Digital Materials Management & ERP Systems

Chapter 12
Materials Analytics and Managerial Decision-Making

Post Graduate Programme in Materials Management
Digital Materials Management & ERP Systems   •   Post Graduate

Materials Analytics and Managerial Decision-Making

Introduction

Digital materials management has moved beyond recording receipts, issues, purchase orders and stock balances. Modern enterprise resource planning (ERP) systems generate continuous data about demand, inventory, suppliers, warehouses, logistics, quality, finance and customer service. The managerial challenge is not data availability; it is converting data into reliable evidence and timely action.

Materials analytics is the disciplined use of data, statistical methods, operational models and managerial judgement to understand materials performance and improve decisions. It connects operational events—such as a late delivery or a stockout—to financial consequences, including lost contribution, excess working capital, expediting cost and supplier-risk exposure.

Analytics does not replace management. A dashboard may reveal that inventory turns have declined, but it cannot by itself determine whether the cause is weak demand, deliberate safety stock, obsolete material, inaccurate bills of material or a strategic supply decision. Effective decision-making therefore combines data quality, appropriate metrics, causal diagnosis, forecasting, optimization and governance.

Learning Objectives

After completing this chapter, the learner should be able to:

  1. Explain the role and hierarchy of diagnostic, predictive and prescriptive analytics in materials management.
  2. Develop meaningful KPIs for inventory, procurement, suppliers, warehouses and working capital.
  3. Design dashboards that distinguish strategic, tactical and operational decisions.
  4. Apply inventory, forecasting and supplier-performance measures correctly.
  5. Interpret analytical results and identify likely root causes rather than merely describing symptoms.
  6. Evaluate the use of ERP, business-intelligence and artificial-intelligence tools in materials decisions.
  7. Recognize data, ethical, organizational and governance risks in materials analytics.

1. The Analytical Architecture of Materials Management

A useful analytical architecture has four layers.

Transaction layer. This contains operational records: purchase requisitions, purchase orders, goods receipts, inspection results, inventory movements, invoices, stock counts, production orders, sales orders and shipment events. ERP modules such as materials management, production planning, sales and distribution, quality management and finance contribute to this layer.

Information layer. Transaction data is cleaned, standardized and integrated. Master data includes material codes, units of measure, lead times, supplier identifiers, warehouse locations, currencies, payment terms, planning parameters and bills of material. A data warehouse or lake may preserve historical snapshots that transactional ERP tables do not retain conveniently.

Analytical layer. This layer calculates KPIs, identifies patterns, estimates future outcomes and evaluates alternative decisions. It includes descriptive, diagnostic, predictive and prescriptive analytics.

Decision and execution layer. Insights become actions: revising reorder points, reallocating stock, changing supplier allocation, releasing a purchase order, escalating a quality issue or discontinuing an obsolete item. The decision should be traceable to an owner, due date and subsequent outcome.

A central principle is decision relevance. A KPI is useful only when its definition is clear, its data is sufficiently reliable, its result can influence an action and the action has an accountable owner.

1.1 Four forms of analytics

Form of analyticsMain questionTypical materials application
DescriptiveWhat happened?Monthly inventory value and service level
DiagnosticWhy did it happen?Decomposing stockout causes
PredictiveWhat is likely to happen?Forecasting demand or late delivery
PrescriptiveWhat should be done?Optimizing order quantity or supplier allocation

Descriptive analytics summarizes historical or current performance. Diagnostic analytics uses segmentation, drill-down, variance analysis and causal investigation. Predictive analytics estimates a future value or probability, while prescriptive analytics compares feasible actions under constraints. These categories overlap in practice: a replenishment recommendation may use historical data, a demand forecast, a supplier-risk model and an optimization routine.

2. KPI Design: From Strategy to Measurement

A key performance indicator should translate a strategic objective into an observable measure. The design process is more important than producing a large number of metrics.

A robust KPI specification includes:

  • name and managerial purpose;
  • precise numerator, denominator and inclusion rules;
  • data source and refresh frequency;
  • organizational scope and time window;
  • owner and target;
  • segmentation dimensions, such as plant, supplier, category or criticality;
  • known limitations and action thresholds.

