1

************************************************************************************************************

************************************************************************************************************

National Survey Version_NR_Tests.docx

Author: Abt Associates Inc.

Created: 6/7/12

Updated: 7/5/12

Purpose: This file presents output from SAS code which compares characteristics of respondents to the National version of the

316(b) stated preference survey to survey non-respondents. Tests include the Student T-test, Mann-Whitney U Test (Wilcoxon Test),

and Chi-Squared Test of Proportions. Results were used in developing model weights.

************************************************************************************************************

************************************************************************************************************
2

**************************************************************************************************

National Survey Version - T-test for Age

**************************************************************************************************

The TTEST Procedure

Variable: age

sample N Mean Std Dev Std Err Minimum Maximum

main 275 54.1673 15.6977 0.9466 21.0000 89.0000

nonresponse 80 53.1625 18.7275 2.0938 19.0000 86.0000

Diff (1-2) 1.0048 16.4244 2.0864

sample Method Mean 95% CL Mean Std Dev 95% CL Std Dev

main 54.1673 52.3037 56.0308 15.6977 14.4862 17.1320

nonresponse 53.1625 48.9949 57.3301 18.7275 16.2078 22.1822

Diff (1-2) Pooled 1.0048 -3.0985 5.1081 16.4244 15.2971 17.7324

Diff (1-2) Satterthwaite 1.0048 -3.5476 5.5571

Method Variances DF t Value Pr > |t|

Pooled Equal 353 0.48 0.6304

Satterthwaite Unequal 113.23 0.44 0.6627

Equality of Variances

Method Num DF Den DF F Value Pr > F

Folded F 79 274 1.42 0.0408
3
4

**************************************************************************************************

National Survey Version – Mann Whitney U Test (Wilcoxon) for Gender

**************************************************************************************************

The NPAR1WAY Procedure

Wilcoxon Scores (Rank Sums) for Variable gender

Classified by Variable sample

sample N Sum of

Scores

Expected

Under H0

Std Dev

Under H0

Mean

Score

nonresponse 79 15773.0 14141.0 693.811906 199.658228

main 278 48130.0 49762.0 693.811906 173.129496

Average scores were used for ties.

Wilcoxon Two-Sample Test

Statistic 15773.0000

Normal Approximation

Z 2.3515

One-Sided Pr > Z 0.0093

Two-Sided Pr > |Z| 0.0187

t Approximation

One-Sided Pr > Z 0.0096

Two-Sided Pr > |Z| 0.0192

Z includes a continuity correction

of 0.5.

Kruskal-Wallis Test

Chi-Square 5.5330

DF 1

Pr > Chi-Square 0.0187
5
6

**************************************************************************************************

National Survey Version – Chi-Squared Test of Proportions for Gender

**************************************************************************************************

The FREQ Procedure

Frequency

Percent

Row Pct

Col Pct

Table of sample by gender

sample gender

male female Total

main 168

47.06

60.43

82.35

110

30.81

39.57

71.90

278

77.87

nonresponse 36

10.08

45.57

17.65

43

12.04

54.43

28.10

79

22.13

Total 204

57.14

153

42.86

357

100.00

Statistics for Table of sample by gender

Statistic DF Value Prob

Chi-Square 1 5.5485 0.0185

Likelihood Ratio Chi-Square 1 5.5004 0.0190

Continuity Adj. Chi-Square 1 4.9582 0.0260

Mantel-Haenszel Chi-Square 1 5.5330 0.0187

Phi Coefficient 0.1247

Contingency Coefficient 0.1237

Cramer's V 0.1247

Fisher's Exact Test

Cell (1,1) Frequency (F) 168

Left-sided Pr <= F 0.9933

Right-sided Pr >= F 0.0132

Table Probability (P) 0.0066

Two-sided Pr <= P 0.0207

Sample Size = 357
7

**************************************************************************************************

National Survey Version – Mann Whitney U Test (Wilcoxon) for Employment

**************************************************************************************************

The NPAR1WAY Procedure

Wilcoxon Scores (Rank Sums) for Variable employ

Classified by Variable sample

sample N Sum of

Scores

Expected

Under H0

Std Dev

Under H0

Mean

Score

nonresponse 79 14335.50 13983.0 679.461988 181.462025

main 274 48145.50 48498.0 679.461988 175.713504

Average scores were used for ties.

