Using a Calculator for Statistics
Casio fx-82MS
Mean and Standard deviation
1. Turn calculator on! [ON]
2. Put into Statistical Mode [MODE][2]
3. Clear the statistical memory [SHIFT][CLR][1][=]
([CLR] is next to [ON])
[STAT CLEAR shows on the screen – you can enter data now]
(Clear the statistical memory each time you have a new data set to work with –
very important!)
4. To enter data key in each piece of data then press [M+]
For example, to enter (18, 23, 20, 21, 24, 23, 21, 21, 15, 19, 24)
18 [M+] 23 [M+] 20 [M+] 21 [M+] 24 [M+] 23 [M+] 21 [M+] 21 [M+] 15 [M+] 19 [M+] 24
[M+]
5. n (the number of pieces of data) is shown on the screen
6. To find the mean ( x ): [SHIFT][2][1][=]
(11)
(20.82 (2dp))
7. To find the standard deviation:
[SHIFT][2][2][=] (σ) if the data is from a population
[SHIFT][2][3][=] (s or σ n1 ) if the data is from a sample
(2.62 (2dp))
(2.75 (2dp))
8. To enter grouped data: key in each piece of data then press [SHIFT] [,] frequency
[M+]
([,] is on the left of [M+])
For example
Frequency Table for the number of faults in a component
Number of Faults
Frequency
0
28
1
11
2
4
0[SHIFT][,]28[M+]
1[SHIFT][,]11[M+]
2[SHIFT][,]4[M+]
For this data n = 43, mean ( x )= 0.44, sample standard deviation (s or σ n1 ) = 0.67
To find x 2 , x, or n; press [SHIFT] [1] then choose the appropriate statistic
Unitec: D:\308870190.doc
Correlation / Linear Regression Calculations
1. Turn calculator on! [ON]
2. Put into Regression Mode [MODE][3]
3. Choose linear regression [1]
4. Clear the statistical memory [SHIFT][MODE] [=] ([CLR] is next to [ON])
(do this each time you have a new data set to work with – very important!)
5. To enter data, key in x variable [,] y variable [M+]
([,] is on the left of [M+])
For example, to enter data in this table
x variable
5
8
12
y variable
100
118
124
5 [,]100 [M+] 8 [,] 118 [M+] 12 [,] 124 [M+]
For all regression statistics key [SHIFT][2] – S-VAR
When you press this key you may not be able to see what you require – you
must scroll along with the big replay key in the centre of the calculator to see
the statistic before you key in its number
You must key [AC] between each statistic
6. To find r (the correlation co-efficient): [SHIFT] [2] [3] [=]
(0.935)
7. To find r² (the co-efficient of determination) square r
(0.874)
8. To find the linear regression equation y = a + bx
[SHIFT] [2 ] [1] [=] for a
[SHIFT] [2] [2] [=] for b
(86.297)
(3.324)
9. To predict y from your regression equation: ŷ
Key in x value say [9] and then [SHIFT] [2] scroll [2] ŷ [=]
(If x = 9, y = 116.2)
Unitec: D:\308870190.doc
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