Is AI Better than Humans? Unveiling the Boundary Conditions Under Which Virtual Influencers Outperform Human Influencers in Endorsing Sustainable Products
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe article Is AI Better Than Humans? Unveiling the Boundary Conditions Under Which Virtual Influencers Outperform Human Influencers in Endorsing Sustainable Products is well described and contextualized concerning previous and present theoretical background on the area. I recommend including the aim of the study in the introduction.
The manuscript is original and engaging, and the overall merit is high. The references used are relevant and well-used in the discussion. However, I recommend following the structure of the journal sustainability related to the present introduction, material and methods, results, and discussion and conclusions. After reading the document, I needed clarification on the quality of the structure of the author's present manuscript because many chapters and subchapters are described. For example, I recommend only one methodology and discussion.
Comments for author File: 
Comments.pdf
Author Response
Please see the document attatched
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsPeer Review Report
Title of the Manuscript:
Is AI Better Than Humans? Unveiling the Boundary Conditions Under Which Virtual Influencers Outperform Human Influencers in Endorsing Sustainable Products.
1. Contribution and Originality Assessment:
The manuscript addresses an innovative topic, particularly relevant given the rise of artificial intelligence technologies and their growing use in marketing. The study offers a compelling investigation into the conditions where virtual influencers (VIs) outperform human influencers (HIs) in promoting sustainable products. This research framework represents a valuable contribution, particularly given the current gap in literature regarding the specific role of VIs in sustainable marketing.
Recommendations:
- Further clarify how this manuscript distinguishes itself from prior studies.
- Emphasize the practical applications of this research within the field of sustainable marketing.
2. Clarity of Objectives and Hypotheses Formulation:
The objectives are well-defined, and the hypotheses follow a coherent logic based on theories such as dual-process theory. The manuscript identifies two main research questions (RQ1 and RQ2) regarding the differential impact of VIs and HIs, as well as the conditions for VI success in sustainable products. Hypotheses H1-H4 are well formulated but could be synthesized to improve readability.
Recommendations:
- Simplify the presentation of the hypotheses for greater readability.
- Ensure that all hypotheses are directly related to the study’s results to avoid overly broad interpretations.
3. Methodology Rigor and Relevance:
The manuscript employs a solid methodological approach, divided into two distinct studies to test the hypotheses. The first study focuses on perceived credibility and parasocial relationships for VIs and HIs, while the second examines the interaction between type of advertising appeal (emotional vs. rational) and product involvement level (low vs. high). This structure allows for in-depth analysis, though certain elements could benefit from further clarification.
Recommendations:
Provide additional explanation for the methodological choices, particularly participant selection criteria and the rationale for choosing these specific products (low and high involvement products).
- Clarify how control factors (e.g., visual similarity between VIs and HIs) were managed.
- Add more detail about the sampling process and justify the use of the selected survey platform (Credamo).
4. Results Analysis and Interpretation:
The results are well documented and presented with appropriate statistical rigor. The mediation (bootstrap process) and moderation analyses show a good level of precision in the statistical approach. The figures and tables are clear and help illustrate the differences between VIs and HIs based on advertising type and product involvement. However, interactions between influencer type, appeal type, and product involvement could benefit from deeper interpretation for non-specialist readers.
Recommendations:
- Include a more detailed discussion of the practical impact of the results, particularly within sustainable marketing and commercial applications.
- Provide a more nuanced explanation of how observed differences between VIs and HIs influence perceptions of product sustainability.
- Discuss implications of the results regarding the perceived credibility of VIs in contexts where authenticity is crucial.
5. Organization and Presentation Clarity:
The manuscript is well-structured, but some sections, such as the literature review, could benefit from a more concise synthesis. Paragraphs in this section sometimes contain redundancies, which can affect the reading flow. Overall, the style is adequate, but simplifying and clarifying certain sections would make the document more accessible.
Recommendations:
- Reduce the length of the literature review by removing redundancies and synthesizing key studies.
- Clarify specific or technical terms when they are first introduced to ensure greater accessibility for a wider audience.
- Arrange the sections to follow a logical progression from research question to results.
6. Study Limitations and Recommendations for Future Research:
The authors mention some limitations, notably the lack of consideration for cultural differences, which limits the generalization of results to international contexts. The conclusion section could be enriched with concrete proposals for future research in multicultural and longitudinal contexts.
Recommendations:
- Suggest future studies exploring cultural differences or the perception of VIs across different social contexts.
- Recommend alternative methodologies for studying the effect of interactions between product and influencer type on other aspects of purchase decision-making.
- Consider longitudinal studies to examine the evolution of consumer attitudes toward VIs.
7. Compliance with MDPI Style and Reference Quality:
The manuscript generally adheres to MDPI style, and the references are appropriate and current, though one or two more recent sources could strengthen the theoretical foundations section. Figures and tables are well integrated and align with MDPI guidelines, with clear labels and captions.
