Lane Group Research Articles

A behavioral theory of multi-lane traffic flow. Part I: Long homogeneous freeway sections

This paper proposes a macroscopic behavioral theory of traffic dynamics for homogeneous, multi-lane freeways. The theory makes predictions for separate groups of lanes while recognizing that the traffic stream is usually composed of aggressive and timid drivers. Its principles are so simple that non-scientist drivers can understand them. The simplest version of the theory, which is described in its full complexity without calculus, is shown to be qualitatively consistent with experimental observations, including the most puzzling. Its predictions agree with the following phenomena: (i) the ‘reversed lambda’ pattern frequently observed in scatter-plots of flow versus occupancy and the lane-specific evolution of the data points with time, including the ‘hysteresis’ phenomenon, (ii) the lane-specific patterns in the time series of speed (and flow) in both queued and unqueued traffic, and (iii) the peculiar ways in which disturbances of various types propagate across detector stations. The latter effects include the evolution of both, stoppages and transitions between the queued and unqueued traffic regimes. The simple model is specified by means of eight observable parameters. The paper gives a recipe for solving any well-posed problem with this model and does so in sufficient detail to allow the development of computer models. A few approaches and possible generalizations are suggested. Part II of this paper, devoted to freeway sections near on-ramps, will attempt to explain in more detail than previously attempted how queuing begins at merges.

Saturation Flow Estimation by Traffic Subgroups

A framework for the estimation of saturation flow rates at signal-controlled intersections is presented. The proposed framework is grounded in existing highway capacity theories found in U.S. and international highway capacity guides. It is intended to provide a high level of flexibility to the end user for analyzing complex approach configurations and signal control schemes. This flexibility is achieved through the decomposition of the traffic stream on an approach into a subset of homogeneous traffic subgroups, each of which has a unique average saturation flow headway. The proposed approach enables the analyst to produce saturation flow rates at multiple levels, ranging from turning-movement saturation flows on individual lanes (exclusive or shared) to overall approach estimates that can encompass multiple lane groups. The proposed framework can accommodate cases with uneven distribution of traffic across lanes because of lane impedance differentials or prepositioning. When assumptions similar to those found in the Highway Capacity Manual (HCM) were used, the model’s saturation flows were found to be virtually identical to those estimated by the 1997 HCM.

Analysis of Arrival Type Estimation Procedures

The estimation of arrival type, an important part of the 1997 Highway Capacity Manual (HCM) procedure for estimation of delay and level of service (LOS) at signalized intersections, is considered. The research examines whether arrival type can be reliably estimated by the procedures outlined in HCM. The objective is to review the impact that arrival type has on delay estimation and to evaluate quantitatively the variance and error of arrival types estimated under controlled conditions. Progression quality issues are discussed, and potential additions and clarifications are explored. To understand the impact that arrival type estimations have on delay results, an experiment was conducted using the HCM delay estimation procedure. Participants were shown video clips of traffic at seven different intersection approaches and were asked to indicate the observed arrival type. The results are categorized by response groups (traffic engineering professionals, high school students, and university students) and approaches and are compared, with results calculated by HCM procedure. The results show trends of inconsistent responses when the responses are compared within groups, between groups, and with the calculated arrival types. On the basis of the response trends, several additions to the HCM method are explored. Recommendations are to include the impact of green split percentages, estimation of arrival types for each lane group, and general clarification of instructions for estimation of arrival types. The study results suggest that these changes and clarifications should be considered for incorporation into the HCM delay estimation and LOS procedure for signalized intersections.

Graded extensions of categories

The problem of extending categories by groups, including theory of obstructions, is studied by means of factor systems and various homological invariants, generalized from Schreier–Eilenberg–Mac Lane group extension theory. Explicit applications are then given to the classification of several algebraic constructions long known as crossed products, appearing in many different contexts such as monoids, Clifford systems or twisted group rings.