2.1 The hierarchy of objectives

Materials objectives commonly include:

  • continuity of supply;
  • acceptable customer and production service;
  • low total acquisition and logistics cost;
  • efficient use of working capital;
  • supplier quality and resilience;
  • warehouse productivity and safety;
  • compliance, sustainability and ethical sourcing.

Metrics must be balanced. Measuring only inventory reduction can encourage stockouts. Measuring only purchase-price variance can encourage buyers to select low-priced but unreliable suppliers. A balanced performance system combines service, cost, cash, quality, risk and sustainability measures.

2.2 Inventory KPIs

Inventory turnover measures how many times average inventory is consumed during a period:

Inventory turnover = Cost of goods sold ÷ Average inventory at cost

Here, cost of goods sold and inventory are measured in the same currency and cover the same period. Average inventory is often approximated as (Opening inventory + Closing inventory) ÷ 2, although monthly or daily averages are preferable when inventory fluctuates substantially. Turnover is not meaningful when sales value is used in the numerator and cost value in the denominator.

Days inventory outstanding (DIO) expresses the same relationship in days:

DIO = Average inventory at cost ÷ Cost of goods sold × Number of days in the period

The number of days must correspond to the period—for example, 365 for an annual measure. High turnover may indicate efficiency, but it can also indicate understocking; low turnover may reflect strategic buffers, long purchase cycles or obsolete stock.

Service level has several definitions. Cycle service level is the probability of not experiencing a stockout during a replenishment cycle. Fill rate is the proportion of demand supplied immediately from available stock:

Fill rate = Units supplied immediately ÷ Total units demanded × 100

These measures are not interchangeable. A high cycle service level can coexist with a lower fill rate when occasional stockouts are large. Every organization must specify whether demand is measured by units, order lines, sales orders or production requirements.

Inventory accuracy may be measured as:

Inventory accuracy = Correct counted records ÷ Records tested × 100

The definition of “correct” must include an approved tolerance, because minor quantity differences may be treated differently from a zero balance recorded as available stock.

Obsolescence rate can be expressed as the value of obsolete inventory divided by total inventory value. The policy must define obsolescence using age, engineering discontinuation, demand inactivity or recoverable-value assessment. Age alone is not proof of obsolescence.

2.3 Procurement and supplier KPIs

On-time delivery (OTD) is commonly calculated as deliveries received on or before the agreed date divided by deliveries due. The agreed date must be identified: original promise date, latest confirmed date or required date. Changing the promise date after delay conceals performance deterioration.

Supplier lead-time variability is often described using the standard deviation of observed lead times. For observations L1, L2, ..., Ln, the sample standard deviation is:

sL = √[∑(Li − L̄)² ÷ (n − 1)]

where L̄ is average lead time, n is the number of observations, and the unit is time. This sample formula assumes observations are reasonably comparable and is more appropriate than treating a small sample as the entire population.

Purchase price variance (PPV) for a quantity purchased can be represented as:

PPV = (Actual price − Standard price) × Actual quantity purchased

The sign convention must be stated. Under this convention, a positive value means actual price exceeded standard price. PPV is an accounting or control measure, not a complete measure of procurement value; it excludes quality, freight, payment terms, risk and total cost of ownership.

Supplier defect rate can be based on defective units, rejected lots or defects per million opportunities. The denominator must match the chosen unit. A supplier with small, frequent deliveries should not be compared uncritically with a supplier delivering large, infrequent lots.

2.4 Warehouse KPIs

Important warehouse indicators include order-line picking accuracy, dock-to-stock time, receiving productivity, space utilization, inventory travel distance, cycle-count completion and safety incidents. Productivity measures should be risk-adjusted: a rushed receiving process that increases quality errors is not genuinely productive.

Space utilization is often calculated as occupied usable storage volume divided by available usable storage volume. It should not be confused with building occupancy. Very high utilization may reduce accessibility, increase congestion and weaken resilience during demand surges.

