Appendix A. MATLAB Simulation Example: Three Cases of a Ph.D. Student’s Financial Status with the Proposed Static and Dynamic Strategic Approaches
%% StaticFiscalModel_case1to3.m
%% Evaluation of Annual Fiscal Increasing Rate
clear all; close all; clc;
format compact; warning off; fontsize = 10;
tic;
%% Case I: Budget of 0.5FTE Graduate Assistant (GA, either TA or RA) annual salary
A0 = 18000;
ax0 = A0/26; % Payroll Period for one calendar year (365/14 = 26)
wt1 = 0.60; wt2 = 0.25; wt3 = 0.10; % Weights of depositing saving accounts
n1 = 1.00/100; % Saving Account I (CIT/Barclay) annual percentage interest (current API)
n2 = 0.90/100; % Saving Account II (Ally Bank/Discover) API (on average of the past 2 years)
n3 = 0.75/100; % Saving Account III (Capital One 360/Bank of Interest) (current API)
ax1 = zeros(1,12); ax2 = zeros(1,12); ax3 = zeros(1,12); % Initialization (a indicates case I)
for i = 1:12 % Online-saving automatically deposits monthly interests, calculating interests if fully deposits into one single saving account
ax1(i) = ax0*(2*i)*(n1/12); % Assume monthly interest deposited at the end of each month
ax2(i) = ax0*(2*i)*(n2/12);
ax3(i) = ax0*(2*i)*(n3/12);
end
y1 = (A0+sum(ax1))*wt1 + (A0+sum(ax2))*wt2 + (A0+sum(ax3))*wt3 + A0*(1-wt1-wt2-wt3);
% Account credit after annual (12-month) saving;
rate1 = 0.05; % Annual average yield rate from investment in Saving I, considered as 5%
rate2 = 0.03; % Annual mortgage rate in Saving II, considered as 3%
bonus = 200; % Bonus credit from opening all new accounts (annual, on average)
exped_a = 1000;
cred_score1 = (exped_a/3)*2.0*12; % Conservative estimation for all accumulated credit scores
% (Assume 1/3 expenditures spent towards credit score, count 2.0% on average)
% In fact, quite many credit cards offer 5.0% cash back calender rewards)
% Practically annual accumulated credit score has been estimated as 8000.
gift1 = (cred_score1*0.5/0.9)/100;
% Gift card credit, half of the credit score has been traded into gift_card on sale (10% discount)
online_consumption1 = exped_a*12*0.08; % 5-10% online consumption, counting 8% on average
cashback1 = cred_score1*0.5/100 + 0.01*online_consumption1; % Annual cashback from major credit cards
Y_case1 = y1 + (A0+sum(ax1))*wt1*rate1 + (A0+sum(ax1))*wt2*rate2 + bonus + gift1 + cashback1;
% Estimated end-of-the-year balance
inflation = 0.025;
living_cost = zeros(1,12);
for j = 1:12
living_cost(j) = exped_a*(1 + inflation*(j-1)/12);
% Buying power of the spent cost in presence of 2.5% annual inflation rate
end
Accumulated_living_cost = sum(living_cost);
% $1000 is the remainder GA should grossly pay (deducting GA refund) for two semesters per calender year
Tuition_payments = 500*2;
% $1000 is the remainder GA should grossly pay (deducting GA refund) for two semesters per calender year
Total_expense1 = Accumulated_living_cost + Tuition_payments;
delta1 = Y_case1 - Total_expense1; % Living expenses in presence of annual inflation (2.5% on average)
A0 = A0*(1 + inflation);
AP1 = (A0 - Total_expense1)/A0 * 100;
% The remaining balance without multi-level fiscal modeling in proportion to single direct deposits
