1 NIST/ITL StRD 2 Dataset Name: Thurber (Thurber.dat) 3 4 File Format: ASCII 5 Starting Values (lines 41 to 47) 6 Certified Values (lines 41 to 52) 7 Data (lines 61 to 97) 8 9 Procedure: Nonlinear Least Squares Regression 10 11 Description: These data are the result of a NIST study involving 12 semiconductor electron mobility. The response 13 variable is a measure of electron mobility, and the 14 predictor variable is the natural log of the density. 15 16 17 Reference: Thurber, R., NIST (197?). 18 Semiconductor electron mobility modeling. 19 20 21 22 23 24 25 Data: 1 Response Variable (y = electron mobility) 26 1 Predictor Variable (x = log[density]) 27 37 Observations 28 Higher Level of Difficulty 29 Observed Data 30 31 Model: Rational Class (cubic/cubic) 32 7 Parameters (b1 to b7) 33 34 y = (b1 + b2*x + b3*x**2 + b4*x**3) / 35 (1 + b5*x + b6*x**2 + b7*x**3) + e 36 37 38 Starting Values Certified Values 39 40 Start 1 Start 2 Parameter Standard Deviation 41 b1 = 1000 1300 1.2881396800E+03 4.6647963344E+00 42 b2 = 1000 1500 1.4910792535E+03 3.9571156086E+01 43 b3 = 400 500 5.8323836877E+02 2.8698696102E+01 44 b4 = 40 75 7.5416644291E+01 5.5675370270E+00 45 b5 = 0.7 1 9.6629502864E-01 3.1333340687E-02 46 b6 = 0.3 0.4 3.9797285797E-01 1.4984928198E-02 47 b7 = 0.03 0.05 4.9727297349E-02 6.5842344623E-03 48 49 Residual Sum of Squares: 5.6427082397E+03 50 Residual Standard Deviation: 1.3714600784E+01 51 Degrees of Freedom: 30 52 Number of Observations: 37 53 54 55 56 57 58 59 60 Data: y x 61 80.574E0 -3.067E0 62 84.248E0 -2.981E0 63 87.264E0 -2.921E0 64 87.195E0 -2.912E0 65 89.076E0 -2.840E0 66 89.608E0 -2.797E0 67 89.868E0 -2.702E0 68 90.101E0 -2.699E0 69 92.405E0 -2.633E0 70 95.854E0 -2.481E0 71 100.696E0 -2.363E0 72 101.060E0 -2.322E0 73 401.672E0 -1.501E0 74 390.724E0 -1.460E0 75 567.534E0 -1.274E0 76 635.316E0 -1.212E0 77 733.054E0 -1.100E0 78 759.087E0 -1.046E0 79 894.206E0 -0.915E0 80 990.785E0 -0.714E0 81 1090.109E0 -0.566E0 82 1080.914E0 -0.545E0 83 1122.643E0 -0.400E0 84 1178.351E0 -0.309E0 85 1260.531E0 -0.109E0 86 1273.514E0 -0.103E0 87 1288.339E0 0.010E0 88 1327.543E0 0.119E0 89 1353.863E0 0.377E0 90 1414.509E0 0.790E0 91 1425.208E0 0.963E0 92 1421.384E0 1.006E0 93 1442.962E0 1.115E0 94 1464.350E0 1.572E0 95 1468.705E0 1.841E0 96 1447.894E0 2.047E0 97 1457.628E0 2.200E0 98