2.5 Working-capital KPIs

The cash conversion cycle links materials decisions to finance:

Cash conversion cycle = DIO + Days sales outstanding − Days payables outstanding

DIO measures time cash is tied in inventory, days sales outstanding measures the time required to collect receivables, and days payables outstanding measures the time taken to pay suppliers. The identity is an analytical approximation and should be calculated using consistent accounting periods and definitions. Extending payment terms may improve the buyer’s cash position but can harm supplier liquidity and resilience.

The value of inventory released by a reduction in average inventory is approximately:

Cash released ≈ Reduction in average inventory value

This is not automatically equal to profit. It represents funds no longer tied up in inventory, subject to tax, liquidation, service and accounting effects.

3. Dashboard Design and Information Hierarchy

A dashboard is a decision interface, not a decorative collection of charts. Its design should begin with decisions and users.

Strategic dashboard

Senior managers need trends and trade-offs: inventory value, cash conversion cycle, service level, supplier concentration, critical shortages, obsolescence exposure, total procurement savings, sustainability and risk. Strategic dashboards normally use monthly or quarterly trends and compare performance with targets, budget and prior periods.

Tactical dashboard

Category managers, planners and procurement leaders need supplier performance, forecast accuracy, inventory segmentation, purchase-price trends, open-order risk, excess-and-obsolete stock and capacity constraints. Weekly review is often appropriate.

Operational dashboard

Planners, buyers and warehouse supervisors need exception queues: shortages within the planning horizon, overdue purchase orders, receipts awaiting inspection, negative stock, blocked invoices, count discrepancies and urgent replenishment signals. Operational dashboards should support immediate workflow, not merely display historical charts.

A good dashboard follows a visual hierarchy:

  1. headline indicators and threshold breaches;
  2. trend and target comparison;
  3. segmentation by plant, category, supplier or material criticality;
  4. drill-down to transactions;
  5. assigned action and status.

Traffic-light colours require governance. A red indicator should have a documented threshold, not an arbitrary visual judgement. Dashboards should show numerator, denominator, date of refresh and data completeness. Users must be able to distinguish a genuine improvement from a missing-data problem.

4. Diagnostic Analytics: Finding the Cause

A KPI describes a condition; diagnosis explains it. Managers should avoid confusing correlation with causation. For example, a stockout may coincide with a forecast error, but the immediate cause may be a blocked invoice, an incorrect unit conversion or an unconfirmed purchase order.

Useful diagnostic methods include:

  • Pareto analysis: rank shortages, defects or spend categories to identify concentration;
  • variance decomposition: separate volume, price, mix, timing and exchange-rate effects;
  • cohort analysis: compare materials or suppliers introduced in different periods;
  • control charts: distinguish common-cause variation from unusual events;
  • root-cause analysis: use process mapping, the five-whys method or a fishbone structure;
  • drill-through analysis: trace a KPI from enterprise level to plant, supplier, material and transaction;
  • segmentation: compare ABC value classes with XYZ demand variability, criticality and supply risk.

ABC analysis commonly ranks items by annual usage value:

Annual usage value = Annual demand quantity × Unit cost

The classification boundaries—such as cumulative percentage bands—are managerial conventions, not universal laws. XYZ classification may use demand variability, but the chosen measure and data window must be disclosed. A high-value, predictable item and a low-value, highly critical item may require equally strong controls for different reasons.

A useful diagnostic sequence is:

  1. Validate the KPI definition and data quality.
  2. Establish the size, duration and location of the deviation.
  3. Segment by material, supplier, site, process and time.
  4. Compare with operational events and policy changes.
  5. Test competing explanations.
  6. Assign corrective action and monitor whether the cause recurs.

5. Predictive Analytics for Materials Decisions

5.1 Demand forecasting

A simple moving average for the next period is:

Ft+1 = (Dt + Dt−1 + ... + Dt−k+1) ÷ k

where Dt is demand in period t, k is the number of periods, and Ft+1 is the forecast. It assumes recent observations are reasonably representative and gives equal weight to the selected periods.

Exponential smoothing gives greater weight to recent demand:

Ft+1 = αDt + (1 − α)Ft

where 0 < α ≤ 1. A high α responds rapidly to changes but may be noisy; a low value is smoother but slower to recognize a shift. These methods do not automatically handle seasonality, promotions, intermittent demand or structural breaks.

