Subplots of Fig. 5 show the average variation in the mobility pattern with respect to each criteria (C1–C5) in all the selected states during each of the lockdown periods (L1.0–L4.0). The first four criteria (C1–C4) since it represents the decrease in trips with reference to the baseline period, a negative sign is associated with each attribute, as evident from Fig. 5. While being in residence is also a measure of adhering to lockdown policy, the increase in time spent is captured as a positive value.
The trips made to retail and recreational places in all the states are comparably lower than to the other category of places (C2–C4). However, trips made to the retail and recreational places during L2.0 has significantly decreased by 11.4% compared with trips made in L1.0. A similar trend is observed in the majority of the states over time. Delhi, Gujarat, Haryana, Karnataka, Kerala, Madhya Pradesh, Maharashtra, Punjab, Rajasthan, and Tamil Nadu are exceptions where these visits increased.
On average, in all states, an increase of 25.5% in trips to groceries and pharmacies during L2.0 compared with L1.0 is noticed. Subsequently, it later increased to 54% and 72% during the L3.0 and L4.0 periods, respectively. Mean variation in trips made to parks during the lockdown 2.0 is reduced by 28.7% (except in Kerala and Bihar), Further a decrease of 26.4% and 20.3% during L3.0 and L4.0, respectively, with reference to L1.0. The scenario in West Bengal is slightly different, where a slight increment of 1.2% in the trips made during L2.0 is noticed and then followed a decreasing trend. The trend in variation of trips to workplaces is observed to be similar, as observed in the case of groceries and pharmacies. The mean increase in trips is 9.4%, 28.2%, and 38.5% with respect to L1.0, in the period of L2.0, L3.0, and L4.0, respectively. In contrast to the trend noticed in the case of workplaces, the time spent by the civilians at their respective residences started declining as the lockdown period extended, which is obvious. However, the trend in Delhi, Madhya Pradesh, Tamil Nadu, and Uttar Pradesh during L2.0 is an exception where there is a mean rise of 1.0% in the time spent at home.
The evaluated day-wise LBI corresponding to each selected state using the proposed methodology (TOPSIS) is shown in Fig. 6.
There is a significant increase in breaching activities in all the considered states. The subplots of Fig. 6a represent the variation of LBI in each of the states during successive lockdown phases. The evaluated LBI is with reference to the ideal situation where citizens strictly adhered to lockdown policies. Values close to 0 indicate negligible breaching activities, while the higher magnitude is proportionate with the intensity of breaching.
The evaluated LBI fields are observed to be relatively high on the weekends, as can be seen as little spikes. These spikes do not reflect the actual breaching activities on Sundays. Since, in general, the variation in trips is relatively low, which, when compared with the ideal solution, gives a high offset value, which contributes to the spikes. Thus, caution should be exercised in dealing with the data on Sundays. An LBI variation of nearly 12% on Sundays compared with the other days of the week is noticed. Such variation gradually decreased as the week progressed.
The mean LBI of all the considered states is 53.21, which reflects notable mobility within all the lockdown periods. Figure 6b depicts the percentage rise of breaching activities in terms of LBI with respect to L1.0 for all the states. Though an average rise of 3% breaching activities with respect to L1.0 is noticed in all the states, a decreasing trend is noticed in Delhi and Tamil Nadu. The breaching activities in Kerala are intense, with a rise of 14% compared with L1.0. Since the beginning of L3.0, a significant rise in breaching activities is observed in every state considered for the analysis. The average rise of 16.9% and 27.6% is observed at the end of L3.0 and L4.0, respectively.
Consistently, the breaching activities in Bihar are noticed to be very high in every lockdown phase while the lowest activities are noticed in Delhi, the capital of India where a substantial difference of 37.5% between the two is observed. Figure 7 presents the mean LBI of considered states computed by considering the day-wise statistics, as shown in Fig. 6a. The intensity of breaching activities in Andhra Pradesh, Rajasthan, Tamil Nadu, and Punjab is almost equal, and the LBI amongst the rest of the states varied significantly, as shown in the table, inset in Fig. 7.
(The numerical values of LBI for all the states is presented in the table inset in Fig. 7)
It is anticipated that there exists a correlation between LBI and the total number of cases. Therefore, an attempt is made to statistically verify this hypothesis. The null hypothesis is that there exists no correlation between LBI and the total number of cumulative cases. In contrast, the alternative hypothesis states that there is a correlation between LBI and the cumulative number of cases.
