From regression to consolidation accounting — quantitative depth of L2.
The general specification is Y = β₀ + β₁X₁ + β₂X₂ + … + βₖXₖ + ε. Five core assumptions of classical linear regression: (1) linearity, (2) independence of ε, (3) homoskedasticity, (4) normality of ε, (5) no perfect multicollinearity. Violations require diagnostic tests:
| Violation | Test | Correction |
|---|---|---|
| Heteroskedasticity | Breusch-Pagan | White-corrected standard errors |
| Serial correlation | Durbin-Watson | Hansen / Newey-West standard errors |
| Multicollinearity | Variance Inflation Factor > 10 | Drop / combine correlated regressors |
R²adj = 1 − [(n − 1) / (n − k − 1)] × (1 − R²). The F-test of joint significance: F = [R²/k] / [(1 − R²)/(n − k − 1)], compared to Fk, n−k−1, α. Reject H₀ (all β = 0) if F > critical value.
Monthly excess returns of a small-cap fund regressed on (Mkt-Rf), SMB, HML. Output: β₁ = 1.12 (t=8.4), β₂ = 0.65 (t=4.2), β₃ = 0.18 (t=1.1), α = 0.0032 (t=0.9), R² = 0.78, n = 60. Interpret.
Interpretation: Market (Mkt-Rf) and small-cap tilt (SMB) are highly significant. Value loading (HML) and α (manager skill) are not significant at 5%. The fund delivers no alpha after controlling for systematic factors — pure factor exposure.
In a no-arbitrage world, F / S = (1 + rd) / (1 + rf) where F = forward FX rate, S = spot, rd = domestic rate, rf = foreign rate. CIRP is enforced by arbitrageurs; deviations beyond transaction costs imply riskless profit.
Uncovered IRP: E(St+1) / St ≈ (1 + rd) / (1 + rf). Empirically, UIP fails over short horizons (forward premium puzzle). Purchasing Power Parity (PPP) states that exchange rates adjust to equalise the price of a basket of goods: ΔS = πd − πf (relative PPP).
"Empirical research consistently rejects strict PPP in the short run but supports relative PPP over horizons of 5-10 years."
Source: International Monetary Fund Working Paper WP/19/27 — imf.org/en/Publications/WP
| Ownership | Influence | Method (IFRS) | Method (US GAAP) |
|---|---|---|---|
| < 20% | Passive | Fair value through P&L or OCI | FV / Cost |
| 20% - 50% | Significant | Equity method (IAS 28) | Equity method |
| > 50% control | Control | Full consolidation (IFRS 10) | Full consolidation (ASC 810) |
| 50/50 joint control | Joint venture | Equity method (IFRS 11) | Equity method |
When a parent acquires a subsidiary, all identifiable assets and liabilities are remeasured at fair value on the acquisition date. Goodwill = consideration transferred + non-controlling interest (NCI) + fair value of previously held interest − net identifiable assets. Under IFRS, goodwill may be measured at full goodwill (NCI at FV) or partial goodwill (NCI at proportionate share). US GAAP requires full goodwill.
Parent acquires 80% of Sub for €640M cash. Sub net identifiable assets FV = €700M. NCI fair value = €170M.
Full goodwill: 640 + 170 − 700 = €110M. NCI on BS = €170M.
Partial goodwill: 640 + (20% × 700) − 700 = 640 + 140 − 700 = €80M. NCI on BS = €140M.
For a defined benefit plan, the employer reports a net pension liability (asset) = Present Value of Defined Benefit Obligation (DBO) − Fair Value of Plan Assets. Annual changes include service cost, net interest cost (DBO − assets × discount rate), actuarial gains/losses (OCI under IAS 19R, recycled vs not), past service cost, and contributions/benefits paid. Discount rate must be a high-quality corporate bond yield matching the duration of the obligation.
Categorical regressors are encoded as dummy variables (0/1). For k categories, use k-1 dummies to avoid the dummy variable trap (perfect multicollinearity). Example: sector dummies = (Tech, Health, Energy) → 2 dummies (Tech=1 if tech 0 otherwise; Health=1 if health 0 otherwise; Energy is the baseline omitted category).
Multiplying two regressors creates an interaction term. Example: returns regressed on (Beta) + (Quality) + (Beta × Quality) tests whether the effect of beta depends on quality. Coefficient significance on the interaction term confirms or rejects the hypothesis.
When the dependent variable is binary (default vs no-default, M&A success vs failure), use logistic regression: P(Y=1) = 1 / (1 + e−(β₀+β₁X)). Output is a probability, not a continuous prediction.
L2 introduces time series analysis: AR(p), MA(q), ARMA(p,q), ARIMA(p,d,q) and ARCH/GARCH models for volatility. Key concepts:
| Parity | Equation | Assumption | Tested empirically |
|---|---|---|---|
| Covered IRP | F/S = (1+r_d)/(1+r_f) | No arbitrage | Holds (CCP enforced) |
| Uncovered IRP | E(S_t+1)/S = (1+r_d)/(1+r_f) | Risk neutrality | Fails short-term (forward premium puzzle) |
| Absolute PPP | S = P_d / P_f | Single basket equivalence | Rejected (Big Mac index) |
| Relative PPP | ΔS ≈ π_d − π_f | Inflation differential | Holds 5-10y |
| Fisher Effect | r_nominal = r_real + π | Inflation expectations | Holds for IG bonds |
| International Fisher Effect | r_d − r_f = π_d − π_f | Cross-border real rate equality | Holds long-term |
Under IFRS 3 (revised), a step acquisition triggers remeasurement of the previously held interest to fair value with the gain/loss recognised in profit or loss. Example: Parent owned 50% of Sub at carrying value €200M. Acquires additional 30% for €180M cash. FV of 50% original = €260M. Step-up gain = 260 - 200 = €60M recognised in P&L. New goodwill computed on the full 80%.