Forecast accuracy should not be judged by one metric alone. Mean absolute error is:

MAE = ∑|Dt − Ft| ÷ n

It has the same unit as demand. Mean absolute percentage error is:

MAPE = [∑(|Dt − Ft| ÷ |Dt|) ÷ n] × 100

MAPE is problematic when actual demand is zero or very small. Bias should also be monitored, because a forecast can have acceptable average error while consistently overforecasting or underforecasting.

5.2 Reorder points and safety stock

Under a simple continuous-review model with independent demand and lead-time uncertainty, reorder point can be represented as:

ROP = μd μL + z√(μL σd² + μd² σL²)

where μd is mean demand per unit time, μL is mean lead time, σd is the standard deviation of demand per unit time, σL is the standard deviation of lead time, and z is the standard-normal service factor. The first term is expected demand during lead time; the second is safety stock.

This expression assumes demand and lead time are independent, approximately normally distributed in the relevant aggregate, and measured in compatible units. If demand and lead time are correlated, an additional covariance term is required; if demand is intermittent or lead time is highly skewed, simulation or empirical quantiles may be more appropriate. A commonly used special case with constant lead time is:

ROP = μd L + zσd√L

where L is constant lead time.

The service factor is not a universal policy choice. Increasing z raises protection and inventory, but the value of additional service depends on shortage cost, material criticality and customer consequences.

5.3 Predicting supplier and inventory risk

Predictive models may estimate the probability of late delivery, quality failure, stockout or obsolescence. Features can include historical lead-time variance, confirmation behaviour, order changes, capacity signals, quality records, financial indicators and external risk data. A probability is useful only when calibrated and connected to an intervention. A model that labels a supplier “high risk” without explaining evidence, confidence or available actions is operationally weak and potentially unfair.

6. Prescriptive Analytics and Decision Optimization

Prescriptive analytics evaluates alternatives subject to constraints. Typical decisions include order quantity, reorder timing, allocation among suppliers, warehouse assignment, transport mode and inventory positioning.

A simplified order-quantity model balances ordering and holding costs:

Q* = √(2DS ÷ H)

where D is annual demand in units, S is ordering cost per order, H is annual holding cost per unit, and Q* is the economic order quantity. The model assumes relatively stable demand, constant ordering and holding costs, instantaneous replenishment, no quantity discounts and no stockout or capacity constraints. It is a benchmark, not an automatic ERP recommendation.

A broader optimization model may minimize:

Total cost = Purchase cost + Ordering cost + Holding cost + Transport cost + Shortage cost + Risk cost

The terms must be defined consistently and should not double-count costs. Constraints may include supplier capacity, minimum order quantities, budget, warehouse capacity, shelf life, quality approval, production feasibility and service requirements.

Optimization is not synonymous with mathematical sophistication. A feasible, transparent model with reliable inputs is more valuable than a complex model based on poor master data. Scenario analysis is particularly useful: managers can compare a low-cost scenario, a resilience scenario, a service-maximizing scenario and a carbon-reduction scenario.

7. Worked Application: Inventory and Supplier Dashboard

Consider an illustrative manufacturer with annual cost of goods sold of $24 million. Opening inventory is $5.0 million and closing inventory is $7.0 million. During the year, 1,200 purchase-order lines were due and 1,080 arrived on or before the agreed original date. The business supplied 96,000 of 100,000 demanded units immediately.

Average inventory is:

(5.0 + 7.0) ÷ 2 = $6.0 million

Inventory turnover is:

$24.0 million ÷ $6.0 million = 4.0 turns

DIO is:

$6.0 million ÷ $24.0 million × 365 = 91.25 days

Supplier OTD is:

1,080 ÷ 1,200 × 100 = 90%

Fill rate is:

96,000 ÷ 100,000 × 100 = 96%

Management should not conclude simply that inventory is “too high.” The dashboard should next segment the $2 million increase in closing inventory. Suppose analysis finds $1.2 million in deliberate safety stock for a new product, $0.5 million in slow-moving items caused by a forecast bias, and $0.3 million in material blocked by quality inspection. The appropriate actions differ:

  • validate whether the new-product buffer remains justified;
  • correct the forecast and establish a disposition plan for slow-moving stock;
  • remove the inspection bottleneck and review supplier quality;
  • retain service-level monitoring while reducing avoidable inventory.

