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Tag Archives: Mean
Looking at Spread
In the previous post Two Statisticians in a Battlefield, we discussed the importance of reporting a spread in addition to an average when describing data. In this post we look at three specific notions of spread. They are measures that … Continue reading
Two Statisticians in a Battlefield
Two soldiers, both statisticians, were fighting side by side in a battlefield. They spotted an enemy soldier and they both fired their rifles. One statistician soldier fired one foot to the left of the enemy soldier and the other statistician … Continue reading
The Tax Return of Mitt Romney
Mitt Romney is currently a candidate for the 2012 Republican Party nomination for U.S. President. He recently, bowed to pressure from another presidential candidate in the Republican Party, had to release his past tax returns. The release of these tax … Continue reading
Another Look at LA Rainfall
In two previous posts, we examined the annual rainfall data in Los Angeles (see Looking at LA Rainfall Data and LA Rainfall Time Plot). The data we examined in these two post contain 132 years worth of annual rainfall data … Continue reading
Comparing Growth Charts
Suppose both an 8year old boy and a 10year old boy are 54 inches tall (four feet six inches). Physically they are of the same heights. But a better way to compare is to find out where each boy stands … Continue reading
Interpreting ACT Scores
The ACT is a standardized test that is used for college and university admissions in the United States. According to their web site, the ACT test “assesses high school students’ general educational development and their ability to complete collegelevel work”. … Continue reading
The Safest Driving City in America
Which city in America has the worst drivers? When I asked this questions, many people guessed New York or Los Angeles. How about the city with the safest drivers? According to a recent report released by The Allstate Insurance Company, … Continue reading
Choosing a High School
Many parents try to find the best high school for their children. Many variables are usually involved in choosing a school. One criterion is to look at successes of the graduates of a school. One measure of success may be … Continue reading
LA Rainfall Time Plot
In a previous post, we had an elementary look at the seasonal rainfall data in Los Angeles, California, using graphs (histograms) and numerical summaries to describe the data. The rainfall data were collected over time (total rainfall in inches over … Continue reading
A Student’s View of the Normal Distribution
In my teaching, I always strive to encourage students to look at statistics from a practical point of view. In a recent class period covering the normal distribution, I indicated that data values more than 3 standard deviations away from … Continue reading →