AP2 = (delta1 / A0) * 100; % The remaining balance after multi-level fiscal modeling for comparison
AP3 = (Y_case1 - A0)/A0 * 100; % Annual financial increasing rate in presence of modeling
Y_case1
Total_expense1
delta1
AP1
AP2
AP3
%% Case II: Budget of 12-month Quarter TA/RA Annual Gross Salary
unit1 = 450; unit2 = 400;
B0 = unit1*11 + unit2*15; % first $5,000 / $5,800 is tax free due to US-China, US-India treaty
bx0 = B0/26; % Average deposit per payroll period for one calendar year (365/14 = 26)
wt1 = 0.60; wt2 = 0.25; wt3 = 0.10; % Weights of depositing saving accounts
n1 = 1.00/100; % Saving Account I (CIT/Barclay) annual percentage interest (API)
n2 = 0.90/100; % Saving Account II (Ally Bank) API
n3 = 0.75/100; % Saving Account III (ING Direct) API
bx1 = zeros(1,12); bx2 = zeros(1,12); bx3 = zeros(1,12); % Initialization
for i = 1:12 % Online-saving automatically deposits monthly interests, calculating interests if fully deposits into one single saving account
if i <= 5
bx1(i) = unit1*(2*i)*(n1/12); % Assume monthly interest deposited at the end of each month
bx2(i) = unit1*(2*i)*(n2/12);
bx3(i) = unit1*(2*i)*(n3/12);
else
bx1(i) = unit2*(2*i)*(n1/12); % Assume monthly interest deposited at the end of each month
bx2(i) = unit2*(2*i)*(n2/12);
bx3(i) = unit2*(2*i)*(n3/12);
end
end
y2 = (B0+sum(bx1))*wt1 + (B0+sum(bx2))*wt2 + (B0+sum(bx3))*wt3 + B0*(1-wt1-wt2-wt3);
% Account credit after annual (12-month) saving;
rate1 = 0.05; % Annual average yield rate from investment in Saving I, considered as 5%
rate2 = 0.03; % Annual mortgage rate in Saving II, considered as 3%
bonus = 200; % Bonus credit from opening all new accounts (annual, on average)
exped_bc = 800;
cred_score2 = (exped_bc*0.5)*2.0*12;
% Conservative estimation for all accumulated credit scores (Assume 1.5% cash back on average)
gift2 = (cred_score2*0.5/0.8)/100; % Gift card credit
online_consumption2 = exped_bc*12*0.08; % 5-10% online consumption, counting 8% on average
% Annual cashback from major credit cards
cashback2 = cred_score2*0.5/100 + 0.01*online_consumption2;
Y_case2 = y2 + (B0+sum(bx1))*wt1*rate1 + (B0+sum(bx1))*wt2*rate2 + bonus + gift2 + cashback2;
% Estimated end-year balance
inflation = 0.025;
thrift_living_cost_bc = zeros(1,12);
for j = 1:12
thrift_living_cost_bc(j) = exped_bc*(1 + inflation*(j-1)/12);
% Buying power of the spent cost in presence of 2.5% annual inflation rate
end
Accumulated_thrift_living_cost = sum(thrift_living_cost_bc);
Tuition_payments = 500*2;
% $1000 is the remainder GA should grossly pay (deducting GA refund) for two semesters per calender year
Total_expense2 = Accumulated_thrift_living_cost + Tuition_payments;
delta2 = Y_case2 - Total_expense2; % Living expenses in presence of annual inflation (2.5% on average)
B0 = B0*(1 + inflation); % Estimating the dynamic buying power (in presence of 2.5% annual inflation;
% e.g., the buying power of $10,000 at the end of last year, is equal to $10,250 at the end of current year)
BP1 = (B0 - Total_expense2)/B0 * 100;
% The remaining balance without multi-level fiscal modeling in proportion to single direct deposits
BP2 = (delta2 / B0) * 100; % The remaining balance after multi-level fiscal modeling for comparison