The case demonstrates why a single turnover KPI cannot determine the managerial response. The same increase in inventory can represent prudent risk protection, planning failure or process obstruction.

8. Detailed Illustrative Case: Orion Components

Background

Orion Components, a fictional industrial-equipment manufacturer, operates three plants using a common ERP system. Its finance team reports rising inventory value, while production reports frequent shortages of electronic control modules. Procurement claims that supplier prices have fallen, and warehouse managers report increasing congestion.

Problem

The executive dashboard shows inventory turnover declining from 6.2 to 4.8 turns, service level falling from 97% to 93%, and purchase-price variance improving by 3%. These apparently conflicting results create disagreement about whether procurement or planning is responsible.

Analysis

A cross-functional analytical team first validates definitions. The previous OTD KPI used the latest confirmed date rather than the original required date, so supplier punctuality had been overstated. The team then segments inventory by ABC value, demand variability, criticality and status. It discovers:

  1. two high-value modules have highly variable demand and long supplier lead times;
  2. 18% of inventory value is held in materials with no demand for twelve months;
  3. 7% of receipts remain in quality inspection beyond the internal target;
  4. several material master records use inconsistent units of measure;
  5. procurement’s price improvement came partly from a lower-priced supplier whose defect rate doubled;
  6. planners manually override ERP reorder parameters without recording rationale.

A diagnostic review of stockouts shows that 45% arose from late deliveries, 30% from incorrect units of measure or master data, 15% from forecast bias and 10% from inspection delays. The percentages are useful for prioritization, but they do not prove that each factor is independently causal; process confirmation is required.

Approach and solution

Orion implements a governed dashboard with original-date OTD, supplier defect rate, fill rate, inventory status, forecast bias, inspection ageing and cash tied in excess stock. It introduces a criticality-based service policy rather than one blanket service target. For the two strategic modules, it approves dual sourcing and a calibrated safety-stock policy. For obsolete inventory, engineering, sales and finance jointly determine reuse, return, rework or disposal.

Master-data stewardship is assigned to named owners. Unit-of-measure conversions require approval, and manual planning overrides require a reason code and expiry date. A predictive model flags purchase orders with high late-delivery probability, but buyers review the evidence before expediting or reallocating demand. A prescriptive scenario tool compares the cost of extra stock, dual sourcing and expedited transport.

Outcome

After two planning cycles, service performance improves while inventory value falls modestly. The largest improvement does not come from a sophisticated algorithm; it comes from correcting units of measure, exposing original-date supplier performance and removing inspection delays. The organization also learns that a lower purchase price did not represent lower total cost.

Learning points

The Orion case illustrates five principles:

  • KPI definitions can create false improvement or deterioration.
  • Diagnosis requires linking analytical results to process events.
  • Inventory, service, quality and cash must be managed as a system.
  • Automation should recommend and prioritize, while accountable managers retain decision authority.
  • Master data and governance are prerequisites for advanced analytics.

9. Governance, Ethics and Limitations

Materials analytics affects suppliers, employees, customers and financial outcomes. Governance should address data ownership, access control, audit trails, retention, model validation, cybersecurity and segregation of duties. A user who can alter supplier master data and approve a purchase order creates a significant control risk.

Supplier-risk models may reproduce historical bias. For example, small suppliers may appear risky because they have less complete data, not because they perform worse. Automated supplier exclusion should therefore include explainability, human review, appeal mechanisms and proportionality. Personal data, employee productivity data and external intelligence must be processed lawfully and only for legitimate purposes.

Important limitations include:

  • inaccurate or incomplete master data;
  • survivorship bias when failed suppliers disappear from the dataset;
  • changing definitions across plants or periods;
  • forecast instability during structural market change;
  • model drift as supplier and demand conditions change;
  • false precision in probabilistic outputs;
  • optimization based on incomplete cost or risk estimates;
  • organizational resistance and metric gaming.

