Conclusions for the Deterministic Analysis

vided, when W is significant, by the order of the various sums of ranks, Rj” [24]. If

one accepts the criterion which the various judges have agreed upon (as evidenced by the magnitude and the significance of W) in ranking the ”n” entities, the best esti- mate of the ”true” ranking of those entities according to that criterion provided by the order of the sums of ranks. This ”best estimate” is associated, in a certain sense, with least squares. Thus our best estimate would be that T-6A should be chosen, for

Rj=32, the lowest value observed, for the ”all DMs + group” sample.

Given the sample size, Kendall’s Coefficient of Condordance (W) was used to check for statistical differences between the individual DMs’ rankings and group rank- ing as a nonparametric statistical method. No significant differences were found be- tween the individuals and group (Kendall’s coefficient of concordance, alpha = 0.05 and 0.01).There is a substantial confidence that the agreement among the DMs in these samples is higher than it would be by chance. All of the probabilities corre-

sponding to the samples under H0 (p-values) associated with the observed value of

W are very low (< 0.01)which enables the null hypothesis,DMs’ ratings are unrelated to each other, to be rejected.

On the other hand, when Kendall’s Tau statistic was used (as it’s presented in ”Additional Analysis”) as the nonparametric statistical method to measure the degree of correspondence and the strength of the relationship between two rankings (i.e. the group ranking versus USAF DMs sampling group ranking, the group ranking

versus instructor DMs sampling group ranking etc.), the results show that there is not sufficient significance to reject the null hypothesis: two sets of rankings are unrelated to each other. However, that doesn’t necessarily mean that the null hypothesis is

true. It only suggests that there is not sufficient evidence against H0 in favor of

H1. There is one important fact to point out here in this additional study. The

sample group rankings that are being compared to group ranking are the resulting rankings of the sum of the mentioned ranks belonging to the individuals who formed the sample group. And these sample groups are a subset of ”all DMs” group. It is not known whether summing the ranks of the DMs’ in those sample group and creating a resulting ranking based on those sums causes a dependency problem. There is not a clear statement relating to this situation in the literature. Therefore, more research on this specific matter can be done as an objective of a future study.

When we examine the individual DMs’ resulting decision for the best primary training aircraft statistics, T-6A has been chosen by 6 DMs, KT-1C has been chosen by 5 DMs, T-37B has been chosen by 3 DMs and T-35 has been chosen by 1 DM. T-35 is in a position of outlier, that is numerically distant from the rest of the data. This alternative has been chosen by the most senior officer of the group. As it has been mentioned in the earlier discussion of group decision making in chapter-2; the older, more experienced, higher ranked are decision makers, the more free they feel themselves to express relatively radical or extreme opinions in comparison to the other average status participants of the decision making platform. That results in

distinctive decisions. When we look at the tables again, T-6A has come up as the ”best estimate” for 5 samples and KT-1C has come up for 1 sample.

The group decision making session did not change the individual DMs’ values and preferences toward certain alternative. It can be clearly observed that the tie between the two leading aircraft remained even when various combination of decision maker sample groups were analyzed. While there is strong concordance among the individual DMs’ decisions relating to the same topic, the group decision making session took three times longer than the average individual DM decision process.

An interesting observation relating to the group decision making process is that, even though it was a group of military personnel gathering to discuss about a topic and come up with a decision and the senior officers are supposed to lead the whole session, it hasn’t been this way. There was no high-ranked group leader pressure during the group session felt by the members of the group. Because, the most senior officer of the group did not express any kind of behavior which could make the other DMs feel like the session was going to be led by himself. However some members of the group did not fully attend the process other than observing and approving the ideas with their gestures while some others eagerly tried to express their opinions in all steps of the process. After creating the wish list at the beginning of the session, when the discussion relating to the values and measures started, it has been observed that some decision makers had quite a big disagreement on most of the values. So, that caused the discussion time to take longer than it was planned. Of note, instructor pilots in particular expressed very similar opinions and thoughts throughout the session.

As the result of the observations and analysis, it can be said that the sam- ples’ decisions highly reflect the preferences of their members. Since, there is such a concordance between the group decision and decisions of the individual DMs who constitute the group, there is no need to spend more time to come up with almost the similar decision in a group environment spending a huge amount of valuable time of the individuals who attend the group meeting. The same process can be handled individually. The members of the group can express their opinions about the topic individually and the process can be handled by an analyst while the members can keep up with their other responsibilities. That would be a very time-efficient decision process at the end.

The results show that there is a high consensus in the samples about which aircraft characteristics are important for the preference of users when deciding for a primary trainer. Turkish Air Force officers were the only group which came up with a different type of aircraft as a primary trainer at the end of the statistical analysis. So, it can be concluded that the samples’ decisions will reflect different requirements in new technology (arm, aircraft, systems etc.) selection resulting from the country, region, force variety. If so, the individual decision makers reflect the parallel values and preferences of the group to which they belong. That means, both individual or group decisions will be close to each other.

Consequently, at the end of our research process; the group seemed to produce parallel decisions with the individuals who constitute it. However, groups appear to be slower in reaching decisions than individuals are. The group decision can be

produced in at least twice the amount of average individual decision makers’s decision process time. It may be much easier and less wasteful of time for us to make a decision as an individual than to involve a group. Sometimes individuals working alone can be more effective than those working together as it has been observed during our research. There were some individuals as it has been expressed before, who preferred not to contribute or present an opinion at all during the group meeting even though they had created their own wish lists independently. They have the opinions about the issue, yet do not feel themselves either comfortable enough or a real part of the group to present an idea. There were also some decision makers who had to try really hard to persuade others while creating the value hierarchy and evaluating measures in order to have the others accepted his opinions since they were presenting relatively different opinions then the majority of the group. And some of those quit trying hard after some point and did not continue contributing to the rest of the process.

The quality of a group decision varies according to the capabilities of its members and how effectively members work together. It is a very important factor to create a worthy result at the end of the group meeting. As we have confirmed during our observations, we can not expect all the individuals in the group to handle the issue during the meeting as well as they do it individually. Because, they are taking the whole responsibility of the result while they are handling it individually. In general, there is an assumption that group provides more important resources since it has greater total knowledge and information than its individual members. But, during our group meeting we have observed the opposite. We have seen that the group

resources are limited to its members’ contribution to this. If a member does not feel comfortable offering new ideas, the resources will be missing from his knowledge, values, etc. Further, the individual behavior of members can affect the quality of the decision. Some tend to dominate the discussion, preventing others from participating. As the result of the analysis part, we can state with strong statistical significance for this case study that the individual DMs can create very close decisions to each other and group. The resulting suggestion for the best primary training aircraft is T-6A Texan II.

After all the alternatives were generated in Step-6 and scored in Step-7, they were measured against each other. Below, Figure 4.1 displays the outputs for ”Group” as an example of a graph of comparing alternatives. The larger the area shown in a specific color correlates to the larger influence that the value has on specific alternative. Examining this figure, we can see that the group values aerobatic training qual- ity the most and debriefing system the least in a primary training aircraft.