Utilization of Auxiliary Through Lanes at Intersections of Four-Lane, Two-Way Roadways

To increase the capacity of through traffic at signalized intersections, additional lanes with limited length—called auxiliary lanes—are added to the roadway at the intersection. Because of their limited length, as well as other factors, these lanes are not as fully utilized as other continuous through lanes. Research was undertaken with two objectives: ( a) to observe and identify the level of use of auxiliary through lanes added at intersections of four-lane, two-way roadways; and ( b) to study the effects of auxiliary lane length, right-turn volume, and through/right-turn lane group delay on the level of their use. Lane-use data collected during 1,050 saturated cycles at eight signalized intersections with different auxiliary lane lengths were used to accomplish research objectives. All factors investigated—auxiliary lane length, right-turn volume, and stopped-delay—were found to contribute significantly to the use of auxiliary lanes at 0.01 level. The level of each factor’s contribution, however, was dependent on the level of the other two. Lane use of nearly one to seven straight-through vehicles per cycle, depending on levels of factors investigated, was observed at the study locations. Longer auxiliary lanes, lower right-turn volumes, and excessive approach delays encouraged the use of auxiliary lanes by straight-through vehicles. The range of lane utilization adjustment factors ( fLU-factors) calculated from field data was 0.73 to 0.82, which is lower than the 1997 Highway Capacity Manual default value of 0.91 for a three-lane through/right-turn group.

Analyzing Arterial Streets in Near-Capacity or Overflow Conditions

Filtering and metering of traffic at highway bottlenecks influence delay and travel speeds along congested arterial streets. The current Highway Capacity Manual (HCM) method of analyzing urban arterial streets uses the filtering and metering adjustment factor I but does not give recommendations on how to adjust traffic volumes. An improved method of analyzing signalized arterial streets affected by bottlenecks is proposed. A set of equations has been derived to calculate the coefficient I and to adjust the traffic volumes. Conditions in which measured or predicted volumes should be adjusted and conditions in which they do not have to be adjusted are specified. The proposed method incorporates the effect of turning volumes, a feature not present in the current HCM method. A sensitivity analysis of travel speeds along an example signalized arterial street illustrates the filtering and metering effects and compares the results produced by the existing and proposed methods. The differences in the results are considerable. In addition, the significant effect of turning volumes has been confirmed. The proposed method tends to produce travel speeds higher than the values obtained with the current method, which concurs with comments from the users of the HCM that the current method underestimates travel speeds. The filtering equation has been derived with the assumptions of fixed capacity and no vehicle dispersion. Under the conditions violating these assumptions, the filtering equation may underestimate I. Further, the proposed method does not incorporate the effect of long queues blocking upstream lane groups. The negative effect on travel speed estimates along the entire arterial should be limited or negligible.

Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase: a control enzyme in ketogenesis

Cytosolic and mitochondrial 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthases were first recognized as different chemical entities in 1975, when they were purified and characterized by Lane's group. Since then, the two enzymes have been studied extensively, one as a control site of the cholesterol biosynthetic pathway and the other as an important control site of ketogenesis. This review describes some key developments over the last 25 years that have led to our current understanding of the physiology of mitochondrial HMG-CoA synthase in the HMG-CoA pathway and in ketogenesis in the liver and small intestine of suckling animals. The enzyme is regulated by two systems: succinylation and desuccinylation in the short term, and transcriptional regulation in the long term. Both control mechanisms are influenced by nutritional and hormonal factors, which explains the incidence of ketogenesis in diabetes and starvation, during intense lipolysis, and in the foetal-neonatal and suckling-weaning transitions. The DNA-binding properties of the peroxisome-proliferator-activated receptor and other transcription factors on the nuclear-receptor-responsive element of the mitochondrial HMG-CoA synthase promoter have revealed how ketogenesis can be regulated by fatty acids. Finally, the expression of mitochondrial HMG-CoA synthase in the gonads and the correction of auxotrophy for mevalonate in cells deficient in cytosolic HMG-CoA synthase suggest that the mitochondrial enzyme may play a role in cholesterogenesis in gonadal and other tissues.

