From this point it is interesting to take a look on the distribution of topics in the reviews. The figure below shows that people tend to describe Mechanics of the game more frequently than other factors, meaning that they could be satisfied with it or, on the contrary, displeased. People refer to the basics of the game, they want to understand how the game works, how the character is controlled, as this is the first step before actually starting to enjoy the plot.

Figure 21. Topic distribution for corporations (reviews)

Table 11 Topic definitions for corporations (reviews)

The following table demonstrates that Mechanics is also the factor that significantly influence the percentage of positive reviews and metascore of the game.

Table 12 Increase in R-Squared (%) for the regression model (corporations, reviews)

The high percentage increase in allows to conclude that the players judge the quality of the game by how well the basic rules of the game are written and how well a user can understand the algorithms and interpret the information they are given. This point has been tracked as an important one in other researches that focus on the board games. It is said that to make the experience of playing the game the pleasant one, clear instructions are required along with the additional support that might come online. (Pornel, 2011)

Next, it is important to distinguish between the topics that occur in the indie game reviews (Table 13)

From the graph it can be observed that there is a new topic that appears in the reviews of the indie games that is being emphasized by the players (“Graphics”) which concentrates on the visual features of the game, attracting players by the art-style or the design. However, it is not discussed as frequently as the “Responsiveness” factor which concentrates on how well the game is programmed, that all the non-playable characters (NPCs) behave naturally or how glitchy the game is.

Figure 22. Topic distribution for independent developers (reviews)

Table 13 Topic definitions for independent developers (reviews)

The graph on Figure 22 indicated that the factor “Responsiveness” remains the most frequent one that is not only discussed in the reviews of indie games by players but also possess the most influence on the percentage of the positive reviews (Table 14). Again, it is hard to estimate the exact nature of the influence of such factor, it would be wrong to confidently say that games with higher number of positive reviews at the same time have the “Responsiveness” factor as the most discussed in these reviews. Nevertheless, investigating the nature of the influence could be the object of the future research.

Table 14 Increase in R-Squared (%) for the regression model (corporations, reviews)

RQ 2: Which factors are the most influential when making a customer buy a video game which serves as a digital product overlooking its quality?

From the regression models it was possible to distinguish which factors have the highest influence on the number of reviews (or the number of purchases), however, in order to estimate the relationships between factors and the satisfaction of the players with the game more precisely, it is crucial to build a matrix that estimates the relationships between each factor and their effect on each other. As the research deals with categorical data the best estimate of the strength of relationships is Cramer's V which allows to measure the degree of association between two variables. It is estimated between 0 and 1 where values closer to 0 illustrate weak association and the values closer to 1 indicate strong association. The Figure 23 illustrates the relationships between factors for corporations dataset (all factors were included into the function calculation: for the simplicity of further interpretations the ones with “.D” relate to descriptions and ones with “.R” relate to the reviews). The strength of the factor (or the value of Cramer's V) is estimated in colour (close to 0 (low) association presented in red, close to 1 (high) - in yellow) with the level of significance which was calculated for the Chi-squared test that evaluates the statistical significance of the association.

When comparing the dependence of one variable on another between the description factors and factors from reviews, it becomes evident that Responsiveness factor is significantly associated with Complimentarity, Credibility, Personalization and Reach, which mean that when the description contains some information about compatibility of the game, customizable settings or type or genre of the game, it is most likely on the 0.05 significance level that people in the reviews are going to talk about how the game plays, how well the controls work, whether the game physics satisfies the player, or about the bahaviour of NPCs or artificial intelligence.

Figure 23. Association (Cramer's V) between % of positive reviews and factors derived from descriptions and reviews (corporations)

It is also important to note that Complementatiry factor (or the degree of compatibility of the game with player's equipment) is influential on almost all the factor of the reviews apart from Mechanics. Hence, it turns out that when the description mentions some additional game features that are availbale in the game (e.g. multiplayer), the reviews will most defenitly be revolving around the issues of the suitable game response, or the story of decision-making process as well as the possibility to change the settings to the player's needs. Another strong connection between the factors lies in the relationships between Mechanics factor from the reviews and its affection by the Content and Credibility factors on quite a significant level. The Gameplay is strongly affected by the Complementarity factor and Customization depends on Content.

