Te Puna Ako Learning Centre Casio fx-82TL – mean, standard deviation, regression Mean and Standard Deviation 1. Turn calculator on! [AC/ON] 2. Put into statistical mode [MODE] [2] 3. Clear the statistical memory [SHIFT] [AC/ON] [=] (do this 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. To find n (the number of pieces of data): [RCL] [hyp] (11) 6. To find the mean ( x ): [SHIFT] [1] [=] (20.82 (2dp) 7. To find the standard deviation: [SHIFT] [2] [=] (σ) if the data is from a population [SHIFT] [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] [,] i.e. the ; then frequency [M+] ([,] is on the left of [M+]) For example (from a sample of 43) 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 Unitec: D:\308872093.doc Correlation / Linear Regression 1. Turn calculator on! [AC/ON] 2. Put into Regression Mode [MODE][3] 3. Choose linear regression [1] 4. Clear the statistical memory [SHIFT][AC/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+] 6. To find r (the correlation co-efficient): [SHIFT] [(] [=] (r is above the left bracket) 7. To find r² (the co-efficient of determination) square r 8. To find the linear regression equation y = bx + a [SHIFT] [7] [=] for a [SHIFT] [8] [=] for b 9. To predict y from your regression equation: ŷ Key in x value and then [SHIFT] [-] Unitec: D:\308872093.doc (0.93) (0.87) (86.3) (3.3) (If x = 9, y = 116.2)