Business Research Quiz

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Neal.LarryBUS457A7.docx

Question 1

Problem:

It is not certain about the relationship between age, Y, as a function of systolic blood pressure.

Goal:

To establish the relationship between age Y, as a function of systolic blood pressure.

Finding/Conclusion:

Based on the available data, the relationship is obtained and shown below:

Regression Analysis: Age versus SBP

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 1 2933 2933.1 21.33 0.000

SBP 1 2933 2933.1 21.33 0.000

Error 28 3850 137.5

Lack-of-Fit 21 2849 135.7 0.95 0.575

Pure Error 7 1002 143.1

Total 29 6783

Model Summary

S R-sq R-sq(adj) R-sq(pred)

11.7265 43.24% 41.21% 3.85%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant -18.3 13.9 -1.32 0.198

SBP 0.4454 0.0964 4.62 0.000 1.00

Regression Equation

Age = -18.3 + 0.4454 SBP

It is found that there is an outlier in the dataset, which significantly affect the regression equation. As a result, the outlier is removed, and the regression analysis is run again.

Regression Analysis: Age versus SBP

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 1 4828.5 4828.47 66.81 0.000

SBP 1 4828.5 4828.47 66.81 0.000

Error 27 1951.4 72.27

Lack-of-Fit 20 949.9 47.49 0.33 0.975

Pure Error 7 1001.5 143.07

Total 28 6779.9

Model Summary

S R-sq R-sq(adj) R-sq(pred)

8.50139 71.22% 70.15% 66.89%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant -59.9 12.9 -4.63 0.000

SBP 0.7502 0.0918 8.17 0.000 1.00

Regression Equation

Age = -59.9 + 0.7502 SBP

The p-value for the model is 0.000, which implies that the model is significant in the prediction of Age. The R-square of the model is 70.2%, implies that 70.2% of variation in age can be explained by the model

Recommendation:

The regression model Age = -59.9 +0.7502 SBP can be used to predict the Age, such that over 70% of variation in Age can be explained by the model.

Question 2

Problem:

It is not sure that whether the factors X1 to X4 which represents four different success factors have any influences on the annual savings as a result of CRM implementation.

Goal:

To determine which of the success factors are most significant in the prediction of a successful CRM program, and develop the corresponding model for the prediction of CRM savings.

Finding/Conclusion:

Based on the available data, the relationship is obtained and shown below:

Regression Analysis: Y versus X1, X2, X3, X4

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 4 2667.90 666.975 111.48 0.000

X1 1 25.95 25.951 4.34 0.071

X2 1 2.97 2.972 0.50 0.501

X3 1 0.11 0.109 0.02 0.896

X4 1 0.25 0.247 0.04 0.844

Error 8 47.86 5.983

Total 12 2715.76

Model Summary

S R-sq R-sq(adj) R-sq(pred)

2.44601 98.24% 97.36% 95.94%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant 62.4 70.1 0.89 0.399

X1 1.551 0.745 2.08 0.071 38.50

X2 0.510 0.724 0.70 0.501 254.42

X3 0.102 0.755 0.14 0.896 46.87

X4 -0.144 0.709 -0.20 0.844 282.51

Regression Equation

Y = 62.4 + 1.551 X1 + 0.510 X2 + 0.102 X3 - 0.144 X4

Correlation: Y, X2, X4

Y X2

X2 0.816

0.001

X4 -0.821 -0.973

0.001 0.000

Based on the analysis of VIF and the correlations, it can be seen that there is a strong negative correlation between X2 and X4. Since X4 has a stronger correlation with Y, X2 is discarded and the regression analysis is run again.