Recommendations:
- Verify that all citations adhere to Sustainability MDPI’s required format.
- Add recent sources to certain parts of the literature review, particularly on dual-process theory and case studies involving VIs in sustainability campaigns.
8. Content of Images in Chinese:
Some images contain elements in Chinese, which may present a barrier for non-Chinese-speaking readers. To ensure that the manuscript is accessible to an international audience, it is recommended to add English translations.
Recommendations:
- Translate the essential Chinese text on key images into English, especially if they contain crucial study information.
- Add English captions for each figure, explaining the visual content and facilitating interpretation by readers.
- Consider adding an appendix describing the content of images in English if these are used as advertising stimuli in the study.
9. iThenticate report: 18 % index of similarity
Analysis of similarity rates: A similarity percentage of 18 % is considerably elevated and necessitates thorough scrutiny. Similarities arising from the reuse of technical terminology or standardised definitions may be deemed acceptable if appropriately cited. Nonetheless, portions such the introduction, methods, or conclusion must be original and not directly replicated from prior papers without substantial rephrasing.
Source control: It is imperative to verify that any references to analogous works are accurately referenced. Authors must rephrase any borrowed sections to prevent inadvertent plagiarism and enhance the manuscript's originality.
Recommendations:
· It is recommended that authors revise the reported portions, focussing on the essential components of the article, and verify that all sources are accurately cited.
10. English Language Quality
Overall, the manuscript's English is predominantly clear, however it would benefit from polishing to enhance fluency and precision. Occasional odd words, overly complicated sentences, and small grammatical faults may impede readability.
10.1 Specific Issues:
Sentence structure: Some sentences are too long or complicated, which affects the clarity of the message. For example, dividing lengthy sentences into shorter forms would enhance readability.
10.2 Grammatical and punctuation errors: There are minor grammatical flaws, especially regarding article usage and sporadic punctuation mistakes.
10.3 Tense consistency: The manuscript inconsistently alternates between past and present tense in many instances. Maintaining tense consistency throughout would improve clarity. I suggest a comprehensive proofreading by a native English speaker or a professional editor to refine the language. This will enhance the manuscript's overall clarity and guarantee that the concepts are conveyed distinctly and efficiently.
Language Rating: Moderate revisions needed.
Final Remark:
This manuscript is well-structured, relevant, and makes a significant contribution to the field of sustainable marketing and digital influence. To enhance the impact of the document, a few adjustments are recommended, particularly in presenting hypotheses and results, and in clarifying the literature review.
Comments on the Quality of English LanguageOverall, the manuscript's English is predominantly clear, however, it would benefit from polishing to enhance fluency and precision. Occasional odd words, overly complicated sentences, and small grammatical faults may impede readability.
* Specific Issues:
Sentence structure: Some sentences are too long or complicated, which affects the clarity of the message. For example, dividing lengthy sentences into shorter forms would enhance readability.
* Grammatical and punctuation errors: There are minor grammatical flaws, especially regarding article usage and sporadic punctuation mistakes.
* Tense consistency: The manuscript inconsistently alternates between past and present tense in many instances. Maintaining tense consistency throughout would improve clarity. I suggest a comprehensive proofreading by a native English speaker or a professional editor to refine the language. This will enhance the manuscript's overall clarity and guarantee that the concepts are conveyed distinctly and efficiently.
Language Rating: Moderate revisions needed.
Author Response
Please see the document attatched.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsKeep on with the good work.
Author Response
Please see the document attatched.
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Author
The manuscript can be considered for publication.
Reviewer 2 Report
Comments and Suggestions for Authors1. Contribution and Originality
The authors appear to have addressed this adequately by highlighting unique contributions and providing practical examples.
2. Clarity of Objectives and Hypotheses
The authors have followed the recommendations well, clarifying the hypotheses and ensuring their direct relevance to the results.
3. Methodological Rigor and Relevance
The authors have comprehensively addressed this point by adding essential methodological details and justifications.
4. Results Analysis and Interpretation
The responses are well-developed and meet the reviewers’ expectations regarding depth and practical relevance.
5. Organization and Presentation Clarity
The authors have successfully followed the recommendations by structuring and clarifying the text for improved readability.
6. Study Limitations and Future Research Recommendations
The authors have addressed this recommendation well by proposing concrete future research directions.
7. Compliance with MDPI Style and Reference Quality
The updates to citations and the addition of relevant sources meet the requirements.
8. Content of Images in Chinese
The authors fully met the recommendations, making the images accessible to non-Chinese-speaking readers.
9. Similarity Index
The reduction in similarity indicates a good effort toward originality, though a final check for compliance may be advisable. (14 per cent is acceptable)
10. English Language Quality
The language adjustments seem professionally handled, addressing the journal’s language standards.
Comments for author File: 
Comments.docx
