Error bars illustrate the margin of error for a survey estimate by showing how precise that estimate is. Here are some answers to common questions that might help you better understand charts with ...

When we look in the mirror, it’s easy to see not only the physical attributes that define our unique features, but also the layers beneath that makeup who we are — those tired eyes given as a gift of ...

A behind-the-scenes blog about research methods at Pew Research Center. For our latest findings, visit pewresearch.org. Academic survey researchers tend to differ ...

General results are obtained for an approximation to the variance of a weighted regression estimator in which the weights are sample estimators of unknown unpatterned variances. Independent normally ...

If you asked one person their voting intention and they replied "Labour" you would not infer that the country is full of lefties, but rather that you have too small a sample. Similarly, if you see an ...

Sampling oscilloscopes are often used to measure jitter in gigahertz-rate optical signals. With bit rates that high, errors in an oscilloscope's time base can add jitter to a viewed signal. Engineers ...