Regression Analysis: Y versus X1, X3, X4

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 3 2664.93 888.31 157.27 0.000

X1 1 124.90 124.90 22.11 0.001

X3 1 23.93 23.93 4.24 0.070

X4 1 1176.24 1176.24 208.24 0.000

Error 9 50.84 5.65

Total 12 2715.76

Model Summary

S R-sq R-sq(adj) R-sq(pred)

2.37665 98.13% 97.50% 96.52%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant 111.68 4.56 24.48 0.000

X1 1.052 0.224 4.70 0.001 3.68

X3 -0.410 0.199 -2.06 0.070 3.46

X4 -0.6428 0.0445 -14.43 0.000 1.18

Regression Equation

Y = 111.68 + 1.052 X1 - 0.410 X3 - 0.6428 X4

The p-value of X3 is greater than 0.05. As a result it is also discarded. The analysis is run again.

Regression Analysis: Y versus X1, X4

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 2 2641.00 1320.50 176.63 0.000

X1 1 809.10 809.10 108.22 0.000

X4 1 1190.92 1190.92 159.30 0.000

Error 10 74.76 7.48

Total 12 2715.76

Model Summary

S R-sq R-sq(adj) R-sq(pred)

2.73427 97.25% 96.70% 95.54%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant 103.10 2.12 48.54 0.000

X1 1.440 0.138 10.40 0.000 1.06

X4 -0.6140 0.0486 -12.62 0.000 1.06

Regression Equation

Y = 103.10 + 1.440 X1 - 0.6140 X4

Both of the coefficients for X1 and X4 are significantly different from zero, with p-value being 0.000 for both of the coefficients. The p-value of overall model is also 0.000, and thus it is significant in predicting the CRM savings. The R-square of the model is 97.25%, which implies that 97.25% of the variation in CRM savings can be explained by the model.

The prediction model is given by: 103.10 + 1.440X1 -0.6140X4

Recommendation:

Since both X1 and X4 are both strongly correlated to the CRM savings, it is essential to ensure that both X1 and X4 are present in the implementation of CRM system.

The prediction model obtained can be used in estimating the CRM savings, given that no other success factors are being incorporated, and the data used for estimation are within the ranges of the analysis here.

Question 3

Problem:

It is not sure whether any of the case load, DRG type, case severity and patient follow-up time are significant in influencing the high readmission rates, where readmissions are very expensive and produce tremendous hardship for patients.

Goal:

To determine which of the factors of case load, DRG type, case severity and patient follow-up time are significant in the prediction of readmission rates, and develop the corresponding measure to reduce the readmission rates.

Finding/Conclusion:

Based on the available data, the relationship is obtained and shown below:

From the matrix plot, it can be seen that there is a quadratic relationship between the Readmission rate and the Time. As a result, a quadratic term of Time will be included in the regression model.

Regression Analysis: ReadmitRate versus Census, Severity, Time, DRG

Method

Categorical predictor coding (1, 0)

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 6 0.013839 0.002306 63.72 0.000

Census 1 0.000115 0.000115 3.18 0.088

Severity 1 0.000095 0.000095 2.61 0.120

Time 1 0.005527 0.005527 152.69 0.000

DRG 2 0.000032 0.000016 0.44 0.649

Time*Time 1 0.005740 0.005740 158.57 0.000

Error 22 0.000796 0.000036

Total 28 0.014635

Model Summary

S R-sq R-sq(adj) R-sq(pred)

0.0060165 94.56% 93.07% 90.34%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant -1.0356 0.0840 -12.33 0.000

Census 0.000039 0.000022 1.78 0.088 2.39

Severity -0.001489 0.000921 -1.62 0.120 2.81

Time 0.1661 0.0134 12.36 0.000 526.86

DRG

B 0.00274 0.00294 0.93 0.361 1.57

C 0.00158 0.00297 0.53 0.600 1.41

Time*Time -0.006244 0.000496 -12.59 0.000 522.14

Regression Equation

DRG

A ReadmitRate = -1.0356 + 0.000039 Census - 0.001489 Severity + 0.1661 Time

- 0.006244 Time*Time

B ReadmitRate = -1.0329 + 0.000039 Census - 0.001489 Severity + 0.1661 Time

- 0.006244 Time*Time

C ReadmitRate = -1.0341 + 0.000039 Census - 0.001489 Severity + 0.1661 Time

- 0.006244 Time*Time

All the coefficients except Time are not significantly different from zero, with p-values of all the coefficient greater than 0.05. As a result, all of these variables will be discarded.

