-
Recent Posts

Archives

RSS Links
Feedburner
Blogroll

Meta
DISCLAIMER
The 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 pictures
I 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: number of samples
Polls Apart
Election season is fast approaching so you can be sure a plethora of polls will soon be adding to the mayhem. Polls educate us in two ways. They tell us what we, or at least the population being polled, think. … Continue reading
Posted in Uncategorized
Tagged bias, cats, margin of error, number of samples, politics, polls, population, sample size, samples, statistics, stats with cats, surveys
Leave a comment
Regression Fantasies: Part III
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
Regression Fantasies: Part I
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
Six Misconceptions about Statistics You May Get From Stats 101
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
Posted in Uncategorized
Tagged cats, data scrubbing, math, measurement, number of samples, polls, population, resolution, sample size, samples, statistical analysis, statistics, stats with cats, surveys, uncertainty, variability, variance
8 Comments
Limits of Confusion
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
Posted in Uncategorized
Tagged cats, jargon, number of samples, precision, statistics, stats with cats, t distribution, uncertainty, variability, variance
6 Comments
A Picture Worth 140,000 Words
Even if it’s been a while since your last statistics class, when you read Stats with Cats: The Domesticated Guide to Statistics, Models, Graphs, and Other Breeds of Data Analysis you’ll figure out that there’s much more to data analysis … Continue reading
Grasping at Flaws
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
Posted in Uncategorized
Tagged cats, correlation coefficient, criticism, dependent variable, jargon, math, mean, Normal distribution, number of samples, objectives, population, precision, probability, rule of thumb, sample size, samples, software, statistical analysis, statistical tests, statistics, stats with cats, uncertainty, variability
3 Comments
Secrets of Good Correlations
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
Posted in Uncategorized
Tagged cats, coefficient of determination, correlation coefficient, measurement scales, multiple correlation, number of samples, objectives, outliers, partial correlation, R-square, sample size, shrunken correlation, software, statistical analysis, statistical tests, statistics, stats with cats, trend, variance
9 Comments
Ten Fatal Flaws in Data Analysis
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
Posted in Uncategorized
Tagged cats, extrapolation, information, meaningfulness, measurement scales, model, number of samples, polls, population, precision, resolution, sample size, samples, significance, standardization, statistical analysis, statistical tests, statistics, stats with cats, surveys, uncertainty, variability, variance
34 Comments
It was Professor Plot in the Diagram with a Graph
You probably were taught how to graph data in high school. Depending on your work, you may frequently plot data yourself or look at graphs prepared by others. Even if you don’t use graphs on your job, you may run … Continue reading
Posted in Uncategorized
Tagged axis, cats, charts, diagrams, graphs, jargon, McCandless, measurement scales, number of samples, plots, statistical analysis, statistics, stats with cats, Tufte
2 Comments