However, the most important relationship estimation that this analysis yields is the existence of the effect of each factor on the percent of positive reviews. Looking closely at the output, it is possible to notice that the percentage is strongly affected by Reach factor on the 0.05 significance level. This factor also is the most influential on the number of purchases of the game (or the number of reviews) which was found when creating a regression model. By looking at the Figure (17) it might be concluded that if the Reach factor is empasized in the description of the game, then it is most likely that this game has a high number of purchases but it cannot be of the best quality, as the reviews for this game are mostly negative and concentrate around the problems with the inadecvate behavior of characters or strange game physics. Taking for example the game called Raid: World War II, which was assigned by the model to the Reach topic. The game does not have a large number of reviews (1692) and average per cent of positive ones (53%). The description of the game concentrates partly on partraying what the player will encounter in the game and connecting to possible player's interests. Here is a part of the original description:

“RAID: World War II is all about teamwork and strategy during intense firefights filled with adrenaline. In RAID: World War II, you are fighting the enemy from within. You are up against tough odds, but with enough fire power, determination and recklessness anything is possible. Fight the good fight but fight dirty.” (Raid: World War II, 2016)

The most helpful review was allocated to the Responsiveness topic, and the following citation illustrates that a player does in fact talk about the behavior of the characters and the general logic of the game response to player's actions:

“Here's a quick rundown of what I thought about Raid WW2:

-The diesel engine: all of the problems with payday 2 has carried over to raid: bugs, glitches, crashing, desync, optimization issues galore

-Friendly AI behave poorly and enemy AI does questionable things like walking through walls and shooting through walls

-The AI does not respawn at all for the rest of the raid if you don't revive them

-Harder difficulties still suffer with enemies being unreasonable bullet sponges

-Adding with desync, this makes stealthing very frustrating when playing with other people, but you are always geared for loud so at least you can stealth parts of the raid to make the rest of the raid easier to complete” - by Inspector Dosh (June 14th, 2018)

The next factor that affects the percentage of positive reviews is Content which matches to the fact that this factor also was influential on the number of reviews (purchases) of the game. The graph in the Figure (17) tells that the games which used information about the world and the environment with which the players will encount in the game also had high number of purchases with low percentage of positive reviews and vice versa.

In terms of the reviews, the connection is easy to follow between the percentage of positive reviews and Mechanics (on the 0.0261 significance level) and Gameplay factors (on the 0.0228 significance level). However, once again, current modeling does not allow to judge on the nature of the influence of one factor on another for the reviews section.

The same analysis was applied for the independent developers dataset. After creating the matrix, the output of the graphical representation can be observed in the Figure below. The main assocciations between factors show that games with descriptions revolving aroud “Reach” factor cause the reviewers to talk about “Graphics”. It is not surprising, as in indie games descriptions, one of the ways to appeal to the interests of the players is by mentionaing the art-style of the game. There is also strong association between the “Incentive” and “Customization” factors that surfaces when descriptions of the game promise some achievements or awards, and reviews focus on the opportunity to adjust the setting of the game for players' needs. What is more, when the indie game description mentions tha genre of the game, the players tend to talk about its' visual representation. The “Content” factor, or the world atmoshpere depicted in the descriptions, starts the discussion in the reviews about the “Customization” and “Graphics”.

Figure 24. Association (Cramer's V) between % of positive reviews and factors derived from descriptions and reviews (independent developers)

The comparison of the dependence of the percentage of positive reviews and the factors yielded that there is strong significant association of the “Reach” (on the 0.0134 level) and “Resposniveness” (0.0484 level) of description factors, which were also influential on the number of the purchases of the game. Talking about reviews, the most significant associations were found for the “Content” and “Gameplay” factors on their ifluence on the positive reviews. Taking, for exampl,e a game called “Mashinky” that has comparatively high for an indie game number of reviews (1070) and relatively high per cent of positive ones (85%). Its description was allocated to the “Reach” factor and talks about the graphics in the game:

“Mashinky is a brand new transport strategy game from Czech developer Jan Zeleny. Zooming through gorgeous landscapes, utilising a traditional isometric construction mode and mastering a unique board game-like gameplay, you'll find yourself immersed in the task of building your own transport empire. The game is a unique blend of realistic graphics combined with an isometric construction mode and boardgame-like rules.” (Mashinky, 2018)

The game's most helpgul review also focused on the dascription of graphics and visuals:

