Question: Transistor gain between emitter and collector in
Transistor gain between emitter and collector in an integrated circuit device (hFE) is related to two variables (Myers, Montgomery and Anderson-Cook, 2009) that can be controlled at the deposition process, emitter drive-in time (x1, in minutes) and emitter dose (x2, in ions × 1014). Fourteen samples were observed following deposition, and the resulting data are shown in the table below. We will consider linear regression models using gain as the response and emitter drive-in time or emitter dose as the regressor variable. 
(a) Determine if emitter drive-in time influences gain in a linear relationship. That is, test H0: β1 = 0, where β1 is the slope of the regressor variable. (b) Do a lack-of-fit test to determine if the linear relationship is adequate. Draw conclusions. (c) Determine if emitter dose influences gain in a linear relationship. Which regressor variable is the better predictor of gain?
Transcribed Image Text:
y (gain, Obs. time, min) ions x1014) or hFE) 1004 1636 852 1506 a1 (drive-in r2 (dose, 1 195 4.00 4.00 4.60 2 255 3 195 4 255 4.60 255 4.20 1272 6 255 4.10 1270 255 4.60 1269 903 7 8 195 255 4.30 4.30 1555 10 255 4.00 1260 11 255 4.70 1146 1276 1225 12 255 4.30 13 255 4.72 4.30 14 340 1321
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