DISCLAIMERThe postings on this blog are my own (except as noted) and do not necessarily represent the positions, strategies or opinions of my current, past, and future employers, cats and other family members, relatives, Facebook friends, real friends, Charlie Sheen, people who sit next to me on public transportation, or myself when I’m in my right mind.
About picturesI decided to start using other peoples' pictures of cats for my blogs for a variety of reasons. It's hard enough for me to get a good picture of my cats let alone one that might go with what I'm writing. I also thought it would improve my blogs by having a much greater variety of images to choose from. I understand enough about creativity and art and photography to know they are both a talent and a skill that should be recognized. I want to give proper attribution to the creators of the images I use in my blogs, but there is a problem. Virtually every image I want to use appears in more than one place on the Internet. I thought using tineye.com, a search site for finding URLs of uploaded images, would help. In fact, I found the opposite. Some of the images I've searched for are found on a hundred different sites, making it impossible to identify the original. So, if I can't identify the original, I'll cite the site I got the image from or if it's an image I don't have a URL for, I'll cite the site that tineye.com indicates has the image that most closely matches the image I use. If I use an image that you created and I didn’t give you credit, I'm sorry. Let me know and I’ll fix the citation or remove the image.
Tag Archives: uncertainty
Of the over two million college degrees that are granted in the U.S. every year, including those earned at accredited online colleges nationwide, probably two-thirds require completion of a statistics class. That’s over a million and a half students taking … Continue reading
Scientists and other theory-driven data analysts focus on eliminating bias and maximizing accuracy so they can find trends and patterns in their data. That’s necessary for any type of data analysis. For statisticians, though, the real enemy in the battle … Continue reading
When you learn new things, you can develop misconceptions. Maybe it’s the result of something you didn’t understand correctly. Maybe it’s the way the instructor explains something. Or maybe, it’s something unspoken, something you assume or infer from what was … Continue reading
Whether you took or are taking an introductory course on statistics, you probably didn’t get to choose from a dozen candidate offerings. You had to take the specific course required for your major. You can, though, evaluate what you got. … Continue reading
A confidence interval is the numerical interval around the mean of a sample from a population that has a certain confidence of including the mean of the entire population. “Say what?” OK, let’s take it one point at a time. … Continue reading
Even if you’re not a statistician, you may one day find yourself in the position of reviewing a statistical analysis that was done by someone else. It may be an associate, someone who works for you, or even a competitor. … Continue reading
The process of developing a statistical model (http://statswithcats.wordpress.com/2010/12/04/many-paths-lead-to-models/) involves finding the mathematical equation of a line, curve, or other pattern that faithfully represents the data with the least amount of error (i.e., variability). Variability and pattern are the yin and … Continue reading
The most carefully planned data analysis may not survive the intervention of a boss (or a client or other reviewer), whether well intentioned or not. Your aim may be to generate sound data and conduct a thorough and valid analysis, … Continue reading
1. Where’s the Beef? In a way, the worst flaw a data analysis can have is no analysis at all. Instead, you get data lists, sorts and queries, and maybe some simple descriptive statistics but nothing that addresses objectives, answers … Continue reading
You can’t understand your data unless you control extraneous variance attributable to the way you select samples, the way you measure variable values, and any influences of the environment in which you are working. Using the concepts of reference, replication … Continue reading