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Statistical data can by typed in by hand, or imported as a text file. This makes it possible to use data from the internet or data logging devices connected to temperature probes and the like.

Here are the options available for graphing and calculating statistics in Maths Helper Plus...

 Data Tables

You decide what columns to include in your data table. You can click buttons to plot cumulative frequency or cumulative percentage values.

This table has all possible columns shown:

 xÂ  fÂ  x²Â  fxÂ Â  fx²Â  cum.fÂ  cum.%Â  rel.fÂ Â Â Â Â  z score 1Â  2Â  1Â Â  2Â Â Â  2Â Â Â  2Â Â Â Â Â  6.452Â  0.0645161Â  -1.7599 2Â  3Â  4Â Â  6Â Â Â  12Â Â  5Â Â Â Â Â  16.13Â  0.0967742Â  -1.25938 3Â  5Â  9Â Â  15Â Â  45Â Â  10Â Â Â Â  32.26Â  0.16129Â Â Â  -0.758855 4Â  6Â  16Â  24Â Â  96Â Â  16Â Â Â Â  51.61Â  0.193548Â Â  -0.258333 5Â  6Â  25Â  30Â Â  150Â  22Â Â Â Â  70.97Â  0.193548Â Â  0.242188 6Â  4Â  36Â  24Â Â  144Â  26Â Â Â Â  83.87Â  0.129032Â Â  0.742709 7Â  2Â  49Â  14Â Â  98Â Â  28Â Â Â Â  90.32Â  0.0645161Â  1.24323 8Â  2Â  64Â  16Â Â  128Â  30Â Â Â Â  96.77Â  0.0645161Â  1.74375 9Â  1Â  81Â  9Â Â Â  81Â Â  31Â Â Â Â  100Â Â Â  0.0322581Â  2.24427 totals: Â Â  31 140 756Â  1

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 Calculations

The following statistics calculated, and all working steps are displayed if required:

mode, mean, median, range,Â
sample standard deviation, sample variance,
population standard deviation, population variance,
five number summary with outliers rejected,
inter quartile range.

Here are the working steps displayed by Maths Helper Plus for some sample statistics:

 MODE = score with the highest frequency There are 2 modal scores with f = 6: Â Â  x = 4 Â Â  and 5 MEAN = sum of scores / number of scores Â Â Â Â  = sum of 'fx' / sum of 'f' Â Â Â Â  = 140 / 31 Â Â Â Â  = 4.51613 MEDIAN = middle score Â n = 31, which is ODD Â So the median is at position (31+1)/2 = 16. Â The median score = 4 RANGE = maximum score - minimum score Â Â Â Â Â  = 9 - 1 Â Â Â Â Â  = 8 STANDARD DEVIATION Â sd (population) = sqrt[ (sum of fx²/n) - (sum of fx)/n)² ] Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  = sqrt[ (756/31) - (140/31)² ] Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  = 1.99792 VARIANCE Â var (population) = (sum of fx²/n) - (sum of (fx)/n)² Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  = (756/31) - (140/31)² Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  = 1.99792 FIVE NUMBER SUMMARY (Tukey's Method) Â Step 1: Find the median: Q2 Â (See the 'median' option for this procedure) Â Q2 = 4 Â There are 31 values, which is an ODD number. Â Split the data into two halves, each including the median. Â Q1 is the median of the lower half, Â and Q3 is the median of the upper half. Step 2: Find the first quartile: Q1 Â There are 16 scores less or equal to the median. Â This is an EVEN number, so Q1 is the average of scores Â at positions: 16/2 = 8 and 8 + 1 = 9. Â The score at position 8 is x = 3, Â and the score at position 9 is x = 3. Â So Q1 = [3 + 3]/2 Â Â Â Â Â Â Â Â Â Â  = 3 Step 3: Find the third quartile: Q3 There are also 16 scores greater or equal to the median. so Q3 is the average of scores at positions: 16 + 16/2 = 24 and 24 + 1 = 25. The score at position 24 is x = 6, and the score at position 25 is x = 6. So Q3 = [6 + 6]/2 Â Â Â Â Â Â Â Â Â  = 6 Step 4: Find the minimum and maximum acceptable scores [Scores more than 1.5 times the interquartile range (IQR) below Q1 or above Q3 are rejected as outliers.] 1.5 × IQR = 1.5 × 3 = 4.5 so the lowest acceptable score = 3 - 4.5 = -1.5, and the highest acceptable score = 6 + 4.5 = 10.5 Rejecting scores outside these limits: min = 1, Q1 = 3, Q2 = 4, Q3 = 6, max = 9 INTERQUARTILE RANGE = Q3 - Q1 = 6 - 3 = 3

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 Classes

Specify class intervals to apply to your raw data by typing three numbers in the white edit boxes of this dialog box:

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Once applied to your data, all statistical calculations use the class midpoint values only. Classes are also included in the data tables.

 Histogram, Frequency Polygon

There are an incredible range of options for displaying histograms and frequency polygons:

 Stem & Leaf, Box & Whisker

Maths Helper Plus provides a comprehensive range of options for creating 'Stem-and-leaf' and box plots.Â
This dialog box is used to select the required options:

Here is a stem & leaf plot created with Maths Helper Plus:

STEM AND LEAF PLOT:
Unit = 1, Example: 1 | 2 represents 12

Â  0* | 1 1
Â  T | 2 2 2 3 3 3 3 3
Â  F | 4 4 4 4 4 4 5 5 5 5 5 5
Â  S | 6 6 6 6 7 7
Â  . | 8 8 9

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