Wilcoxon Two-Sample Test

Statistic 14335.5000

Normal Approximation

Z 0.5181

One-Sided Pr > Z 0.3022

Two-Sided Pr > |Z| 0.6044

t Approximation

One-Sided Pr > Z 0.3024

Two-Sided Pr > |Z| 0.6047

Z includes a continuity correction

of 0.5.

Kruskal-Wallis Test

Chi-Square 0.2691

DF 1

Pr > Chi-Square 0.6039
8
9

**************************************************************************************************

National Survey Version – Chi-Squared Test of Proportions for Employment

**************************************************************************************************

The FREQ Procedure

Frequency

Percent

Row Pct

Col Pct

Table of sample by employ

sample employ

employed unemployed Total

main 165

46.74

60.22

78.57

109

30.88

39.78

76.22

274

77.62

nonresponse 45

12.75

56.96

21.43

34

9.63

43.04

23.78

79

22.38

Total 210

59.49

143

40.51

353

100.00

Statistics for Table of sample by employ

Statistic DF Value Prob

Chi-Square 1 0.2699 0.6034

Likelihood Ratio Chi-Square 1 0.2687 0.6042

Continuity Adj. Chi-Square 1 0.1517 0.6969

Mantel-Haenszel Chi-Square 1 0.2691 0.6039

Phi Coefficient 0.0277

Contingency Coefficient 0.0276

Cramer's V 0.0277

Fisher's Exact Test

Cell (1,1) Frequency (F) 165

Left-sided Pr <= F 0.7428

Right-sided Pr >= F 0.3471

Table Probability (P) 0.0899

Two-sided Pr <= P 0.6056

Sample Size = 353
10

**************************************************************************************************

National Survey Version – Mann Whitney U Test (Wilcoxon) for Hispanic/Latino

**************************************************************************************************

The NPAR1WAY Procedure

Wilcoxon Scores (Rank Sums) for Variable hisp

Classified by Variable sample

sample N Sum of

Scores

Expected

Under H0

Std Dev

Under H0

Mean

Score

nonresponse 79 13430.50 13904.0 372.575469 170.006329

main 272 48345.50 47872.0 372.575469 177.740809

Average scores were used for ties.

Wilcoxon Two-Sample Test

Statistic 13430.5000

Normal Approximation

Z -1.2695

One-Sided Pr < Z 0.1021

Two-Sided Pr > |Z| 0.2042

t Approximation

One-Sided Pr < Z 0.1025

Two-Sided Pr > |Z| 0.2051

Z includes a continuity correction

of 0.5.

Kruskal-Wallis Test

Chi-Square 1.6151

DF 1

Pr > Chi-Square 0.2038
11
12

**************************************************************************************************

National Survey Version – Chi-Squared Test of Proportions for Hispanic/Latino

**************************************************************************************************

The FREQ Procedure

Frequency

Percent

Row Pct

Col Pct

Table of sample by hisp

sample hisp

hispanic nothispanic Total

main 19

5.41

6.99

67.86

253

72.08

93.01

78.33

272

77.49

nonresponse 9

2.56

11.39

32.14

70

19.94

88.61

21.67

79

22.51

Total 28

7.98

323

92.02

351

100.00

Statistics for Table of sample by hisp

Statistic DF Value Prob

Chi-Square 1 1.6198 0.2031

Likelihood Ratio Chi-Square 1 1.4991 0.2208

Continuity Adj. Chi-Square 1 1.0750 0.2998

Mantel-Haenszel Chi-Square 1 1.6151 0.2038

Phi Coefficient -0.0679

Contingency Coefficient 0.0678

Cramer's V -0.0679

Fisher's Exact Test

Cell (1,1) Frequency (F) 19

Left-sided Pr <= F 0.1500

Right-sided Pr >= F 0.9298

Table Probability (P) 0.0797

Two-sided Pr <= P 0.2370

Sample Size = 351
13

**************************************************************************************************

National Survey Version – Mann Whitney U Test (Wilcoxon) for Education

**************************************************************************************************

The NPAR1WAY Procedure

Wilcoxon Scores (Rank Sums) for Variable education

Classified by Variable sample

sample N Sum of

Scores

Expected

Under H0

Std Dev

Under H0

Mean

Score

nonresponse 79 13663.50 14101.50 788.049809 172.955696

main 277 49882.50 49444.50 788.049809 180.081227

Average scores were used for ties.