As per the considered problem, the size of the dataset is 54 (n = 54) which is a large sample dataset because of which we have used test statistic and we considered the level of significance as 0.01
- Null hypothesis:
-
H0 : ρ = 0
- Alternative hypothesis:
-
H1 : ρ > 0
- Level of significance:
-
α = 0.01.
- Critical region:
-
ie rs > 0.317
- Computation: spearman’s correlation coefficient:
-
rs = 0.88
Since the computed Spearman’s correlation coefficient rs = 0.88 lies in the critical region ( rs > 0.317), the null hypothesis is rejected. Also, P value is computed using SPSS SoftwareFootnote 3® and is found to be 0.00001. Therefore, it is affirmed that there exists a correlation between LBI and the cumulative confirmed cases providing an evidence for our hypothesis.
A good correlation between mean LBI of considered states, and cumulative confirmed cases is observed except in the states of Delhi, Maharastra, and Gujarat. The correlation between LBI and total confirmed cases is 0.88, which confirms the strong interrelation between LBI and the number of cases. The relation between cumulative confirmed cases, LBI, and time (days passed since the inception of lockdown) is developed using two mathematical models. Model 1 aids in computing the LBI by considering the time as the independent variable, and model 2 helps to determine the cases by considering the estimated LBI as the independent variable. The developed mathematical models are shown as Eqs. 7 and 8, and the trend is shown in Fig. 8a and b respectively. It has to be noted that since the LBI related to weekends are outliers, as evident from Fig. 6a, they are exempted from modeling the relation between the considered variables. To develop the relationship between the two variables, i.e., “LBI” and “time,” the criterion used is a sigmoidal growth model based on the similar study of Aferni (2020) and Dutra (2020) [18, 19]. Further, we have chosen a specific trend, i.e., Morgan-Mercer-Flodin (MMF) model over other sigmoidal models as it resulted a realistic time frame (223 days since lockdown) for attaining upper asymptote (peak LBI value, i.e., 100). In contrast, unrealistic time frame to attain upper asymptote is observed in other types of sigmoidal models. Therefore, the MMF model, as shown in Eq. 7, is chosen as the best model in context to the current study. Since a good correlation (rs = 0.88) is observed between LBI and cases, a similar model is used to develop the relation between LBI and cases as shown in Eq. 8:
$$ \mathrm{LBI}=\frac{ab+c{\left(\mathrm{days}\right)}^f}{b+{\left(\mathrm{days}\right)}^f}\kern1.00em \left({\mathrm{R}}^2=0.95\right) $$
(7)
where a = 52 (LBI at time t = 0, i.e., on the day of lockdown); b = 14.48 × 107 (parameter that governs point of inflection); c = 100 (upper asymptote, i.e., max possible value of LBI); f = 3.86 (growth rate); days = total number of days since the inception of lockdown
$$ \mathrm{cases}=\frac{pq+r{\left(\mathrm{LBI}\right)}^s}{q+{\left(\mathrm{LBI}\right)}^s}\kern1.00em \left({\mathrm{R}}^2=0.92\right) $$
(8)
where p < 0 (since the cumulative number of cases on the day just before lockdown cannot be negative, it can be treated as 0 which is justifiable); b = 2.8 × 102 (parameter that governs point of inflection); r = 375.2 (Upper asymptote of cases in hundreds on the day when LBI reaches a maximum, i.e., 100); s = 0.89 (growth rate), and LBI is lockdown breaching index.
Though the correlation between LBI and cases is evident from the Spearman’s rank correlation as discussed above, the rate at which cases will increase with the rise in LBI remains unmapped, and hence, Eqs. 7 and 8 are estimated. It has to be noted that due to lack of information regarding the upper asymptote, it is considered that the lockdown (all restrictions) will be lifted after November 1, 2020; thereby, it is expected that LBI reaches to a maximum of 100 on November 1, 2020. Deviation in this based on the policies of Indian Government, the estimated coefficients are expected to vary. However, the developed relations will help to analyze if people are cautious. The coefficients of Eq. 8 are also expected to vary as the dataset is varying dynamically.