=+Variable Coefficient Standard error t-Value Constant $485 384 $257 477 1.89 Independent variable 1: no. of POs $123.22 $57.69 2.14 Independent variable 2: no. of Ss $2 952 $1 476 2.00 r 2

= 0.63; Durbin–Watson statistic = 1.90 Regression 5: PDCs = a + (b1 × No. of POs) + (b2 × No. of Ss) + (b3 × IP$)

Variable Coefficient Standard error t-Value Constant $494 684 $310 205 1.59 Independent variable 1: no. of POs $124.05 $63.49 1.95 Independent variable 2: no. of Ss $2 984 $1 622 1.84 Independent variable 3: IP$ –0.0002 0.0030 –0.07 r 2

= 0.63; Durbin–Watson statistic = 1.90 The coefficients of correlation between combinations of pairs of the variables are:

PDCs IP$ No. of POs IP$ 0.29 No. of POs 0.65 0.27 No. of Ss 0.63 0.34 0.29 Required