Regression Analysis: ReadmitRate versus Time

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 2 0.013627 0.006814 175.76 0.000

Time 1 0.011221 0.011221 289.43 0.000

Time*Time 1 0.011825 0.011825 305.03 0.000

Error 26 0.001008 0.000039

Lack-of-Fit 22 0.000975 0.000044 5.37 0.057

Pure Error 4 0.000033 0.000008

Total 28 0.014635

Model Summary

S R-sq R-sq(adj) R-sq(pred)

0.0062264 93.11% 92.58% 90.75%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant -1.0088 0.0654 -15.43 0.000

Time 0.16763 0.00985 17.01 0.000 264.25

Time*Time -0.006375 0.000365 -17.47 0.000 264.25

Regression Equation

ReadmitRate = -1.0088 + 0.16763 Time - 0.006375 Time*Time

All the regression coefficients in the final model is significantly different from zero, with p-value of both coefficient of Time and Time^2 being 0.000. The p-value of the overall model is also 0.000, which implies that the model is significant in predicting the readmission rate. The residual plots do not indicate any significant deviation from the assumption of linear models. The R-square of the model is 93.11%, which implies that 93.11% of variation in the readmission rate can be explained by the model.

Prediction for ReadmitRate

Regression Equation

ReadmitRate = -1.0088 + 0.16763 Time - 0.006375 Time*Time

Variable Setting

Time 13.1

Fit SE Fit 95% CI 95% PI

0.0929927 0.0017406 (0.0894149, 0.0965704) (0.0797035, 0.106282)

The median value for Time is 13.1 days. At this value, the readmission rate is estimated to be about 9.3%

The range within which we can expect the average patient readmission rate to fall with 95% confidence is between 8.9% and 9.6%

The rate within which we can expect an individual patient’s readmission rate to fall with 95% confidence is between 7.9% and 10.6%

Recommendation:

The regression model found is Readmission rate = -1.0088 + 0.16763 Time -0.006375 Time2

This model can explain more than 93% of variation in readmission rate, and simply using patient follow-up time to predict the readmission rate. It is recommended to use the model for the range of data within those being used in the analysis.

Question 4

Problem:

It is not sure whether any of the given predictors can be used to estimate the gas mileage

Goal:

To determine the best model using the predictor variables that can estimate the gas mileage.

Finding/Conclusion:

First of all, there are two observations with missing values and they are being removed.

Based on different trial of combinations of predictors, the final best model is shown below:

Regression Analysis: Y versus X1

Analysis of Variance

Source DF Adj SS Adj MS F-Value P-Value

Regression 2 934.00 466.998 61.47 0.000

X1 1 209.46 209.461 27.57 0.000

X1*X1 1 67.77 67.768 8.92 0.006

Error 27 205.11 7.597

Lack-of-Fit 16 142.13 8.883 1.55 0.232

Pure Error 11 62.98 5.725

Total 29 1139.11

Model Summary

S R-sq R-sq(adj) R-sq(pred)

2.75621 81.99% 80.66% 77.59%

Coefficients

Term Coef SE Coef T-Value P-Value VIF

Constant 39.98 2.56 15.61 0.000

X1 -0.1059 0.0202 -5.25 0.000 20.89

X1*X1 0.000109 0.000036 2.99 0.006 20.89

Regression Equation

Y = 39.98 - 0.1059 X1 + 0.000109 X1*X1

It is found that the best model only used X1 as the predictor variable. Both X1 and X12 have p-value of 0.000 for the estimated coefficient. The R-square of the model is 81.99%, which implies that 81.99% of variation in the gas mileage can be explained by the model. The best model is given by Gas mileage = 39.98 – 0.1059X1 + 0.000109 X12.

Recommendation:

The model using only X1 as the predictor variable is recommended. This is due to its simplicity while at the same time can explain more than 80% of variation of gas mileage.

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Neal.LarryBUS457A6.docx

Larry Neal

Assignment 6

BUS 457

11/09/2014

Question 1

Problems:

It is not sure whether meeting the daily patient discharge target is dependent upon the number of consulting MD’s available.

