***************************************************************************** * CHAPTER 7 - STATISTICS FOR BUSINESS & ECONOMICS, 5th Edition * ***************************************************************************** * Example 7.1, p. 222 * * 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 cae, 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 7.2, p. 224 * * 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 1 of the Appendix, Fz(1.83)=0.9664 * GEN1 FZ=0.9664 GEN1 PMEANX=1-FZ PRINT PMEANX * * The above probability PMEANX can be easily calculated in SHAZAM with the * the GEN1 and DISTRIB command is used to print out critical values in lieu * of referring to a statistical table. The GEN1 command is used to generate * a constant, X, at the 1% level of significance before the DISTRIB command * can be executed. The format of the DISTRIB command is: * * DISTRIB vars / options * * where: vars = list of variables * options = list of desired options * TYPE= - specifies the type of distribution * DF= - specifies the degrees of freedom * INVERSE = computes the inverse survival function * GEN1 Z=12.2 GEN1 SIG2=1.2**2 DISTRIB Z / TYPE=NORMAL MEAN=10 VAR=SIG2 * DELETE / ALL *---------------------------------------------------------------------------- * Example 7.3, p. 225 * * 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 * GEN1 Z=36000 GEN1 SIG2=1000**2 DISTRIB Z / TYPE=NORMAL MEAN=34500 VAR=SIG2 * DELETE / ALL *---------------------------------------------------------------------------- * Example 7.4, 231 * * The Per Capita Annual Income and its standard deviation is defined as MEAN * and SIGMA. The random sample and mean income is defined as N and XBAR. * GEN1 MEAN=60000 GEN1 SIGMA=5000 GEN1 N=36 GEN1 XBAR=62300 GEN1 Z=(XBAR-MEAN)/(SIGMA/SQRT(N)) PRINT Z * GEN1 P=60000 GEN1 SIG2=(5000/SQRT(36))**2 DISTRIB P / TYPE=NORMAL MEAN=62300 VAR=SIG2 * DELETE / ALL *---------------------------------------------------------------------------- * Example 7.5, 231 * * The mean for the random sample claims, mean level for individual claims, * standard deviation is defined as N, MEAN and SIGMA. The 95 percent * confidence interval for the insurance claim is defined as UPPER for the * upper bound and LOWER for the lower bound. * GEN1 N=100 GEN1 MEAN=4000 GEN1 SIGMA=2000 GEN1 Z95=1.96 GEN1 UPPER=MEAN+Z95*(SIGMA/(SQRT(N))) GEN1 LOWER=MEAN-Z95*(SIGMA/(SQRT(N))) PRINT UPPER LOWER * DELETE / ALL *---------------------------------------------------------------------------- * Example 7.6, p. * * Read this example carefully. Be sure you understand the methodology. * *---------------------------------------------------------------------------- * Example 7.7, p.237 * * The random sample of homes is defined as N and the proportion of homes with * unsafe wiring is M. * GEN1 N=250 GEN1 M=0.30 * * First calculate the standard error (SIGMAP). * GEN1 SIGMAP=SQRT((M*(1-M))/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-M)/SIGMAP GEN1 PU=(0.35-M)/SIGMAP PRINT PL PU * GEN1 Z=0.30 GEN1 VAR=0.029**2 DISTRIB Z / TYPE=NORMAL MEAN=0.25 VAR=VAR GEN1 CDF=$CDF DISTRIB Z / TYPE=NORMAL MEAN=0.35 VAR=VAR GEN1 VALUE=CDF-$CDF PRINT VALUE * DELETE / ALL *---------------------------------------------------------------------------- * Example 7.8, p. 238 * * The proportion of business graduates who believe a course in business ethics * is very important is M and the random sample size of business graduates is * N. * GEN1 M=0.43 GEN1 N=80 * * First calculate the standard error (SIGMAP). * GEN1 SIGMAP=SQRT((M*(1-M))/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 M=(0.50-M)/SIGMAP PRINT M * GEN1 Z=0.43 GEN1 VAR=0.055**2 DISTRIB Z / TYPE=NORMAL MEAN=0.50 VAR=VAR * DELETE / ALL *---------------------------------------------------------------------------- * Example 7.9, p. 244 * * N is the random sample of components, SIGMAX is the standard deviation of * the components. * GEN1 N=6 GEN1 SIGMA=3.6 GEN1 SIGMA2=SIGMA**2 * * Upper Limit, K is: * GEN1 K=(11.07*SIGMA2)/(N-1) PRINT K * GEN1 X=0.05 DISTRIB X / TYPE=CHI DF=5 INVERSE * DELETE / ALL *---------------------------------------------------------------------------- * Example 7.10, p. 244 * * Read this example carefully. Be sure you understand the methodology. * *---------------------------------------------------------------------------- * STOP