Wilcoxon Two-Sample Test

Statistic 13663.5000

Normal Approximation

Z -0.5552

One-Sided Pr < Z 0.2894

Two-Sided Pr > |Z| 0.5788

t Approximation

One-Sided Pr < Z 0.2896

Two-Sided Pr > |Z| 0.5791

Z includes a continuity correction

of 0.5.

Kruskal-Wallis Test

Chi-Square 0.3089

DF 1

Pr > Chi-Square 0.5783
14
15

**************************************************************************************************

National Survey Version – Chi-Squared Test of Proportions for Education

**************************************************************************************************

The FREQ Procedure

Frequency

Percent

Row Pct

Col Pct

Table of sample by education

sample education

1 2 3 4 5 6 Total

main 13

3.65

4.69

72.22

47

13.20

16.97

78.33

26

7.30

9.39

76.47

61

17.13

22.02

73.49

85

23.88

30.69

84.16

45

12.64

16.25

75.00

277

77.81

nonresponse 5

1.40

6.33

27.78

13

3.65

16.46

21.67

8

2.25

10.13

23.53

22

6.18

27.85

26.51

16

4.49

20.25

15.84

15

4.21

18.99

25.00

79

22.19

Total 18

5.06

60

16.85

34

9.55

83

23.31

101

28.37

60

16.85

356

100.00

Statistics for Table of sample by education

Statistic DF Value Prob

Chi-Square 5 3.8976 0.5642

Likelihood Ratio Chi-Square 5 4.0266 0.5456

Mantel-Haenszel Chi-Square 1 0.2576 0.6118

Phi Coefficient 0.1046

Contingency Coefficient 0.1041

Cramer's V 0.1046

Sample Size = 356
16

**************************************************************************************************

National Survey Version – Mann Whitney U Test (Wilcoxon) for Importance of Aquatic Ecosystems

**************************************************************************************************

The NPAR1WAY Procedure

Wilcoxon Scores (Rank Sums) for Variable aquatic

Classified by Variable sample

sample N Sum of

Scores

Expected

Under H0

Std Dev

Under H0

Mean

Score

nonresponse 80 13877.50 14240.0 767.114431 173.468750

main 275 49312.50 48950.0 767.114431 179.318182

Average scores were used for ties.

Wilcoxon Two-Sample Test

Statistic 13877.5000

Normal Approximation

Z -0.4719

One-Sided Pr < Z 0.3185

Two-Sided Pr > |Z| 0.6370

t Approximation

One-Sided Pr < Z 0.3186

Two-Sided Pr > |Z| 0.6373

Z includes a continuity correction

of 0.5.

Kruskal-Wallis Test

Chi-Square 0.2233

DF 1

Pr > Chi-Square 0.6365
17
18

**************************************************************************************************

National Survey Version – Chi-Squared Test of Proportions for Importance of Aquatic Ecosystems

**************************************************************************************************

The FREQ Procedure

Frequency

Percent

Row Pct

Col Pct

Table of sample by aquatic

sample aquatic

1 2 3 4 5 Total

main 10

2.82

3.64

76.92

22

6.20

8.00

78.57

55

15.49

20.00

73.33

73

20.56

26.55

79.35

115

32.39

41.82

78.23

275

77.46

nonresponse 3

0.85

3.75

23.08

6

1.69

7.50

21.43

20

5.63

25.00

26.67

19

5.35

23.75

20.65

32

9.01

40.00

21.77

80

22.54

Total 13

3.66

28

7.89

75

21.13

92

25.92

147

41.41

355

100.00

Statistics for Table of sample by aquatic

Statistic DF Value Prob

Chi-Square 4 0.9915 0.9111

Likelihood Ratio Chi-Square 4 0.9672 0.9147

Mantel-Haenszel Chi-Square 1 0.1851 0.6670

Phi Coefficient 0.0528

Contingency Coefficient 0.0528

Cramer's V 0.0528

Sample Size = 355
19

**************************************************************************************************

National Survey Version – Mann Whitney U Test (Wilcoxon) for Income less than 60k

**************************************************************************************************

The NPAR1WAY Procedure

Wilcoxon Scores (Rank Sums) for Variable income_lt60k

Classified by Variable sample

Sum of Expected Std Dev Mean

sample N Scores Under H0 Under H0 Score

---------------------------------------------------------------------------

nonresponse 72 13257.0 11916.0 619.732750 184.125000

main 258 41358.0 42699.0 619.732750 160.302326

Average scores were used for ties.

