Shouldn't that be "effects"?

Ugh.
You don't understand scientific studies and don't appear to have taken statistics. First, your old blog article uses the word "causes" to describe what is occurring. Wrong. The wording of the Anderson article is "linked", i.e. a correlation, which cannot show causality. Correlations only show when two items occur at the same time, but does NOT show cause and effect.

Additionally, Anderson's area of study is aggression and video games. In scientific study a researcher generally focuses on one area of expertise and does a variety of studies to see where, when, and why certain phenomenon occur over slightly varying conditions.

Interestingly, the science (albeit old) on pay-to-play arcade games showed that if a game was too challenging, people stopped playing them. The rationale behind this is, "why am I paying to fail at the same point"? You could see how this would get expensive if a player was stuck at point x of a game and without intense practice could not pass it. However, once players could practice the difficult parts of a game with a home system with unlimited "tries", play rates skyrocketed.

While this may seem bunk in the business world, secondary data analysis is common in the scientific world. When data is collected, usually only a very small part is being used in the analysis. Other scientists, with permission, can use the data to look at aspects that are of interest to them, but not part of the original study.

The census, for example, provides droves of data to look over. If someone is interested at the ethnic background and educational attainment of the population of a county in North Carolina, they can use the census data to run the analysis. It's not inappropriate, it's just that there is data out there waiting to be analyzed.

That being said, to not know your study is based on a convenience sample is simply inexcusable. As a researcher you should be thoroughly familiar with the data you're using, either you own or a secondary set.

Yes, let us hurl deer at them!

He released a country album a few years ago. It was nominated for a Grammy...wait for it...in the comedy category.

Yes please!

Yes please!

Naptalllica blows.

These things come in handy when dealing with the undead.