Goals:

To determine whether dependency exists between discharge target and number of consulting MD’s, and make adjustment for a balanced approach to staffing for discharge purposes.

Findings / Conclusion:

Chi-square test is being used in the analysis. The result of the analysis is shown below:

Rows: Met_Discharges Columns: Consulting MDs

0 1 2 3 All

No 95 148 95 54 392

92.75 152.80 91.29 55.16

Yes 95 165 92 59 411

97.25 160.20 95.71 57.84

All 190 313 187 113 803

Cell Contents: Count

Expected count

Pearson Chi-Square = 0.744, DF = 3, P-Value = 0.863

Likelihood Ratio Chi-Square = 0.744, DF = 3, P-Value = 0.863

From the result of the chi-square test, the p-value of the chi-square test is 0.863. Since the p-value is greater than 0.05, the null hypothesis cannot be rejected and there is not sufficient evidence to conclude that dependency exists between discharge target and number of consulting MD’s

Recommendation:

Other factors instead of number of consulting MD’s should be investigated to improve meeting patient discharge targets.

Question 2a

Problems:

It is not sure whether annual sales volume is dependent upon sales proposal being won or lost over 2 years period.

Goals:

To determine whether dependency exists between annual sales volume and sales proposal being won or lost.

Findings / Conclusion:

Chi-square test is being used in the analysis. The result of the analysis is shown below:

Rows: Proposal Columns: Sales$

<1M >5M 1-2M 2-5M All

Lost 25 30 31 41 127

20.95 29.21 29.21 47.63

Won 8 16 15 34 73

12.05 16.79 16.79 27.38

All 33 46 46 75 200

Cell Contents: Count

Expected count

Pearson Chi-Square = 5.023, DF = 3, P-Value = 0.170

Likelihood Ratio Chi-Square = 5.097, DF = 3, P-Value = 0.165

From the result of the chi-square test, the p-value of the chi-square test is 0.170. Since the p-value is greater than 0.05, the null hypothesis cannot be rejected and there is not sufficient evidence to conclude that dependency exists between annual sales volume and sales proposal being won or lost.

Recommendation:

Other factors instead of sales volume or in addition to volume should be investigated to identify factors that can increase the number of sales proposals won.

Question 2b

Problems:

It is not sure whether annual sales volume conditional on seniority and company car is dependent upon sales proposal being won or lost over 2 years period.

Goals:

To determine whether dependency exists between annual sales volume and sales proposal being won or lost, conditional on seniority and company car.

Findings / Conclusion:

Chi-square test is being used in the analysis. The result of the analysis conditional on seniority is shown below:

Tabulated Statistics: Proposal, Sales$, Seniority

Results for Seniority = <5years

Rows: Proposal Columns: Sales$

<1M >5M 1-2M 2-5M All

Lost 13 11 16 22 62

8.857 13.918 13.918 25.306

1.9378 0.6119 0.3113 0.4319

Won 1 11 6 18 36

5.143 8.082 8.082 14.694

3.3373 1.0539 0.5362 0.7439

All 14 22 22 40 98

Cell Contents: Count

Expected count

Contribution to Chi-square

Pearson Chi-Square = 8.964, DF = 3, P-Value = 0.030

Likelihood Ratio Chi-Square = 10.339, DF = 3, P-Value = 0.016

Results for Seniority = 5+years

Rows: Proposal Columns: Sales$

<1M >5M 1-2M 2-5M All

Lost 12 19 15 19 65

12.11 15.29 15.29 22.30

0.00096 0.89796 0.00566 0.48942

Won 7 5 9 16 37

6.89 8.71 8.71 12.70

0.00169 1.57750 0.00994 0.85978

All 19 24 24 35 102

Cell Contents: Count

Expected count

Contribution to Chi-square

Pearson Chi-Square = 3.843, DF = 3, P-Value = 0.279

Likelihood Ratio Chi-Square = 4.027, DF = 3, P-Value = 0.259

From the result of the chi-square test conditional on the layer of seniority, it can be seen that for the layer with seniority less than or equal to 5 years, the p-value of the chi-square test is 0.030. Since the p-value is smaller than 0.05, the null hypothesis is rejected and there is sufficient evidence to conclude that dependency exists between annual sales volume and sales proposal being won or lost for those with seniority less than or equal to 5 years.

