By also taking into consideration Sects. 2, 3, and 4, this section shows the estimation results of Eq. (1). We use PS3, Wii, 3DS, and PSP for the console game \(Y_{ijt}\), which is the dependent variable. The reason for this is that these games are the top two consoles with a high play rate for home video game consoles and handheld game consoles. Furthermore, their developers are different. This situation is shown in Table 4.
Table 4 Characteristics of the video game consoles
Before conducting our estimation, we need to find instrumental variables (IV). The required condition of the IV is correlated with independent variables, but is not correlated with error terms. We use whether or not individual i owns hardware k (k is other than j) as the IV of each endogenous variable (the vectors \(C_{it}\) and \(P_{it}\) do not include the console game j) and whether or not individual i plays the video game in hardware k at time t. Whether individual i owns hardware k affects whether or not s/he plays the video game on that hardware k, but does not affect whether s/he plays the video game on console j, so owning hardware is correlated with the independent variables, but is not correlated with the error terms. For these reasons, whether or not individual i owns hardware k is appropriate as the IV.
Tables 5 and 6 show the fixed-effect method estimation result of Eq. (1). In Table 5, the coefficients are from the standard fixed-effect method, and from the IV fixed-effect method in Table 6. In Table 5, the column < 1 > shows the result when the dependent variable is PS3; column < 2 > shows the result when what is? Wii; column < 3 > shows the result when what is? 3DS, and column < 4 > shows the result when what is? PSP. In Table 6, columns < 5> ~ < 8 > correspond to < 1> ~ < 4>. When we estimate Eq. (1), every dependent variable is removed from the independent variables. In addition, the sample represents the owners of the console games as the dependent variables: in column < 1>, the results refer to owners of PS3, and in column < 2>, owners of Wii.
Table 5 Estimation results of the fixed-effect method
Table 6 Estimation results of the IV fixed-effect method
By comparing Tables 5 and 6, we see that Table 5 does not use the instrument variables for the smart devices, and the video game consoles have significantly positive coefficients, so most of them are in complementary relationships. However, due to time restrictions, it is difficult to really see if there are complementary relationships. Since not controlling the endogeneity problem gives rise to overestimations, we adopt the results in Table 5.
As shown in Table 6, most of the parameters of the month dummies are significantly negative. These dummies are based on December because consumers tend to play the console games more during the Christmas season than during other months.Footnote 9 On the other hand, August, September, and November have significantly positive coefficients. This reason for this is that there is a summer vacation in August, and university students have summer vacation and “Silver week” in September, so these results are consistent. In November, the Christmas sales battles start, and consumers respond more sensitively than in December when the new popular software titles are released in the last week.
Regarding the parameters of video game consoles, all variables in all columns are significantly negative or insignificant except for PSP in column < 5>, so they have the substitute effect on video game consoles or do not have any effects. In other words, playing the video game consoles causes a decrease in the play rate of the other consoles. PS4, especially, has a strong substitute effect (0.236) compared to PS3. However, PSP is in a complementary relationship with PS3. This result is caused because of PS3 remote play of PSP or the Internet via PS3. All these results can be interpreted naturally, so the models are reasonable.
All of the smart devices, which are the most important variables in this study, have significantly negative effects on Wii and 3DS. In addition, Android has a significantly negative effect on PSP. However, most smart devices have no significant impact on PSP and PS3. From these estimation results, we see that smart devices have substitution effects on Wii, 3DS, and PSP, but the effects on PSP are limited, and they do not have effects on PS3.
By comparing the type of game console, i.e., the home video game consoles and the handheld game consoles, we see that the substitution effects are up to approximately 0.103 on 3DS while up to approximately 0.056 on Wii. Although the effects on PSP are up to 0.031, there is no effect on PS3. These results imply that the substitution effects of mobile games on the home console games are smaller than on the handheld console games. For this reason, both the handheld game consoles and smart devices are superior in portability, so players can use them at any time and in any place. It is likely that the mobile games will replace the handheld console games because they can be played on a train or bus while commuting, or played with friends anywhere. However, the advantage of the home console games is that the games are richer in content and have more interesting characters, thus it is not likely that mobile games will replace console games.
Second, when comparing the developers, SIE and Nintendo, we see that the substitution effects on console games which are played on SIE’s video game consoles are larger than on console games which are played on Nintendo’s video game consoles. The reason is because both the main users of console games played on Nintendo’s video game consoles and the main users of mobile games are casual gamers. On the other hand, most SIE game users are senior and core gamers, thus it is hard for them to change from console games to mobile games. Langlotz et al. [14] discusses how Microsoft and SIE produce high-technology products for the traditional hard-core gamer, while Nintendo’s focus is on less technologically advanced targets, that is, casual gamers. Encarnaçao [15] also implies the same proposition. Moreover, Rayna et al. [7] points out that the common characteristics between Wii and the mobile games are that their users are casual gamers.
All in all, the substitution effects are as small as 0.1 at the maximum, and the effects on PS3 and PSP are almost negligible. Therefore, the following hypothesis in Sect. 2 is accepted.
Hypothesis: Mobile games have few substitution effects on console games.