When a parent loses control (sale of stake reducing to ≤50%), the remaining investment is remeasured to fair value and the difference flows through P&L. The retained stake is then accounted under equity method or fair value method depending on remaining influence.
Acme Pension Plan, FY2025 (€M):
Calculations:
Before fitting an ARMA(p,q), test for stationarity using the Augmented Dickey-Fuller (ADF) test: H₀ = unit root (non-stationary), H₁ = stationary. Reject H₀ if the test statistic is more negative than the critical value. For non-stationary series, take first differences (d=1) until stationary, giving an ARIMA(p,d,q) model.
Once stationary, examine the autocorrelation function (ACF) and partial autocorrelation function (PACF):
| Pattern | Implies |
|---|---|
| ACF tails off, PACF cuts off at lag p | AR(p) |
| ACF cuts off at lag q, PACF tails off | MA(q) |
| Both tail off | ARMA(p,q) — need information criteria |
Two competing models can be ranked by:
Financial returns exhibit volatility clustering (large changes followed by large changes). The GARCH(1,1) model captures this:
σ²t = ω + α × ε²t-1 + β × σ²t-1
where α captures reaction to recent shocks and β captures persistence. Long-run variance = ω/(1−α−β). Typical equity GARCH: α ≈ 0.08, β ≈ 0.90, so α+β ≈ 0.98 (high persistence). Used in option pricing, VaR, and risk management.
An institutional investor borrows JPY at 0.10% to invest in USD-denominated 1-year US Treasuries yielding 4.50%. Spot rate: 145 JPY/USD. 1-year forward: 141.40 JPY/USD (per CIRP).
If UIP holds: Expected JPY appreciation = USD interest rate premium − JPY rate ≈ 4.40% (forward = expected future spot). Net carry profit = 0%.
Empirical reality: UIP often fails over 1-3 year horizons (forward premium puzzle). Yen historically appreciates only ~1-2% vs the 4-4.5% the forward implies. Net carry profit ≈ 2-3% per year — historically positive but with sudden large losses during risk-off episodes (e.g., 2008 GFC, March 2020 COVID, August 2024 yen unwind).
Risk: A 5% sudden JPY appreciation wipes out 2+ years of carry. Position must be sized accordingly.
| Topic | IFRS | US GAAP | Difference impact |
|---|---|---|---|
| Inventory | FIFO or WA only | FIFO, LIFO, WA | LIFO firms have lower NI in inflation |
| LIFO Reserve disclosure | N/A | Required | Adjustment for analyst comparison |
| R&D | Research expensed; development capitalised if criteria met | Both expensed | IFRS capitalisation inflates assets |
| PP&E revaluation | Permitted (IAS 16) | Not permitted | IFRS can show higher equity |
| Component depreciation | Required for significant parts | Permitted | IFRS more granular |
| Intangible amortisation period | Useful life | Useful life | Convergence |
| Goodwill | Annual impairment | Annual impairment | Converged |
| Impairment indicator | One-step (CGU value-in-use) | Two-step (carrying vs FV) | IFRS more frequent write-downs |
| Impairment reversal | Allowed (not goodwill) | Prohibited | IFRS recognises recovery |
| Lease classification (IFRS 16 / ASC 842) | All operating + finance on BS | Same, but separate P&L impact | IFRS single model, GAAP dual |
| Interest paid CFS | Operating or Financing | Operating | Different classification effect |
| Dividends paid CFS | Operating or Financing | Financing | — |
| Dividends received CFS | Operating or Investing | Operating | — |
| Bond issuance costs | Reduction of debt | Reduction of debt (since ASU 2015-03) | Converged |
| Convertible bonds | Bifurcate liability + equity | Single liability (since ASU 2020-06) | IFRS preferable for separability |
| Item | DBO (€M) | Plan Assets (€M) | P&L (€M) | OCI (€M) |
|---|---|---|---|---|
| Opening balance | +850 | +700 | — | — |
| Service cost | +45 | — | −45 | — |
| Interest on DBO @ 4% | +34 | — | −34 | — |
| Interest on assets @ 4% | — | +28 | +28 | — |
| Actuarial loss on DBO | +22 | — | — | −22 |
| Actual return − expected | — | +22.5 | — | +22.5 |
| Contributions | — | +30 | — | — |
| Benefits paid | −28 | −28 | — | — |
| Closing balance | +923 | +752.5 | −51 | +0.5 |
Net pension liability closing = 923 − 752.5 = €170.5M. P&L impact: total expense €51M. OCI impact: net actuarial movement +€0.5M (loss of 22 + gain of 22.5).
Three additional questions follow the in-leçon quiz to reinforce learning.
| Term | Definition |
|---|---|
| ARMA(p,q) | Autoregressive Moving Average model with p lags and q error terms |
| ARCH/GARCH | Models volatility clustering in returns |
| Co-integration | Two non-stationary series with stationary linear combination |
| VIF (Variance Inflation Factor) | Diagnostic for multicollinearity in regression |
| Forward bias | Empirical deviation from UIP enabling carry trade profits |
| DBO (Defined Benefit Obligation) | PV of future pension benefits earned to date |
| NCI (Non-Controlling Interest) | Minority share in subsidiary not owned by parent |
| Step acquisition | Acquiring control in stages with FV remeasurement |
| Bargain purchase | Goodwill is negative — recognised in P&L |
Inscrivez-vous pour accéder aux 5 autres leçons + le quiz final.
Créer mon compteChoisis quels cookies tu acceptes — modifiable à tout moment.