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: trend
Is Your Regression Model Telling the Truth? There are many technologies we use in our lives without really understanding how they work. Television. Computers. Cell phones. Microwave ovens. Cars. Even many things about the human body are not well understood. … Continue reading
Five Common Reasons for Doubting a Regression Model Finding a model that fits a set of data is one of the most common goals in data analysis. Least squares regression is the most commonly used tool for achieving this goal. … 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
If you’ve ever seen a correlation coefficient, you’ve probably looked at the number and wondered, is that good? Is a correlation of -0.73 good but not a correlation of +0.58? Just what is a good correlation and what makes a … Continue reading
Fifty Ways to Fix your Data (Sing to the tune of “Fifty Ways to Leave Your Lover” by Paul Simon) The problem is all about your scales, she said to me The R-squares will be better if you’ve matched ’em … Continue reading
No matter what their area of expertise, statisticians are asked certain questions with such predictability that it borders on the deterministic. No question is asked more often than: How many samples do I need? Most statisticians wish they could answer … Continue reading
We are all awash in statistics. Every day, we see the probability of precipitation, the results of opinion polls, changes in the stock market, your grades in school, or the batting average of the baseball team you follow. It’s surprising, … Continue reading
When you were in school, you probably asked the question, why do I have to take statistics?” Your adviser told you: “because it’s required for the degree.” “But why,” you said “why would I ever need to use statistics?” Everybody … Continue reading
Stats With Cats is a great companion to any introductory textbook in statistics. You won’t find a lot of equations or descriptions of the central limit theorem, probability, and hypothesis testing. You can find that information in traditional statistical texts. … Continue reading