A model should be monitored through back-testing, calibration, error analysis and outcome review. Managers should distinguish model uncertainty from business uncertainty. An apparently precise recommendation may be weak when demand, lead time or cost assumptions are uncertain.

10. Contemporary Developments and Best Practice

Cloud ERP and integrated analytics platforms increasingly provide near-real-time event monitoring. Process mining reconstructs actual procure-to-pay and order-to-cash processes from event logs, revealing rework, approval loops and bottlenecks. Digital twins can test inventory and network scenarios before operational implementation. Machine learning supports anomaly detection, demand sensing, ETA prediction and document extraction.

Generative AI can assist with natural-language explanations, supplier correspondence, query building and dashboard interpretation. It should not be trusted to invent KPI definitions, approve purchases or override controls without verification. Sensitive procurement information should be protected, and generated explanations should link to authoritative data.

Best practice is to:

  1. begin with business decisions rather than available data;
  2. standardize definitions and maintain a KPI catalogue;
  3. establish master-data ownership and quality controls;
  4. balance service, cost, cash, risk, quality and sustainability;
  5. use segmentation instead of one-size-fits-all targets;
  6. expose uncertainty, assumptions and data freshness;
  7. connect every exception to an owner and workflow;
  8. validate predictive and prescriptive models continuously;
  9. retain human accountability for material decisions;
  10. measure outcomes after intervention and learn from error.

Chapter Summary

Materials analytics converts ERP and supply-chain data into evidence for managerial action. Descriptive analytics reports what happened; diagnostic analytics investigates why; predictive analytics estimates what may happen; and prescriptive analytics evaluates what should be done under constraints. Effective KPI systems combine inventory, service, procurement, supplier, warehouse, quality, working-capital and risk measures rather than optimizing one dimension in isolation.

Important measures include inventory turnover, DIO, fill rate, inventory accuracy, OTD, lead-time variability, PPV, supplier defects, warehouse productivity and the cash conversion cycle. Their value depends on precise definitions, consistent units, reliable data and appropriate interpretation. Forecasting, reorder-point analysis, safety stock, economic order quantity and optimization models are useful only within their assumptions.

Dashboards should be designed around strategic, tactical and operational decisions. Diagnostic analysis must connect KPI deviations to process causes, while predictive and prescriptive tools should expose uncertainty and remain subject to governance. The Orion case demonstrates that master-data quality, transparent definitions and cross-functional action may create more value than algorithmic complexity. Ethical use requires security, explainability, fairness, auditability and accountable human oversight.

Key Terms

Materials analytics: The use of data, models and judgement to improve materials decisions.

KPI: A defined measure used to monitor performance against an objective or target.

Descriptive analytics: Analysis that summarizes historical or current conditions.

Diagnostic analytics: Analysis that investigates causes of observed results.

Predictive analytics: Analysis that estimates future values, events or probabilities.

Prescriptive analytics: Analysis that recommends actions under objectives and constraints.

Inventory turnover: Cost of goods sold divided by average inventory at cost.

Days inventory outstanding: Average inventory expressed as days of cost of goods sold.

Fill rate: The proportion of demand supplied immediately from available stock.

Cycle service level: The probability of avoiding a stockout during a replenishment cycle.

Purchase-price variance: The difference between actual and standard purchase price multiplied by actual quantity.

Lead-time variability: Variation in elapsed time between order placement and receipt.

Forecast bias: Persistent tendency of forecasts to overestimate or underestimate demand.

Safety stock: Inventory held to protect against demand, lead-time or supply uncertainty.

Reorder point: Inventory position at which replenishment should be initiated.

ABC analysis: Classification based commonly on annual usage value.

Working capital: Funds invested in operating assets and liabilities, including inventory and payables.

Process mining: Reconstruction and analysis of processes using event-log data.

Master data: Controlled reference data such as material, supplier, unit and location records.

Model governance: Controls for validation, use, monitoring, access and accountability of analytical models.

