From what I read from the journal I think, there I a few of factors of peer assessment for this oral presentation using a large amount of score Management based on student performance during their presentation. This assessment can be done by the student response system using the Rubric constructed based on the nine features of the three content-related features, the five attributes related to the delivery and one overall feature.

Furthermore, this response system is also used in the last session of learning to collect answers to questions about student's self-efficacy and perceptions of their learning process including difficulty assessing their peers in the classroom.

In addition, they use factor structure (Main Component Analysis) and reliability (Cronbach alpha) from two components of presentation, content and delivery skills.

Besides that, In this case it is important to know the characteristics of the assessors who are responsible for assessing students. About student characteristics is self-efficacy and scores are obtained from all participants. Most participants take decisions as both roles. This helps to explore the relationship between self-efficacy and scores, and the relationship between self-efficacy with the scoring score provided.

To peer. To explore the relationship between self-efficacy and "awarded" and "accepted" scores, their evaluation is built on two scales ie self-efficacy related to 'content' criteria and self-efficacy related to 'delivery'.

Following the hypothesis obtained by them is that good narrators are also good assessors, we calculate the relationship between these in relation to the performance scores.

According to the assumed relationship between the difficulty of the assessment it is deemed likely to avoid the unexpected extreme score. They expect negative relationships between the perceived difficulties, and the standard deviation of scores given to peers.

After two studies, finally, they are trying to determine whether students become better assessors because of their assessment practices. They compare the distribution of scores between first and last sessions.

 It is hypothesized that the distribution of scores (standard deviation) for an oral presentation is larger at the start than the last session. Their assumption is that participants in the last session understand better features, as they can compare scores given by different assessors to the same oral presentation

In an assessment of students oral presentation, students can also can play role as assessor and assesed but this raises questions about the reliability and validality of assessment and the attitudes of students towards peer assessment.

 

From the conclusion and recommendations based on the journal there are according to the establishment of a learning community where students are connected with each other as doers and evaluators. Next, principal component analysis revealed that the assessment instrument has a good internal consistency and a
construct validity in line with the underlying components ‘content’ and ‘delivery’. Besides that,  a substantial proportion of the variance in the assessment scores can be explained by the factor assesses. Furthermore, students perceptions about the use of peer assessment are
very positive. Also recommended that educators try
to promote self-efficacy because it is an important student characteristic. Assessors with a high self-efficacy level tend to give more extreme scores and higher scores. Moreover, the assessment process and attributes more time to the
training of the assessors.
Future research could also study the learning effect of peer assessment on consequent oral presentations and see if skills are enhanced by observing peers.
 

This research tries to certify about the reliability and validity of peer assessment of oral presentation used as tools in improving students' way of doing oral presentation how it effects others in learning and a good technique on how to develop positive self-efficiency. 
Research results mentioned briefly that learners with positive efficacy are more likely to work harder, persistent and attain higher achievement levels by knowing the standard and difference between a good and a weak presenter as a good presenter may know the higher qualities of presentations.

I think the problem faced by students during oral presentation from the journal that i read is students need assessment by peers so students are more confident to do oral presentation. This is one of the new alternatives in strengthening the role of assessment center of oral presentation.

From the analysis and result based on the journal of peer assessment of presentation skills,there are two component of the presentations skills, content and delivery that builds for the principal component analysis. Professionalism is correlated to a stronger extent with delivery than content from the result that been show.