Article ID: 2

Added: January 10, 2008

Category: Calculator

Question: Can you explain those Stats terms used in KeyPlus?

I want to use statistics functions in Scientific Calculator, but I don't understand what those terms are. I don't know what "sample size" is, and I don't have any clue about "standard deviation." Can you explain those terms as it appears on Statistics review list?

Answer

The BrailleNote User Guide chapter on Scientific Calculator/Stats section explains statistical terms. For convenience, here is the breakdown of meaning of stats terms, as it appears in Stats review list (S command from Calculator):

• Sample Size: the number of entries entered on Data Set list, usually denoted by letter N. Sample size merely means number of subjects, number of people surveyed, etc.
• Mean: this frequently used term means the average of the all values. This can be found by adding all values and dividing it by number of sample size, or entries.
• Median: a median is a number that divides the values in a data set into two groups: the lower half and upper half. In simple words, median is the middle number.
• Mode: A mode is the value that occurs the most in a given data set.
• Minimum and Maximum: the minimum is the lowest value, and maximum is the highest.
• Standard Deviation: a standard deviation measures variability, or spread of values from its mean. In other words, standard deviation measures the distance of one value from the mean. One standard deviation means that a value is "... this far from mean." There are two types: sample standard deviation, denoted by letter s (this measures the values within sample, a part of the population), and population standard deviation, denoted by the Greek letter sigma (where the whole population is measured).
• Sum of values and squares: the sum of values is the result that can be obtained by adding all values in the data set; likewise, sum of squares is the result that can be found by squaring each value, e.g. 8 squared equals 64 and adding them together. This is used to find variance in data set - the measurement of difference between one value to the next.

Updated: February 25, 2008