Wilcoxon Two-Sample Test

Statistic 13257.0000

Normal Approximation

Z 2.1630

One-Sided Pr > Z 0.0153

Two-Sided Pr > |Z| 0.0305

t Approximation

One-Sided Pr > Z 0.0156

Two-Sided Pr > |Z| 0.0313

Z includes a continuity correction of 0.5.

Kruskal-Wallis Test

Chi-Square 4.6822

DF 1

Pr > Chi-Square 0.0305
20

**************************************************************************************************

National Survey Version – Chi-Squared Test of Proportions for Income less than 60k

**************************************************************************************************

The FREQ Procedure

Table of sample by income_lt60k

sample income_lt60k

Frequency |

Percent |

Row Pct |

Col Pct | 0| 1| Total

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

main | 134 | 124 | 258

| 40.61 | 37.58 | 78.18

| 51.94 | 48.06 |

| 83.23 | 73.37 |

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

nonresponse | 27 | 45 | 72

| 8.18 | 13.64 | 21.82

| 37.50 | 62.50 |

| 16.77 | 26.63 |

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

Total 161 169 330

48.79 51.21 100.00

Statistics for Table of sample by income_lt60k

Statistic DF Value Prob

------------------------------------------------------

Chi-Square 1 4.6964 0.0302

Likelihood Ratio Chi-Square 1 4.7418 0.0294

Continuity Adj. Chi-Square 1 4.1363 0.0420

Mantel-Haenszel Chi-Square 1 4.6822 0.0305

Phi Coefficient 0.1193

Contingency Coefficient 0.1185

Cramer's V 0.1193

Fisher's Exact Test

----------------------------------

Cell (1,1) Frequency (F) 134

Left-sided Pr <= F 0.9896

Right-sided Pr >= F 0.0207

Table Probability (P) 0.0102

Two-sided Pr <= P 0.0333

Sample Size = 330
21

**************************************************************************************************

National Survey Version – Mann Whitney U Test (Wilcoxon) for Race (minority)

**************************************************************************************************

The NPAR1WAY Procedure

Wilcoxon Scores (Rank Sums) for Variable race_minor

Classified by Variable sample

sample N Sum of

Scores

Expected

Under H0

Std Dev

Under H0

Mean

Score

nonresponse 73 12174.50 12373.50 501.654473 166.773973

main 265 45116.50 44917.50 501.654473 170.250943

Average scores were used for ties.

Wilcoxon Two-Sample Test

Statistic 12174.5000

Normal Approximation

Z -0.3957

One-Sided Pr < Z 0.3462

Two-Sided Pr > |Z| 0.6923

t Approximation

One-Sided Pr < Z 0.3463

Two-Sided Pr > |Z| 0.6926

Z includes a continuity correction

of 0.5.

Kruskal-Wallis Test

Chi-Square 0.1574

DF 1

Pr > Chi-Square 0.6916
22
23

**************************************************************************************************

National Survey Version – Chi-Squared Test of Proportions for Race (minority)

**************************************************************************************************

The FREQ Procedure

Frequency

Percent

Row Pct

Col Pct

Table of sample by race_minor

sample race_minor

minor white Total

main 49

14.50

18.49

76.56

216

63.91

81.51

78.83

265

78.40

nonresponse 15

4.44

20.55

23.44

58

17.16

79.45

21.17

73

21.60

Total 64

18.93

274

81.07

338

100.00

Statistics for Table of sample by race_minor

Statistic DF Value Prob

Chi-Square 1 0.1578 0.6912

Likelihood Ratio Chi-Square 1 0.1555 0.6934

Continuity Adj. Chi-Square 1 0.0523 0.8192

Mantel-Haenszel Chi-Square 1 0.1574 0.6916

Phi Coefficient -0.0216

Contingency Coefficient 0.0216

Cramer's V -0.0216

Fisher's Exact Test

Cell (1,1) Frequency (F) 49

Left-sided Pr <= F 0.4024

Right-sided Pr >= F 0.7187

Table Probability (P) 0.1211

Two-sided Pr <= P 0.7362

Sample Size = 338