Valuation of nature-based tourism using contingent valuation survey: evidence from South Africa

Figures & data

Figure 1. Kruger National Park. Source: https://www.safarinow.com/destinations/kruger-national-park/articles/kruger-national-park-map.aspx

Table 1. Responses to bids (n = 377).

Bid ($)	No	Yes	Total
20	0	75	75
	(0.0)	(100.0)	(100.0)
40	12	65	77
	(15.6)	(84.4)	(100.0)
60	25	51	76
	(32.9)	(67.1)	(100.0)
70	38	38	76
	(50.0)	(50.0)	(100.0)
90	40	33	73
	(54.8)	(45.2)	(100.0)
Total	115	262	377
	(30.5)	(69.5)	(100.0)

Note: The row percentage is given in parenthesis below the number of respondents.

Table 2. Descriptive statistics (n = 377).

Variable Description	Mean	SD	Min	Max
Number of recreation days on current trip (RDAYS)	3.35	3.17	1	27
Wildlife interest: between 1–5	0.15	0.35	0	1
Wildlife interest: interested	0.20	0.40	0	1
Wildlife interest: greatly interested	0.65	0.48	0	1
Reported tour satisfaction: between 1–5	0.25	0.44	0	1
Reported tour satisfaction: better than expected	0.37	0.48	0	1
Reported tour satisfaction: much better than expected	0.38	0.49	0	1
Package (1 if on tour package)	0.65	0.48	0	1
Gender (1 if male)	0.49	0.50	0	1
Age	40.23	15.53	16	81
Primary and high school	0.17	0.37	0	1
College certificate/diploma	0.18	0.39	0	1
Undergraduate degree	0.32	0.47	0	1
Postgraduate degree	0.33	0.47	0	1
Mid-point of household income brackets ($)	95,557	59,097	25,000	250,000

Table 3. Estimates of probit regression coefficients and mean and median willingness to pay (WTP) derived from the coefficients.

	Model 1	Marginal	Model 2	Marginal	Model 3	Marginal
		Effects		Effects		Effects
Intercept	7.275***		7.170***		4.397***
	(0.764)		(0.856)		(1.484)
Log(bid)	–1.675***	–0.510***	–1.768***	–0.522***	–1.858***	–0.540***
	(0.186)	(0.052)	(0.204)	(0.054)	(0.203)	(0.054)
Package (1 if on tour package)			0.358**	0.106**	0.346**	0.101**
			(0.160)	(0.047)	(0.163)	(0.047)
Satisfaction: better than expected			0.460**	0.136**	0.459**	0.133**
			(0.197)	(0.058)	(0.203)	(0.059)
Satisfaction: much better than expected			0.626***	0.185***	0.603***	0.175***
			(0.205)	(0.060)	(0.211)	(0.061)
Wildlife interest: interested			–0.275	–0.081	–0.313	–0.091
			(0.273)	(0.081)	(0.278)	(0.081)
Wildlife interest: greatly interested			–0.118	–0.035	–0.073	–0.021
			(0.226)	(0.067)	(0.235)	(0.068)
Age					–0.010*	–0.003*
					(0.006)	(0.002)
Gender (1 if male)					–0.171	–0.050
					(0.162)	(0.047)
Log income					0.338***	0.098***
					(0.122)	(0.035)
College certificate/diploma					–0.371	–0.108
					(0.282)	(0.082)
Undergraduate degree					–0.102	–0.030
					(0.253)	(0.074)
Postgraduate degree					–0.261	–0.076
					(0.249)	(0.073)
Mean WTP		91.843***		90.124***		87.943***
		(7.443)		(7.006)		(6.257)
Median WTP		76.858***		76.802***		76.081***
		(4.055)		(3.943)		(3.737)
AIC	377.0		371.6		371.2
BIC	384.9		399.1		422.3
Chi-squared	81.2		79.4		99.7
Log lik.	–186.5		–178.8		–172.6
Pseudo R^2	0.196		0.229		0.256
Observations	377		377		377

Note: For models using the logarithm of the bid as a covariate, the median WTP is given by $\mathrm{e}\mathrm{x}\mathrm{p}\left(-{\alpha }^{\mathrm{\prime }}\overline{Z}/{\mu }_1\right)$ and the mean WTP by $\mathrm{e}\mathrm{x}\mathrm{p}\left(-{\alpha }^{\mathrm{\prime }}\overline{Z}/{\mu }_1\right)\cdot \mathrm{e}\mathrm{x}\mathrm{p}\left({\displaystyle 1/[2\cdot {\mu }_1^2]}\right)$ where $\alpha$ is a vector of all regression coefficients excluding the bid, $\overline{Z}$ is a vector of sample means of the explanatory variables, and ${\mu }_1$ is the coefficient of the logarithm of the bid. The standard errors of the WTP estimates are calculated using the delta method and given in parentheses.

* p < 0.10, ** p < 0.05, *** p < 0.01.

Table 4. Estimated revenue effects.

Proposed fee ($)	$P\left[Yes\right]$	Number of tourists	Total revenue ($)	Additional revenue ($)
(p + t)			$\left(T{R}_t\right)$	$\left(T{R}_t-N\ast p\ast RDAYS\right)$
23	1	368,399	28,741,694	0
43	1	368,399	53,444,948	24,703,254
63	0.84	311,002	65,972,712	37,231,018
83	0.67	247,233	69,023,612	40,281,918
93	0.50	184,200	57,601,541	28,859,848
113	0.45	166,553	63,251,655	34,509,961

Table A1. Estimates of probit regression coefficients and mean willingness to pay (WTP) derived from the coefficients.

	Model 1	Marginal	Model 2	Marginal	Model 3	Marginal
		Effects		Effects		Effects
Intercept	2.302***		1.896***		–1.068
	(0.201)		(0.314)		(1.283)
Bid	–0.030***	–0.010***	–0.031***	–0.010***	–0.032***	–0.010***
	(0.003)	(0.001)	(0.003)	(0.001)	(0.003)	(0.001)
Package (1 if on tour package)			0.367**	0.116**	0.351**	0.110**
			(0.158)	(0.050)	(0.160)	(0.050)
Satisfaction: better than expected			0.447**	0.141**	0.446**	0.140**
			(0.193)	(0.061)	(0.197)	(0.062)
Satisfaction: much better than expected			0.616***	0.195***	0.592***	0.185***
			(0.201)	(0.063)	(0.206)	(0.064)
Wildlife interest: interested			–0.252	–0.080	–0.279	–0.087
			(0.269)	(0.085)	(0.270)	(0.085)
Wildlife interest: greatly interested			–0.115	–0.036	–0.065	–0.020
			(0.222)	(0.070)	(0.229)	(0.072)
Age					–0.009	–0.003
					(0.006)	(0.002)
Gender (1 if male)					–0.178	–0.056
					(0.159)	(0.050)
Log income					0.327***	0.102***
					(0.119)	(0.037)
College certificate/diploma					–0.305	–0.095
					(0.273)	(0.085)
Undergraduate degree					–0.093	–0.029
					(0.250)	(0.078)
Postgraduate degree					–0.256	–0.080
					(0.245)	(0.077)
Mean WTP		77.778***		77.762***		77.306***
		(3.128)		(3.062)		(2.935)
AIC	385.4		379.8		380.2
BIC	393.3		407.4		431.3
Chi-squared	88.6		90.0		109.1
Log lik.	–190.7		–182.9		–177.1
Pseudo R^2	0.178		0.211		0.236
Observations	377		377		377