The Magnitude of Hypothetical BiasT

The Magnitude of Hypothetical Bias

The extent to which WTP for new products, and the marginal WTP for nutrition information, can be accurately assessed in a hypothetical setting can be seen by comparing the magnitudes of WTP in treatments 2 and 3, as shown in Table 4. It is evident that in the absence of a cheap talk script, hypothetical bias is large: on average, participants overstated their WTP by a factor of above 2 in hypothetical scenarios compared to real scenarios. This supports the findings reported in List and Gallet (2001). In addition, the marginal WTP estimates from the hypothetical choices are also overstated. As might be expected, the degree of hypothetical bias for white varieties is minimal, since this is the product with which consumers are familiar. Note that unlike the case in most hypothetical elicitation experiments, consumers in Uganda had an opportunity to taste the three products that they were being asked to assess. So the difference in the “real” and “hypothetical” arms cannot be attributed to their experience
with the product, but entirely to the fact that in the real treatment respondents had to make
a purchase, whereas in the hypothetical arm, they did not have to do so.

The Mitigation of Hypothetical Bias through Cheap Talk
Turning to the effectiveness of cheap talk in mitigating hypothetical bias, the results
suggest that although the use of a cheap talk script does result in a reduction in the
magnitude of the willingness to pay, the bias remains substantial. This finding is of
interest because, unlike most other cheap talk scripts, such as those used by Cummings
and Taylor (1999) and List (2001) which explicitly indicate the direction of bias, the cheap
talk script used in this study was deliberately neutral in its wording. Nonetheless, the
cheap talk had the desired effect of lowering hypothetical bias, but it did not eliminate it.
For example, the WTP for deep orange in the hypothetical arm was UGS750 per kilogram, more than double the UGS357 in the real arm, whereas with cheap talk the WTP estimates drop to UGS553/kilogram; hence considerably lower than 750UGS/kilogram, but still much higher than the UGS357/kilogram. Upward biases are also seen in the estimated marginal willingness to pay for orange and deep orange varieties as well, although once again these biases are lower than was the case in the hypothetical scenario without using a cheap talk script.

Kết quả (Việt) 1:

The Magnitude of Hypothetical BiasThe extent to which WTP for new products, and the marginal WTP for nutrition information, can be accurately assessed in a hypothetical setting can be seen by comparing the magnitudes of WTP in treatments 2 and 3, as shown in Table 4. It is evident that in the absence of a cheap talk script, hypothetical bias is large: on average, participants overstated their WTP by a factor of above 2 in hypothetical scenarios compared to real scenarios. This supports the findings reported in List and Gallet (2001). In addition, the marginal WTP estimates from the hypothetical choices are also overstated. As might be expected, the degree of hypothetical bias for white varieties is minimal, since this is the product with which consumers are familiar. Note that unlike the case in most hypothetical elicitation experiments, consumers in Uganda had an opportunity to taste the three products that they were being asked to assess. So the difference in the “real” and “hypothetical” arms cannot be attributed to their experience with the product, but entirely to the fact that in the real treatment respondents had to make a purchase, whereas in the hypothetical arm, they did not have to do so.The Mitigation of Hypothetical Bias through Cheap TalkTurning to the effectiveness of cheap talk in mitigating hypothetical bias, the results suggest that although the use of a cheap talk script does result in a reduction in the tầm quan trọng của sự sẵn lòng để trả tiền, các thiên vị vẫn còn đáng kể. Tìm kiếm này là của quan tâm bởi vì, không giống như hầu hết các giá rẻ nói kịch bản, chẳng hạn như những người sử dụng bởi Cummings và Taylor (1999) và danh sách (2001) một cách rõ ràng chỉ ra sự chỉ đạo của thiên vị, giá rẻ nói chuyện kịch bản được sử dụng trong nghiên cứu này là cố ý trung lập trong từ ngữ của nó. Tuy nhiên, các giá rẻ thảo luận có hiệu quả mong muốn của việc giảm giả thuyết thiên vị, nhưng nó đã không loại bỏ nó. Ví dụ, WTP cho sâu cam ở cánh tay giả thuyết là UGS750 cho mỗi kg, nhiều hơn gấp đôi UGS357 trong cánh tay thực tế, trong khi với giá rẻ thảo luận WTP ước tính thả để UGS553/kg; do đó đáng kể thấp hơn 750UGS/kg, nhưng vẫn cao hơn UGS357/kg. Trở lên thành kiến cũng nhìn thấy trong sự sẵn lòng biên ước tính để trả tiền cho cam và sâu cam giống là tốt, mặc dù một lần nữa những biases thấp hơn là trường hợp trong kịch bản giả thuyết mà không sử dụng một kịch bản giá rẻ nói chuyện.