In: Economics
a. Obtain the linear trend equation for the
following data on new checking accounts at Fair Savings Bank and
use it to predict expected new checking accounts for periods 16
through 19. (Round your intermediate calculations and final
answers to 2 decimal places.)
Period | New Accounts | Period | New Accounts | Period | New Accounts |
1 | 200 | 6 | 239 | 11 | 281 |
2 | 215 | 7 | 246 | 12 | 275 |
3 | 211 | 8 | 250 | 13 | 283 |
4 | 229 | 9 | 256 | 14 | 288 |
5 | 235 | 10 | 267 | 15 | 319 |
b.Use trend-adjusted smoothing with α = .2 and β =
.1 to smooth the new account data in part a. What is the forecast
for period 16? Compute the initial trend estimate (Tt)
for Period 5 as follows: (Period 4 data – Period 1 data) / 3. Then
compute the initial trend-adjusted forecast (TAFt) for
Period 5 as follows: Period 4 data + Initial trend estimate for
Period 5. Then compute all remaining values (including the
St value for Period 5) using the textbook formulas or
Excel template. (Round the "Trend"values (Tt) to 3 decimal
places and all other intermediate forecast values (TAFt and St) to
2 decimal places. Round your final answer to 2 decimal
places.)
a.
Linear trendline equation:
y = a+bx
where, a is the intercept, x = time period, b is the slope and y is the new period
Hence, the linear trendline equation :
y = 195.25 + 7.21x
The expected values are :
For, y =
16 == 310.62
17 == 317.83
18 == 325.04
19 == 332.25
b.
Initial trend(Tt) = (Period 4 data - Period 1 data)/3
=(229-200)/3 = 9.667
Initial trena adjusted forecast (TAFt) = Period 4 data + Initial trend estimate for Period 5(St)
TAFt = Tt +St
Calculate all values using:
St = TAFt + 0.2(A-TAFt)
Tt = Tt-1 + 0.1(TAFt - TAFt-1 - Tt-1
Therefore, forecast for period 16 is 361.21