“Even the tiniest details are incredible already. Long, lean stripped down tree-trunks with their rough, detailed bark were loaded into my lumber wagons, and almost every part of the locomotive is animated, detailed in colour and with realistic everyday-grime texturing. Dusty wagons collected my coal. Trains in the distance were in soft focus until they began to take shape on their approach, with great steam effects and lovely animations. Carriages looked old and rustic. It is for all the world like the genius simplicity of games like OTTD with their easy grid layout being joined with games with today's much more realistic graphics and textures, giving the best of both worlds. It is the rail tycoon that, on surface, is showing signs of one day becoming the game I've dreamed of for a very long time.” - Bad Whippet (November 12th, 2018)

Still, the existence of strong association between the factors does not allow to make conclusions about the nature of the relationships and their influence on each other.

In the section of theoretical foundation and the methodology of the current study it has been established that LDA method has been chosen as apropos to the goals of the research. However, is has also been mentioned that apart from LDA there is another method - STP - that could have given the output that the researchers have been intended to get. The application of this method, even though could have led to the approximately same results, would substantially decrease the input of the researchers. STP method is an automated one in contrast to the LDA. It means that the allocation of the topics is not under control or supervision and cannot be done manually. As the result, the process of defining each topic along with the selection of the examples in terms of the most applicable words becomes difficult due to the automation of the model which does not allow the researcher to interrupt. In addition to that, it is important to bear in mind that the STP model does not provide the opportunity for the extensive manipulation of internal topics and word occurrence patterns for the statistical analysis. This justifies the choice of the LDA method among the two algorithms.

The extensive theoretical background analysis offered ten factors that are exploited in the digital marketing area. The list of the factors identified has become a unified collection of the elements of digital marketing that different authors name as most exploited by companies. Different authors discussed how companies exploit mentioned factors. For example, Barnes (2002) outlined that rapid development of the digital industry cannot be put along with the prospects of all of the customers. He argues that while some companies strive to remain in line with the latest system updates and software development, others do not. Therefore, customers have to be aware of the product compatibility with their opportunities. Others mention that for digital industry it becomes common to implement some additional information about the product that is not relevant to the product directly but rather supplies extra details that not all customers are interested in (Fransen, Verlegh, Kirmani & Smit, 2015). However, not one of the authors delve deeply into the research of the factors exploitation specifically in the video game industry. Striving to cover this gap, in the current paper it was found out that only six out of ten found in the academia factors were identified in the video game specific field. The allocation included such factors as Reach, Content, Credibility, Complementarity, Incentive and Personalization. One of the reasons why other factors were not detected in the promotion materials is the fact that they are related to the internal operations in the companies. For example, Cost factor refers to the expenditures on the marketing campaign, and Frequency require calculating how many messages the company has sent to the consumers while the promotions operations held place. These factors, hence, were the most unlikely to be met in the descriptions of the product that would appeal to the customers.

The six factors identified in the first place in the promotion materials of different game developers allow to accept the fact that companies do exploit some unified methods to attract customers attention to the digital product. In fact, the most frequent appeal is built by focusing on the Reach and Content factor in big corporations and Credibility from the independent developers. This means that big companies tend to draw customers' attention to the fictional world that a customer can experience or emphasize the possible connections to the players' interests with what a game offers (e.g. highlighting that the game was created as a part of franchise or stating the possible theme of the game such as “school” or “history”). On that note, it is important to mention that in the research of digital marketing some authors pinpoint that by describing unique properties of the product, the inside features that only this product possess can attract more attention from the customers to the product (Oakey, Cooper & Biggar, 2018). Credibility, the most exploited by independent developers factor, offers a focus on the genre of the game, making it understandable for the player what to expect from the game and establishing a baseline of the in-game features and mechanics with which the player will encounter. Concerning this finding, some studies suggest that creating an explicit and clear categorizations and labelling of the digital product can help customers orient better in the environment of the information overload (Nylйn, & Holmstrцm, 2015), which is precisely what independent developers are trying to do. Thus, the main difference between most frequently used factors is that corporations appeal to the content of the games, their unique features, whereas independent developers focus on identifying the genre and type of the game. This may be one of the reasons why indie games do not get the same response as the games produced by corporations.