Review Questions

Short Answer Questions

  1. Distinguish descriptive, diagnostic, predictive and prescriptive analytics.
  2. Why are fill rate and cycle service level not interchangeable?
  3. State two conditions required for a meaningful KPI.
  4. What is the managerial purpose of segmenting inventory by ABC and XYZ categories?
  5. Why should purchase-price variance not be treated as a complete measure of procurement performance?

Long Answer Questions

  1. Explain how a materials-management dashboard should differ at strategic, tactical and operational levels.
  2. Discuss the assumptions and limitations of the reorder-point formula that includes demand and lead-time variability.
  3. Explain how diagnostic analytics can distinguish excess inventory caused by deliberate buffering from excess inventory caused by poor planning.
  4. Evaluate the relationship between inventory decisions and the cash conversion cycle.
  5. Discuss governance, ethical and organizational risks associated with predictive supplier-risk models.

Analytical / Application Questions

  1. A company has annual cost of goods sold of $18 million, opening inventory of $3 million and closing inventory of $5 million. Calculate average inventory, inventory turnover and DIO using 365 days. Interpret the results.
  2. A supplier delivered 460 of 500 purchase-order lines on or before the original required date. The business supplied 9,600 of 10,000 demanded units immediately. Calculate OTD and fill rate, and explain why the two results should be reviewed together.
  3. A plant reports rising inventory and falling service. Design a diagnostic investigation covering data validation, segmentation, root-cause analysis, predictive indicators and possible prescriptive actions.

Multiple Choice Questions with Answers

Question 1

Which type of analytics primarily investigates why a stockout occurred?

A. Descriptive analytics

B. Diagnostic analytics

C. Predictive analytics

D. Prescriptive analytics

Correct Answer: B. Diagnostic analytics

Question 2

A company has cost of goods sold of $12 million and average inventory at cost of $3 million. What is inventory turnover?

A. 0.25 turns

B. 3 turns

C. 4 turns

D. 9 turns

Correct Answer: C. 4 turns

Question 3

Which measure expresses the proportion of demand supplied immediately from available stock?

A. Fill rate

B. Inventory turnover

C. Purchase-price variance

D. Days payable outstanding

Correct Answer: A. Fill rate

Question 4

Under the chapter’s sign convention, what does a positive PPV indicate?

A. Actual price was below standard price

B. Actual price exceeded standard price

C. Actual quantity was below planned quantity

D. Supplier quality improved

Correct Answer: B. Actual price exceeded standard price

Question 5

Which is a limitation of MAPE?

A. It has no percentage interpretation

B. It cannot compare any forecasts

C. It becomes problematic when actual demand is zero or very small

D. It always detects forecast bias

Correct Answer: C. It becomes problematic when actual demand is zero or very small

Question 6

In the reorder-point formula with variable demand and lead time, the factor z represents the:

A. Average demand per period

B. Mean lead time

C. Standard-normal service factor

D. Annual holding cost

Correct Answer: C. Standard-normal service factor

Question 7

Which condition is assumed by the basic economic order quantity model?

A. Highly intermittent demand with frequent shortages

B. Stable demand and constant ordering and holding costs

C. Unlimited quantity discounts

D. Unknown unit costs

Correct Answer: B. Stable demand and constant ordering and holding costs

Question 8

A delivery KPI uses the latest confirmed date instead of the original required date. What is the principal analytical risk?

A. Supplier punctuality may be overstated

B. Inventory units will automatically increase

C. Forecast error will become zero

D. Warehouse capacity will double

Correct Answer: A. Supplier punctuality may be overstated

Question 9

Which action best represents prescriptive analytics?

A. Reporting last month’s inventory value

B. Listing overdue purchase orders

C. Estimating next month’s demand

D. Comparing supplier-allocation scenarios subject to capacity and service constraints

Correct Answer: D. Comparing supplier-allocation scenarios subject to capacity and service constraints

Question 10

Why should a dashboard display data freshness and KPI definitions?

A. To replace managerial judgement entirely

B. To help users assess interpretability and reliability of the result

C. To ensure every KPI has a red status

D. To eliminate the need for master-data controls

Correct Answer: B. To help users assess interpretability and reliability of the result

Digital Materials Management & ERP Systems
Chapter 12 of 15