The result of the analysis conditional on seniority is shown below:

Tabulated Statistics: Proposal, Sales$, CompanyCar

Results for CompanyCar = No

Rows: Proposal Columns: Sales$

<1M >5M 1-2M 2-5M All

Lost 12 17 11 24 64

9.06 16.91 11.47 26.57

0.95660 0.00053 0.01940 0.24786

Won 3 11 8 20 42

5.94 11.09 7.53 17.43

1.45768 0.00080 0.02956 0.37769

All 15 28 19 44 106

Cell Contents: Count

Expected count

Contribution to Chi-square

Pearson Chi-Square = 3.090, DF = 3, P-Value = 0.378

Likelihood Ratio Chi-Square = 3.318, DF = 3, P-Value = 0.345

Results for CompanyCar = Yes

Rows: Proposal Columns: Sales$

<1M >5M 1-2M 2-5M All

Lost 13 13 20 17 63

12.06 12.06 18.10 20.78

0.0726 0.0726 0.2004 0.6865

Won 5 5 7 14 31

5.94 5.94 8.90 10.22

0.1476 0.1476 0.4072 1.3951

All 18 18 27 31 94

Cell Contents: Count

Expected count

Contribution to Chi-square

Pearson Chi-Square = 3.130, DF = 3, P-Value = 0.372

Likelihood Ratio Chi-Square = 3.069, DF = 3, P-Value = 0.381

From the result of the Chi-square test, it can be seen that the p-values for not having company car and having company car are 0.378 and 0.372 respectively. Therefore it can be conclude that regardless of having company car, the sales volume and proposal win or loss numbers are not significantly dependent.

Recommendations:

Lower seniority salespersons are more adept at winning the proposals with less than one million dollars than higher seniority salespersons. Therefore low seniority staff should be assigned to lower payoff clients initially. Company car will not be a valid motivation factor in sales and thus should not be used.

Question 3a

Problems:

It is not sure whether authorization errors for medical services are dependent upon department.

Goals:

To determine whether dependency exists between authorization errors for medical services and department.

Findings / Conclusion:

Chi-square test is being used in the analysis. The result of the analysis is shown below:

Rows: defect Columns: dep cd

DEP EE SP All

No 16 55 12 83

17.15 52.57 13.28

0.0775 0.1126 0.1234

Yes 15 40 12 67

13.85 42.43 10.72

0.0961 0.1395 0.1528

All 31 95 24 150

Cell Contents: Count

Expected count

Contribution to Chi-square

Pearson Chi-Square = 0.702, DF = 2, P-Value = 0.704

Likelihood Ratio Chi-Square = 0.701, DF = 2, P-Value = 0.704

From the result of the Chi-square test, it can be seen that the p-value is 0.704. Since the p-value is greater than 0.05, the null hypothesis cannot be rejected. Therefore there is not sufficient evidence to conclude that dependency exists between authorization errors for medical services and department.

Recommendations:

Department is not a significant factor in influencing authorization errors, and thus other factors should be explored.

Question 3b

Problems:

It is not sure whether authorization errors for medical services are dependent upon case entry site.

Goals:

To determine whether dependency exists between authorization errors for medical services and case entry site.