BP3 = (Y_case2 - B0)/B0 * 100; % Annual financial increasing rate in presence of modeling
toc;
Y_case2
Total_expense2
delta2
BP1
BP2
BP3
%% Case III: Self-support (coming from parental support)
L0 = 2*10^6 * 0.05;
C0 = L0/6.25;
% Relying on a financial product (5% annual interest) of main investment, divided by the currency rate
% Half of the interest benefits pay the tuition and medical insurance, the other half pays the living expenses
cx0 = C0*0.6/12; % Unit of monthly expenditures (60% on living expenses)
wt1 = 0.60;
wt2 = 0.25; wt3 = 0.10; % Weights of depositing saving accounts
n1 = 1.00/100; % Saving Account I (CIT/Barclay) annual percentage interest (API)
n2 = 0.90/100; % Saving Account II (Ally Bank) API
n3 = 0.75/100; % Saving Account III (ING Direct) API
cx1 = zeros(1,12); cx2 = zeros(1,12); cx3 = zeros(1,12); % Initialization
for i = 1:12 % Estimating how much remaining funds participating in the calculation of interests
cx1(i) = (C0 - cx0*i) * (n1/12); % Compound Interest added, if fully depositing into Saving Account I
cx2(i) = (C0 - cx0*i) * (n2/12); % Similarly for Saving Account II
cx3(i) = (C0 - cx0*i) * (n3/12); % Similarly for Saving Account III
end
y3 = (C0+sum(cx1))*wt1 + (C0+sum(cx2))*wt2 + (C0+sum(cx3))*wt3 + C0*(1-wt1-wt2-wt3);
% Account credit after annual (12-month) saving;
rate1 = 0.05; % Annual average yield rate from investment in Saving I, considered as 5%
rate2 = 0.03; % Annual mortgage rate in Saving II, considered as 3%
bonus = 200; % Bonus credit from opening all new accounts (annual, on average)
tutorial_unit = 16*2;
tutorial_allowance = tutorial_unit * 15 * 2; % Two semesters of allowance in Sunday Chinese school
exped_bc = 800;
cred_score3 = (exped_bc*0.5)*2.0*12;
% Conservative estimation for all accumulated credit scores (Assume 1.5% cash back on average)
gift3 = (cred_score3*0.5/0.8)/100; % Gift card credit
online_consumption3 = exped_bc*12*0.08; % 5-10% online consumption, counting 8% on average
cashback = cred_score3*0.5/100 + 0.01*online_consumption3; % Annual cashback from major credit cards
Y_case3 = y3 + (C0+sum(cx1))*wt1*rate1 + (C0+sum(cx2))*wt2*rate2...
+ bonus + gift3 + cashback + tutorial_allowance; % Estimated end-year balance
thrift_living_cost_bc = zeros(1,12);
inflation = 0.025;
for j = 1:12
thrift_living_cost_bc(j) = exped_bc*(1 + inflation*(j-1)/12);
% Buying power of the spent cost in presence of 2.5% annual inflation rate
end
Accumulated_thrift_living_cost = sum(thrift_living_cost_bc);
Tuition_payments = 1787 + 2333 + 100 * 2;
% Tuition and medical payments of Fall’14 and Spring’15, plus international student fee $100*2
Total_expense3 = Accumulated_thrift_living_cost + Tuition_payments;
% Annually expenditure in 2014-2015
delta3 = Y_case3 - Total_expense3; % Living expenses in presence of annual inflation (2.5% on average)
C0 = C0*(1 + inflation)+ tutorial_allowance; % Estimate the dynamic buying power in presence of 2.5% annual inflation; note: allowance is considered of 0% interest, into checking
% e.g., the buying power of $10,000 at the end of last year, should be considered as $10,250 at the end of current year)
CP1 = (C0 - Total_expense3)/C0 * 100;
