwide scramble to assess its multiple mutations.

Diseases, Conditions, Syndromes

WHO hosts special meeting on worrying new COVID-19 variant

Advisers to the World Health Organization are holding a special session Friday to flesh out information about a worrying new variant of the coronavirus that has been detected in South Africa, though a top expert says its ...

Neuroscience

Brain activity foreshadows changes in stock prices

Forecasting changes in stock prices may be possible with the help of brain activity in regions associated with how people feel before making investment choices. Scientists could accurately forecast market price changes based ...

Vaccination

Vaccine innovation sparks hope, questions

Reports that one of the vaccines for COVID-19 has shown highly promising results are a ray of hope for a world in the shadow of surging virus cases.

Diseases, Conditions, Syndromes

Knowing the model you can trust: The key to better decision-making

As much of Europe is engulfed by a second wave of COVID-19, and track and trace struggles to meet demand, modeling support tools are being increasingly used by policymakers to make key decisions. Most notably, models have ...

Vaccination

Investors pan for gold in rush for coronavirus vaccine

With the race on to find a coronavirus vaccine, the biotech sector—from an investor's point of view—appears to be the new gold rush, promising often giddy returns, but analysts warn that the exuberance could be exaggerated.

Psychology & Psychiatry

Best ways to help kids through the pandemic

They're not at school. They miss their friends. And Mom and Dad look worried. Lockdown during the coronavirus pandemic can take a toll on everyone, especially kids.

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Stock market

A stock market is a public market for the trading of company stock and derivatives at an agreed price; these are securities listed on a stock exchange as well as those only traded privately.

The size of the world stock market was estimated at about $36.6 trillion US at the beginning of October 2008. The total world derivatives market has been estimated at about $791 trillion face or nominal value, 11 times the size of the entire world economy. The value of the derivatives market, because it is stated in terms of notional values, cannot be directly compared to a stock or a fixed income security, which traditionally refers to an actual value. Moreover, the vast majority of derivatives 'cancel' each other out (i.e., a derivative 'bet' on an event occurring is offset by a comparable derivative 'bet' on the event not occurring.). Many such relatively illiquid securities are valued as marked to model, rather than an actual market price.

The stocks are listed and traded on stock exchanges which are entities of a corporation or mutual organization specialized in the business of bringing buyers and sellers of the organizations to a listing of stocks and securities together. The stock market in the United States includes the trading of all securities listed on the NYSE Euronext, the NASDAQ, the Amex, as well as on the many regional exchanges, e.g. OTCBB and Pink Sheets. European examples of stock exchanges include the London Stock Exchange, the Deutsche Börse.

This text uses material from Wikipedia, licensed under CC BY-SA