Talking about the other factors identified in the video game industry, it is crucial to note that all of them have slightly different, more specific, meaning compared to the general definitions relating to digital marketing drawn from the theoretical background. Complementarity factor referred to the additional features of the game that a customer can exploit, or compatibility of the equipment with the game system requirements. Incentive factor focused on the referred to the in-game rewarding system that would allow a player to get some substantial results from playing the game. Concerning Personalization factor, it is associated with the availability of the customization of the settings so that it was comfortable for the player to adapt to the new atmosphere. However, these factors are not used by both types of companies as frequently as Reach, Content and Credibility.

Conclusion

The conducted research allowed to identify the most influential promotion factors that are video game industry specific, hence, covering the gap in the existing studies on the topic of digital product quality. The list of existing digital promotion factors was gathered from the different sourced and united under one framework for further estimation. The list of ten factors that were allocated by different authors as quite essential in marketing of digital products was crucial to arrange to further investigate their importance in a more specific industry - video games in this paper.

The video game industry presents so much interest in terms of marketing of the digital product as it is an emerging market that only recently started to gain more and more attention because of the dramatic increase in revenues overall and the fact that every third household on average in a developed country has been engaging in video gaming for the past couple of years. However, only recently the industry was faced with the drastic change of the product quality, leaving the general public dissatisfied with the product offered by corporations. That is why customers turned to independent developers, who have fewer financial resources to promote the game as the bulk of them is invested into the technical developments so that the players could get the most pleasurable experience. This research proved that there is in fact a significant disparity between not only the numbers of sales of the games produced by corporations and independent developers, but also between the quality of the digital products delivered for the customers. At the same time, the sales of big corporations tend to stay rather high compared to that of indie games. This fact prompted further investigation into the means with which corporations appealed to the customers, and one of the most influential ways, as other studies suggest is through marketing (Anderson, 2011; Paswan, Blankson & Guzman, 2011; Jaworsky, 2018).

The intangibility of the digital product makes it difficult to estimate its quality, and that is where customer opinion plays a crucial role. Customers' judgement, even though at times subjected and too specific individually, creates a bigger overall picture when analyzed aggregately. That is why the analysis in this paper revolved around customer reviews about the product they purchased and utilized. During the analysis, it became evident that organisations (both corporations and independent ones) operate in a slightly different dimensions compared to the actual customers. It means that customers and organisation exploit different terminology and focus on different perspectives. Companies tend to promote the game and customers, on the other hand, evaluate its playability and concentrate on different factors. This fact was overcome by searching in the literature for the factors that related to the games themselves, their internal factor, and that is where usability principles of games have been found. Thus, reviews and game descriptions acquired different factor labels, between which it was also possible to find the degree of association to estimate their influence on each other.

It is crucial to understand the limitations that the research is subjected to. Since this paper partly bases derivation of conclusions on the individuals` opinions, which in case of the study remain the reviews posted on the game distribution platform, the presence of bias is unavoidable. The reviews of real people, or the players, display personal experience, emotions and feelings to a certain extent, even though the reviewer intended to hold the position of impartiality. In order to eliminate or, at least, to decrease the significance of this problem, the reviews have been selected in accordance with their helpfulness from the perspective of other customers. Due to the fact that each review can be evaluated by other users as helpful or not helpful, it allows to sort the reviews and distinguish the ones that hold value for the research (the process of data collection is also described in Appendix 5). This helps to get a better overall impression of the general public opinion and eliminate the bias of the researcher who picks the reviews and decrease the bias that is put within the reviews themselves. What is more, as it was discussed in the methodology section, the analysis of reviews has become quite popular in the literature, and as this research concentrates on the quality of the end product, the best source to judge this quality is customer opinion (Ivory, 2006).

Another limitation pertains to the fact that it is impossible to establish exact number of purchases of the certain game due to the lack of such information. The researchers assume that the number of purchases is proportional to the number of the reviews left for the game since reviews on the Steam.com distribution platform can be left only after the purchase of the game. This number might not be the same in reality as some players prefer not to leave any comments or reviews after the purchase. However, as far as the researchers aim at analyzing the general trends on the market, this estimator is considered to be feasible to use as it shows the minimum number of purchases happened for sure and, hence, remains the closest to the market situation. Besides, in the sphere of marketing research, methodology of the reviews analysis is widely applied to extract customers' opinion, and the conditions in which it is relevant to exploit such a methodology suit the current research as well, hence, using such source of information about market trends becomes reasonable.