Findings / Conclusion:

Chi-square test is being used in the analysis. The result of the analysis is shown below:

Rows: defect Columns: Case Enter Site

HOU PDX PHL SD SFO All

No 11 17 26 7 22 83

10.51 18.26 26.56 6.09 21.58

0.02253 0.08694 0.01181 0.13705 0.00817

Yes 8 16 22 4 17 67

8.49 14.74 21.44 4.91 17.42

0.02791 0.10771 0.01463 0.16978 0.01013

All 19 33 48 11 39 150

Cell Contents: Count

Expected count

Contribution to Chi-square

Pearson Chi-Square = 0.597, DF = 4, P-Value = 0.963

Likelihood Ratio Chi-Square = 0.601, DF = 4, P-Value = 0.963

* NOTE * 1 cells with expected counts less than 5

From the result of the Chi-square test, it can be seen that the p-value is 0.963. Since the p-value is greater than 0.05, the null hypothesis cannot be rejected. Therefore there is not sufficient evidence to conclude that dependency exists between authorization errors for medical services and case entry site.

Recommendations:

Case entry site is not a significant factors in influencing authorization errors, and thus other factors should be explored. However, it should be noted that the expected cell count for San Diego (SD) logging a “Yes” response is less than 5, it is recommended that more data to be collected with the response for San Diego (SD) logging being “Yes” such that the count of data is greater than 5. The test is suggested to be redone at that time.

Neal.LarryBUS457A5.docx

Larry Neal

Assignment 5

BUS 457

10/31/2014

Q1.

Problem:

For a supply chain project team it is not certain whether international orders placed on weekends is longer than that of those placed on a weekday, which is 3 days. The team will pursue weekend shipment time improvements only if it is proven that the median weekend order shipments are significantly longer than 4 days.

Goal:

Determine whether the median weekend order shipments are significantly longer than 4 days.

Findings / Conclusions:

A Wilcoxon signed rank test is carried out to test for the median. The result is shown below:

Wilcoxon Signed Rank Test: ShipTime

Test of median = 4.000 versus median > 4.000

N for Wilcoxon Estimated

N Test Statistic P Median

ShipTime 37 30 351.0 0.008 6.500

From the result, it can be seen that the p-value of the test is 0.008. Therefore the null hypothesis is rejected at 5% significant level. There is sufficient statistical evidence to infer the median ship time for weekend international order is significantly longer than 4.0 days.

Recommendation:

Pursue weekend international orders improvements as a means, in part, to bring weekend shipments more in line with the week day shipment median of 3.0 days.

Q2

Problem:

Verify the theory that the patient length of stay is generally longer when they miss the target of patient discharge than when they don’t.

Goal:

Determine whether the length of stay is longer when they miss the patient discharge target than when they don’t.

Findings / Conclusion:

A Mann-Whitney test is carried out to test for the hypothesis of median length of stay whether missing the patient discharge target is longer than when not. The result of the test is shown below:

Mann-Whitney Test and CI: LOS_No, LOS_Yes

N Median

LOS_No 392 2.0000

LOS_Yes 411 2.0000

Point estimate for η1 - η2 is -0.0000

95.0 Percent CI for η1 - η2 is (-0.0001,0.0001)

W = 158801.0

Test of η1 = η2 vs η1 > η2 is significant at 0.3556

The test is significant at 0.3523 (adjusted for ties)

Based on the result of the test, the p-value is 0.3523. Therefore the null hypothesis is not rejected. There is not sufficient evidence to conclude that the median length of stay when they miss the target is longer than when they don’t.

Recommendation:

Whether meeting the patient discharge targets has no influence on the patient length of stay, and thus other factors should be considered when it is intended to adjust for length of stay.

Q3

Problem:

It is uncertain that which of the factors among hospitalist group, number of consulting MDs and payer have significant influence on the excessive patient length of stay at Basin Medical Center.

Goal:

Determine which, if any of the factors of hospitalist group, number of consulting MDs and payer have significant influence on excessive patient length of stay.

Findings / Conclusion:

Since the research data are subject to outliers and are not normally distributed, Mood’s Median nonparametric test was used to carry out the hypothesis test. The result of test between length of stay and hospitalist groups is shown below:

Mood Median Test: LOS versus Hospitalist Group

Mood median test for LOS

Chi-Square = 4.30 DF = 2 P = 0.116

Hospitalist Individual 95.0% CIs

Group N≤ N> Median Q3-Q1 ---+---------+---------+---------+---

Galen 129 150 3.00 3.00 (--------------------------------*

n/a 243 211 2.00 1.00 *--------------------------------)

Pediatrix 39 31 2.00 1.00 *--------------------------------)

---+---------+---------+---------+---

2.10 2.40 2.70 3.00

Overall median = 2.00

Based on the result of the test, it is found that the p-value of the test is 0.116. Therefore the null hypothesis is not rejected, and there are not sufficient evidence to conclude that median length of stay is different among hospitalist groups.

