Posts Tagged ‘statistics’
Tuesday, December 29th, 2009
How to Use the Product Rule in Algebra
Description
A detailed tutorial on the algebraic product rule. Step by step tutorial including several examples of the algebraic product rule for reference.
Overview
There are many product rules in the world of math. This tutorial focuses on a product rule that is used in algebra and statistics. The product rule states that if two independent tasks T1 and T2 are to be performed, then T1 can be performed m ways and T2 can be performed n ways. Therefore, the number of ways the tasks can be performed together is m * n ways. Remember that this is only the number of possible ways to do something, not how much time it takes to do something. Also, the same method is used no matter how many different tasks you are given.
Tags: algebra, combination, multiplication, multiply, number, permutation, product, rule, statistics, task
Posted in Algebra | No Comments »
Thursday, December 10th, 2009
Overview of Two-Way Counting
Description
A detailed tutorial on two-way counting. Step by step tutorial including several examples of two-way counting for reference.
Overview
Two-way counting is when any expression for a given quantity are determined using two different counting approaches. Many people believe that a quadratic equation is the perfect example of two-way counting, because you find the quantity in more than one way. However, this is incorrect. Two-way counting is actually a backwards method – you have the quantity already, you just need to figure out how you could get it. This is used often in combinations and permutations, where you often already know what quantity you need to have, you just have to figure out how to get there.
Tags: binomial, combination, counting, equation, example, expression, method, permutation, quadratic, quantity, statistics, two, two-way, way
Posted in Statistics | No Comments »
Friday, November 20th, 2009
Definition of an Outlier
Description
A detailed tutorial on the definition of an outlier. Step by step tutorial including several examples of definitions of outliers for reference.
Overview
An outlier is a type of observation of statistical data. It is usually very far away from the other values in the data set, hence the name. Usually it is a number that is much smaller than the other numbers, although it could be much larger than the other numbers as well. Outliers have an equal chance of occuring in any random observation, but they are still rare. Typically when an outlier is found it means there is some sort of mistake, usually a measurement error.
Tags: chance, data, elements, equal, error, larger, measurement, mistake, numbers, observation, outlier, random, set, smaller, statistical, statistics, values
Posted in Statistics | No Comments »
Tuesday, November 17th, 2009
Overview of the Fundamental Counting Principle
Description
A detailed tutorial on the fundamental counting principle. Step by step tutorial including several examples of the fundamental counting principle for reference.
Overview
The fundamental counting principle is a simple method of finding out how many times something occurs. It is a simplified form of finding permutations and combinations, and is used very often in statistics when permutations and combinations must be found. The fundamental counting principle states that if an event can occur in M ways, and another event can occur in N ways, then the first event followed by the second event can occur M * N ways. Basically, if you have two different options, and a different amount of each option, you can multiply them together to find the total number of ways you can combine these options.
Tags: algebra, amount, combinations, combine, counting, fundamental, multiplication, option, permutate, permutations, principle, statistics
Posted in Algebra | No Comments »
Friday, November 13th, 2009
How to Find the Interquartile Range
Description
A detailed tutorial on how to find the interquartile range. Step by step tutorial including several examples of the interquartile range for reference.
Overview
The interquartile range is the range of the data between the lower or first quartile and the upper or third quartile. The interquartile range is not the whole data set – it is actually only half of the data set, although not a common half – the first and last quarter of the data is not included in the interquartile range. To find the interquartile range, all you must do is find all the quartiles, and then find the different between the upper quartile and lower quartile.
Tags: data, First, half, interquartile, lower, median, quarter, quartile, range, second, set, statistics, third, upper
Posted in Statistics | No Comments »
Friday, November 13th, 2009
Definition of a Quartile
Description
A detailed tutorial on the definition of a quartile. Step by step tutorial including several examples of the definition of a quartile for reference.
Overview
A quartile is a value that separates out statistical data. There are three quartiles, and they work together to separate data out into four different parts. The first quartile, called Q1, is the lower quartile. It is the 25th percentile of data – that is, the median of the median of the total amount of data, and the lowest count in a data set. The second quartile, called Q2, is the median of the entire data set. It is sometimes referred to as the middle value. The third quartile, called Q3, is the upper quartile. It is the 75th percentile of data – that is, the median of the median of the total amount of data, and the highest count in a data set.
Tags: 25, 50, 75, data, First, lower, median, middle, parts, percentile, Q1, Q2, Q3, quartile, second, separate, set, statistical, statistics, third, upper
Posted in Statistics | No Comments »
Thursday, November 12th, 2009
How to Make a Histogram
Description
A detailed tutorial on how to make a histogram. Step by step tutorial including several examples on how to make a histogram for reference.
Overview
A histogram is similar to a bar chart or bar graph, only it cannot go in either direction – histograms can only have vertical bars. The main difference between them is that bar charts and bar graphs can be used to show the number of items in a category. Histograms are used between two sets of numbers, to show which numbers relate to each other. The numbers themselves each fall under their own category. This is a very common chart to see in the later levels of math, especially statistics, as they reflect statistical data.
Tags: algebra, bar, category, chart, data, difference, graph, histogram, horizontal, number, relationship, set, statistics, vertical
Posted in Algebra | No Comments »
Thursday, November 12th, 2009
Introduction to the Margin of Error
Description
A detailed tutorial on the margin of error. Step by step tutorial including several examples of the margin of error for reference.
Overview
The margin of error is a statistic that expresses the amount of possible random sampling errors that could end up in the result of a survey. The bigger the margin of error, the less trustworthy the survey is, because it means that everything falling within the margin of error could possibly be wrong and not accurate. However, if the margin or error is small, then the survey should be very accurate.
Tags: accuracy, accurate, error, less, margin, more, random, results, right, sampling, statistics, survey, true, trustworthy, wrong
Posted in Statistics | No Comments »
Tuesday, November 10th, 2009
How to Make a Stem-and-Leaf Plot
Description
A detailed tutorial on how to make a stem-and-leaf plot. Step by step tutorial including several examples of how to make a stem-and-leaf plot for reference.
Overview
A stem-and-leaf plot is named for it’s resemblance to a tree branch. The bar down the middle is the branch, and the numbers on either side are the leaves on the branch. Like box-and-whisker plots, stem-and-leaf plots are used to organize statistical data. There should be one number on the left side of the bar, and that number should be the number in the ten’s place. If it is only a one digit number, that number should be zero. If it is a three digit number, then put two numbers on the left. Then you have the bar. On the right side of the bar, are all the numbers that are found in the hundred’s place, put once again in order of smallest to largest. They will all appear in the row with with the matching number in the ten’s place.
Tags: algebra, bar, hundreds, leaf, number, organize, place, plot, row, statistics, stem, stem-and-leaf, stemplot, tens
Posted in Algebra | No Comments »
Thursday, October 8th, 2009
Inverse Variation Explained
Description
A detailed tutorial on inverse variation. Step by step tutorial including several examples of inverse variation and what inverse variation is for reference.
Overview
Inverse variation states that two variables are inversely proportional if one of the variables is directly proportional with the multiplicative inverse of the other, or equivilently if their product is a constant. Inverse variation can be expressed mathematically as y = k / x, where x and y are the variables and k is a nonzero constant
Tags: constant, direct, division, inverse, k, Math, multiplicative inverse, non-zero, proportionality, reciprocal, statistics, variable, variation, x, y
Posted in Statistics | No Comments »