One more limitation that refers more to the outcomes of the research results is that the definitions of factors and the words allocated to each topic are video game industry specific which might make it tricky for construal for other digital industries. Nonetheless, this does not present a problem since the definitions can be shaped in accordance with the needed industry due to their flexibility in interpretation by analyzing the conditions in which chosen industry operates.

Apart from that, data constrains do not allow the analysis of a wide range of different variables which lead to the slight increase in the effect of the influence of the chosen variables. However, the results still depict the market situation as the regression models created show high numbers of and appropriate level of significance which allows to establish general situation and draw proper conclusions. One more potential limitation refers to the fact that the research concentrates on the factors used for promotion of a game. Therefore, it is not quite clear to what extent the findings generalize the factors to other signals that the developers intend to send to the players (such as to increase brand awareness, appeal to the professional reviewers, etc.).

As a result, content analysis of the game descriptions of famous companies and independent game developers revealed the main factors that corporations tend to employ as their promotion signals. Those signals are well-received by the customers that lead them towards making the purchasing decision in favor of those games. Indie games` descriptions are, on the contrary, straightforward in their appeal to the customers that makes them less favorable in terms of the customer decision to play. The proposed list of the factors illustrated in the Description of the results section would serve as a first step towards the enhancement of the marketing campaign of the games produced by independent developers.

The degree of influence was estimated with the regression modeling to find the dependencies between the number of purchases and the promotion factor. For both types of developers, the two most influential factors were Content and Reach with the slight difference of Reach being more influential for the sales of games produced by corporations and Content resulting in being more influential for independent developers' game purchases. It is important to note that Corporations habitually exploit the most influential factors in their marketing campaigns, whereas independent developers fail to do so, concentrating on one of the least influential factors - Credibility. The analysis showed that for the players the most important factors remain the same, because the reviews for both types of games put more emphasis on the Content and Reach factor. These characteristics showed strong association with the quality of the game (the percentage of positive reviews). This means that customers pay more attention to the atmosphere of the game and on how well this atmosphere correlates with their general interests and by that the players judge the quality of the game. Thus, when the customers see that the description of the game illustrates expressively features connected to the Content and Reach factor, which they consider, the most important in the game, they tend to buy such games more often than the games that put no such an emphasis. This was found from the customer behavior with the games produces by corporations. For the independent developers, unfortunately, it is hard in the conditions of current research to assess the nature of the factor influence on the purchases of their games, which could be one of the possible directions for further research.

At the same time, the analysis of game descriptions of independent game developers detected that even though the developers highlight the same set of factors as corporations, they put different focus on each one. They put more emphasis on the visual representation rather than the atmospheric feel of the game and the description of the world and the story. This means that despite being on the right path, they, nonetheless, utilize the factors in a different way that leads to less effective results in terms of their performance. The players, on the contrary, tend to underline the importance of those factors. Hence, it is safe to say that by shifting the stress in their marketing campaign on the proper factors, independent developers may increase the effectiveness of their performance and get the deserved recognition of their games.

The results of the current research are enabled to illustrate the independent developers their flaws in marketing campaigns. Since those developers do not possess the financial ability to bolster their ideas, the application of the found in this study factors might become useful while appealing to the customers in an attempt to cultivate new ones and maintain the previous fans. This also might help independent developers to perform better on the market among other competitors who have established their brand and received credit for their previous games. All in all, the set of factors is designed to provide the primary knowledge regarding the current situation on the video game development market, and to help independent developers in increasing the effectiveness of their marketing campaigns.

On the other hand, the results of this work may also serve as an example in distinguishing promotion success factors in other digital industries that also offer intangible product the quality of which is difficult to measure by traditional means. Even though the methodology might not be applicable for the research in some industries, the results of the current study will serve as a basis for the theoretical foundation of the future research. In addition to that, it was mentioned in the theoretical foundation section of the current research that the problem of the companies which apply deceptive techniques in their performance touches the ethics issue. Ethics and the unfair competition establish the situation when the advantage is unevenly spread among the companies. This problem might become another direction of the future research as it opens a field to discover the exact reasons why ethics is important and the consequences of its violation to big corporations on the exact cases. The full list of potential directions of the current research may be found in the table below.

Table 15 Future research agenda of the current research

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