% The percentage of remaining balance to annual expenditures without multi-level fiscal modeling
% in proportion to original deposits coming from parental support
CP2 = (Y_case3 - Total_expense3)/C0 * 100; % The remaining balance after multi-level fiscal modeling for comparison % Note: CP2 = delta3 /A0 * 100; identical
CP3 = (Y_case3 - C0)/C0 * 100;
% Difference with / without multi-level fiscal modeling (also known as the percentage increment)
Y_case3
Total_expense3
delta3
CP1
CP2
CP3
toc;
% Y_case1 = 1.9053e+04
% Total_expense1 = 13138
% delta1 = 5.9159e+03
%
% AP1 = 28.7940
% AP2 = 32.0646
% AP3 = 3.2706
% Y_case2 = 1.1726e+04
% Total_expense2 = 10710
% delta2 = 1.0162e+03
%
% BP1 = 4.5773
% BP2 = 9.0543
% BP3 = 4.4769
% Y_case3 = 1.8195e+04
% Total_expense3 = 14030
% delta3 = 4.1655e+03
%
% CP1 = 19.1820
% CP2 = 22.7353
% CP3 = 3.5533
%% Calculation of Average US Annual Inflation based on monthly statistics (2012-Present)
%% Load the Inflation rates (2012-Present)
Y2012 = [2.93 2.87 2.65 2.30 1.70 1.66 1.41 1.69 1.99 2.16 1.76 1.74];
Y2013 = [1.59 1.98 1.47 1.06 1.36 1.75 1.96 1.52 1.18 0.96 1.24 1.50];
Y2014 = [1.58 1.13 1.51 1.95 2.13 2.07 1.99 1.70 1.66 1.66 1.32 0.76];
Y2015 = [-0.09 -0.03 -0.07 -0.20 -0.04 0.12 0.17 0.20 -0.04 0.17 0.50 0.73];
Y2016 = [1.37 1.02 0.85 1.13 1.02 1.00 0.83 1.06 1.46 1.64 1.69 2.07];
Y2017 = [2.50 2.74 2.38 2.20 1.87 1.63 1.73 1.94 2.23 2.04 2.20 2.11];
Y2018 = [2.07 2.21 2.36 2.46 2.80 2.87 2.95 2.70 2.28 2.52 2.18 1.91];
Y2019 = [1.55 1.52 1.86 2.00 1.79 1.65 1.81 1.75 1.71 1.76 2.05 2.29];
Y2020 = [2.49 2.33 1.54 0.33 0.12 0.65 0.99 1.31 1.37 1.18 1.17 1.36];
Y2021 = [1.40 1.68 2.62 4.16 4.99 5.39 5.37 5.25 5.39 6.22 6.81 7.04];
Y2022 = [7.48 7.87 8.54 8.56 8.28 9.06 8.52 8.26 8.20 7.75 7.11 6.45];
Y2023 = [6.41 6.04 4.98 4.93 4.05 2.97 3.18 3.67 3.70 3.24 3.14 3.35 ];
%% Firstly, compute the 12-month mean and std of US inflation rate in the past ten years
% Note: mean and std for Year 2023 are 10-month based statistics
data_mean = [mean(Y2012) mean(Y2013) mean(Y2014) mean(Y2015) mean(Y2016)...
mean(Y2017) mean(Y2018) mean(Y2019) mean(Y2020) mean(Y2021) mean(Y2022)]; % mean(Y2023)
data_std = [std(Y2012) std(Y2013) std(Y2014) std(Y2015) std(Y2016)...
std(Y2017) std(Y2018) std(Y2019) std(Y2020) std(Y2021) std(Y2022) ]; % std(Y2023)
%% Choose color with respect to individual demands
RGB2 = cbrewer2(‘seq’, ‘Blues’, 12, ‘linear’);
RGB = [RGB2(5,:)]; % Define the color of bars
%% Plot the curves
figure();
y = data_mean;
neg = data_std;
pos = data_std;
n = size(y,2);
n0 = 2012;
nk = 2012 + n - 1;
x = n0:1:nk;
h = bar(x,y);
hold on; grid on; grid on;
%% Set up the color of j-th bar separately
for j = 1:(n-1)
h.FaceColor = ‘flat’;
h.CData(j,:) = RGB(j,:);
h.EdgeColor = ‘flat’;
end
%% Acquire the x-value of error bars
xx = h.XEndPoints;
% Plot the error curves
hold on; grid on; grid on;
errorbar(xx, y, neg, pos, ‘LineStyle’, ‘none’, ‘Color’, ‘k’, ‘LineWidth’, 1);
hold off;
%% Set up the format of figure (default fontsize = 8, fontstyle = Arial)
set(gca, ‘FontSize’, 12);
set(gca,’FontName’,’Times New Roman’);
% Set up xticklabels at x-axis
set(gca, ‘XTickLabel’, {‘\fontname{Times New Roman}Con1’, ‘\fontname{Times New Roman}Con2’, ...