The result of the test between the length of stay and number of consulting MDs is shown below:

Mood Median Test: LOS versus Number of Consulting MDs

Mood median test for LOS

Chi-Square = 88.39 DF = 3 P = 0.000

Number of

Consulting Individual 95.0% CIs

MDs N≤ N> Median Q3-Q1 ---+---------+---------+---------+---

0 133 57 2.00 1.25 *

1 175 138 2.00 2.00 *

2 85 102 3.00 2.00 (-------*

3 18 95 5.00 6.00 (--------*-------)

---+---------+---------+---------+---

2.4 3.6 4.8 6.0

Overall median = 2.00

Based on the result of the test, it is found that the p-value of the test is 0.000. Therefore the null hypothesis is rejected, and there are sufficient evidence to conclude that median length of stay is different among consulting MDs with three consulting MDs produced a median length of stay of 5 days.

The result of the test between the length of stay and payer is shown below:

Mood Median Test: LOS versus Payer

Mood median test for LOS

Chi-Square = 51.31 DF = 6 P = 0.000

Payer N≤ N> Median Q3-Q1

Commercial 135 108 2.00 2.00

County 50 36 2.00 1.00

MediCal 76 61 2.00 1.00

Medicare 90 162 3.00 3.00

Other General Ins 18 0 1.00 1.00

Self Pay 33 23 2.00 3.00

Sutter Select 9 2 2.00 1.00

Individual 95.0% CIs

Payer +---------+---------+---------+------

Commercial *---------)

County *---------)

MediCal *---------)

Medicare *---------)

Other General Ins *---------)

Self Pay *---------)

Sutter Select (---------*)

+---------+---------+---------+------

1.0 2.0 3.0 4.0

Overall median = 2.00

Based on the result of the test, it is found that the p-value of the test is 0.000. Therefore the null hypothesis is rejected, and there are sufficient evidence to conclude that median length of stay is different among payer type with payer type of Medicare produced a median length of stay of 3 days.

Recommendations:

In order to solve the problem of excessive length of stay, the number of consulting MDs should be limited to two at most, and means in reducing excessive length of stay should focus on those who receive Medicre benefits.

4.

Problem:

It is interested to know whether different types of Enterprise Resource Planning software influence the purchasing decision for the customer, and a survey is carried out to ask for the customers’ opinion on it.

Goal:

Determine whether features in ERP software has influence on customer purchase decisions. If so, identify which type of ERP software is most influential.

Findings / Conclusion:

Since the data are not subject to outliers and the data are not normally distributed, a Kruskal-Wallis nonparametric test is selected for the research analysis.

The result of the test is shown below:

Kruskal-Wallis Test: Response versus ERPtype

Kruskal-Wallis Test on Response

ERPtype N Median Ave Rank Z

A 1 3.000 9.5 -0.25

B 8 2.500 8.2 -1.63

C 2 2.000 5.0 -1.44

D 9 8.000 15.7 2.98

E 1 2.000 5.0 -0.99

Overall 21 11.0

H = 9.60 DF = 4 P = 0.048

H = 10.03 DF = 4 P = 0.040 (adjusted for ties)

* NOTE * One or more small samples

Based on the result of the test, the p-value is 0.040. The null hypothesis is rejected at 5% significant level. There is sufficient evidence to conclude that there is significant differences in median response on the survey question of the opinion on whether the ERP software features influence the purchase decision. From the median, it can be seen that ERP type D has the largest median response to this question.

Recommendation:

Since the ERP type D has the largest satisfaction, the marketing strategy should be on promoting the feature of ERP type D software. More resources should be placed in further development on the features of ERP type D, and less resources should be put on other ERP types of software.