***************************************************************************** * CHAPTER 6 - STATISTICS FOR BUSINESS & ECONOMICS, 4th Ed., by Paul Newbold * ***************************************************************************** * * Example 6.1, page 228 * * The SAMPLE command is used to specify the sample range of the data to be * read. The READ command inputs the data and assigns variable names. In * this case, the years of experience for six employees is assigned EXPER. * The LIST option on the READ command lists all data read. * SAMPLE 1 6 READ EXPER / LIST 2 4 6 6 7 8 * * The STAT command is used to calculate the mean experience of the six * employees in years on the job. * STAT EXPER * DELETE / ALL * *---------------------------------------------------------------------------- * Example 6.2, page 231 * * The Mean and Standard Deviation of the annual percentage salary increase * for the CEO of all mid-size corporations is defined as MEANX and SIGMAX. * The random sample is defined as N. * GEN1 MEANX=12.2 GEN1 SIGMAX=3.6 GEN1 N=9 * * The GEN1 command is used to calculate the standard error of the sampling * distribution of the sample mean. * GEN1 SIGMAMX=SIGMAX/SQRT(N) PRINT SIGMAMX * * The probability that the sample mean will be less than 10% is: * GEN1 PZ=(10-MEANX)/SIGMAMX PRINT PZ * * From Table 3 of the Appendix, Fz(1.83)=0.9664 * GEN1 FZ=0.9664 GEN1 PMEANX=1-FZ PRINT PMEANX * DELETE / ALL * *---------------------------------------------------------------------------- * Example 6.3, page 232 * * The mean life of spark plugs is defined as MEANX, standard deviation is * SIGMAX, average life is AVGLIF, and the random sample size is N. * GEN1 MEANX=36000 GEN1 SIGMAX=4000 GEN1 AVGLIF=34500 GEN1 N=16 GEN1 SIGMAMX=SIGMAX/SQRT(N) PRINT SIGMAMX GEN1 PZ=(AVGLIF-MEANX)/SIGMAMX PRINT PZ * * From Table 3 of the Appendix, Fz(1.5)=0.9332 * GEN1 FZ=0.9332 GEN1 PMEANX=1-FZ PRINT PMEANX * DELETE / ALL * *---------------------------------------------------------------------------- * Example 6.4, page 235 * * The random sample of homes is defined as N and the proportion of homes with * unsafe wiring is P. * GEN1 N=250 GEN1 P=0.30 * * First calculate the standard error (SIGMAP). * GEN1 SIGMAP=SQRT((P*(1-P))/N) * * Then the probability that the proportion of homes in the sample with * unsafe wiring between 0.25 and 0.35 is: * GEN1 PL=(0.25-P)/SIGMAP GEN1 PU=(0.35-P)/SIGMAP PRINT PL PU * * From Table 3 of the Appendix, Fz(1.72)=0.9573 * GEN1 FZ=0.9573 GEN1 PX=FZ-(1-FZ) PRINT PX * DELETE / ALL * *---------------------------------------------------------------------------- * Example 6.5, page 236 * * The proportion of business graduates who believe a course in business ethics * is very important is P and the random sample size of business graduates is * N. * GEN1 P=0.43 GEN1 N=80 * * First calculate the standard error (SIGMAP). * GEN1 SIGMAP=SQRT((P*(1-P))/N) PRINT SIGMAP * * Then the probability that more than one-half of the business graduates * believe that a course in business ethics is very important is: * GEN1 P=(0.50-P)/SIGMAP PRINT P * * From Table 3 of the Appendix, Fz(1.27)=0.8980 * GEN1 FZ=0.8980 GEN1 PX=1-FZ PRINT PX * DELETE / ALL * *---------------------------------------------------------------------------- * Example 6.6, page 247 * * N is the random sample of components, SIGMAX is the standard deviation of * the components. * GEN1 N=4 GEN1 SIGMAX=3.6 GEN1 SIGMA2X=SIGMAX**2 * * The probability that the sample variance is greater than 30 is: * GEN1 PS2X=(30*(N-1))/SIGMA2X PRINT PS2X DELETE / ALL * *---------------------------------------------------------------------------- * Example 6.7, page 248 * * Read this example carefully. Be sure you understand the methodology. * *---------------------------------------------------------------------------- * STOP