‘\fontname{Times New Roman}Con3’},’FontSize’,12);
% Set up the tags of y-axis
ylabel(‘\fontname{Times New Roman}y\fontname{Times New Roman}Average Inflation Rate’,’FontSize’,14);
% Set up the range of y-axis
ylim([0 10]);
% Remove upper boundary and right boundary
box off
% Set up the thickness of frames
set(gca,’XColor’,’k’,’YColor’,’k’,’linewidth’,1);
%% Predict the annual growth rate of appreciation on saving net assets
%% with respect to jointly combine static and dynamic strategic approaches
%% via Arbitrage silver dollars, Arbitrage 2-pt RMB-USD Exchange rate,
%% Zero-risk Online Savings or 1-year CD, Cash back and Gift Credits (M3)
%% By Xin Gao et al, Jiangsu Normal University, Xuzhou, Jiangsu, China, Nov. 2023
clear all; close all; format compact; fontsize = 10; warning off;
tic;
%% Step 1. Compute the annual net assets after each deduction as discussed above,
%% and initial this amount as M0.
Gross_Income = 150000; % Median of annual gross-income of middle-class family
Month_Income = Gross_Income/12;
Tax_Paying = Month_Income * 0.37; % Highest tax-rate is 37%
Avg_Month_Expense = 3075; % Estimated with State of highest cost, i.e.,Hawaii
Month_Net_Assets = (Month_Income - Tax_Paying - Avg_Month_Expense);
Annual_Net_Assets = Month_Net_Assets*12;
%% Step 2.Apply Dynamic Strategic Approaches: APT Silver Dollar and Currency Exchange Rates
APT_Silver_Dollar = Month_Net_Assets*0.10*0.25*12; % 10% of Net Assets
APT_Currency_Rate = 50000*2/100; % Upper limit of $50,000 per year in China
Current_Rate = 4.35/100; % Current API of Citi Online Banking
CD_Rate = 5.25/100; % Current CD_rate (highest 5.50% minus 25 percentage points)
Deducted_rate = 4.35 - 0.25*3; % Assume Federal Bureau reduce API 0.25% three times
%% Steps 3-4.Reapply Static Fiscal Modeling, calculating interests from online saving or 1-year CD
Saving_API = Annual_Net_Assets*0.80*Current_Rate;
Saving_CD = Annual_Net_Assets*0.80*CD_Rate; % Assume Conducting 1-year CD
Saving_API_deduction = Annual_Net_Assets*0.80*Deducted_rate/100; % Reduced Saving bonus
Avg_Cash_Rate = 0.02; % Most consumption with Citi double-cash reward card
% Others ranging from 1% to monthly 5% bonus cashback
Annual_Cash_Back = Avg_Month_Expense*12*Avg_Cash_Rate;
Delta_Gift_Reward = 5; % Average 5 bucks per month estimated for gift reward
Annual_Gift_Money = Delta_Gift_Reward*12;
M0 = Annual_Net_Assets;
Delta_M0 = APT_Silver_Dollar + APT_Currency_Rate;
Delta_M1 = Annual_Cash_Back + Annual_Gift_Money;
Delta_M2_A = Saving_API;
Delta_M2_B = Saving_CD;
Delta_M2_C = Saving_API_deduction;
%% Step 5. Calculate the appreciation of net assets in broad money (M3),
%% and compute the percentage of appreciation in three cases.
Delta_M3_A = Delta_M0 + Delta_M1 + Delta_M2_A;
Delta_M3_B = Delta_M0 + Delta_M1 + Delta_M2_B;
Delta_M3_C = Delta_M0 + Delta_M1 + Delta_M2_C;
Percent_Diff_A = 100*Delta_M3_A/M0;
Percent_Diff_B = 100*Delta_M3_B/M0;
Percent_Diff_C = 100*Delta_M3_C/M0;
Vector = [Percent_Diff_A Percent_Diff_B Percent_Diff_C]’;
Vector
toc;
>> Dynamic_Static_Asset_Pred
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