Capacity Study for Protected-Permitted Phasing from Shared Lanes

Protected-permitted phasing from shared-use lanes (i.e., no left-turn bays) exists in certain situations where space and other constraints make this measure expedient in the face of growing traffic demand. An alternative method for handling this special case is proposed as an enhancement to the existing treatment in the 1997 update to the Highway Capacity Manual. The method proposed is logical and consistent. The more practical issue of whether it is also more accurate is addressed in a series of simulation cases. Simulation was used to provide the reference conditions because of field costs, number of variables to be controlled, and the fact that a well-established model exists. The results show that the existing method systematically overestimates lane group capacity by 10 to 25 percent for this special case, whereas the proposed alternative estimates the lane group capacity by ±10 percent or less.

Innovative application of directional boring procedures for replacing failed inductive loop detectors

Actuated traffic signal controllers typically depend on inductive loop detectors to determine demand for a particular signal phase. The basic philosophy of these controllers is to only provide a green indication to a particular lane group when there is a vehicle waiting. If an inductive loop detector fails, it must be put in recall mode so that the lane group with the corresponding failed detector is serviced every cycle. When actuated controllers operate in this mode, the performance of the signalized intersection degenerates. Since the vast majority of actuated intersections operate with inductive loop detectors it is useful to have maintenance procedures that can be used to replace loop detectors that have failed due to pavement distress. This paper describes a procedure that has been developed using directional boring equipment to install a micro loop below the surface of the pavement where it is not subject to pavement distress. The authors believe this procedure will provide a cost effective method of restoring actuated control on approaches or lanes groups where the pavement condition makes it unfeasible to install or re-install a traditional saw cut loop detector.

Modified Delay Equations for Permitted Left Turns

For permitted left turns at signalized intersections from exclusive or shared lane groups with multiple opposing lanes, this paper proposes modifications to the delay equation used in the 1994 Highway Capacity Manual (HCM). In the 1994 HCM, the green time for left turns is reduced by the opposing queue clearance time in the worksheet calculation of a left-turn adjustment factor that reduces the saturation flow rate of the left-turn lane group. A difficulty with the 1994 HCM is that it uses this saturation flow rate in a delay equation that allows vehicles to make “slow” left turns from the instant the green time begins. These vehicles actually make “no” left turns until the opposing traffic is less saturated, and then make “faster” left turns as acceptable gaps allow. This modified delay always exceeds the 1994 HCM delay for exclusive left-turn lanes (by more than 50% over total delay in some cases) but may either increase or decrease the HCM delay for shared lanes. Both delays are compared over a range o...

Effect of Bicycles on Capacity of Signalized Intersections

Although much is known about the operation of signalized intersections, little or no empirical research has been conducted regarding the effect of bicycles on signalized intersection capacity. The purpose of this study was to accurately quantify the effects of bicycles on signalized intersection capacity through the videotaping of several intersections that had significant bicycle traffic. Through the videotaping of intersections in Davis, California, and Gainesville, Florida, a relationship was determined between bicycle volumes and the percent of the green phase during which bicycle traffic occupies a conflict zone between bicycles and right-turning motor vehicles. It was also determined that one can ascertain the total net occupancy due to pedestrians and bicycles by taking the overlapping effects between bicycles and pedestrians into account. Using this total occupancy due to bicycles and pedestrians, one can calculate a saturation flow adjustment factor ( fRph) that reflects the reduction in saturation flow, and ultimately lane group capacity, for lane groups containing vehicles making permissive right turns in the presence of bicycles and pedestrians. The proposed procedure yields lower saturation flows and capacities than the current Highway Capacity Manual (HCM) procedure. In other words, on the basis of empirical data, when combined with pedestrian effects, the impact of bicycles on the saturation flow of lane groups containing right-turning vehicles is probably more detrimental than previously believed, and the capacities of intersections with significant bicycle and pedestrian traffic may be overestimated by using the current HCM procedures.

Effect of Pedestrians on Capacity of Signalized Intersections

In Chapter 9 of the 1994 update to the 1985 Highway Capacity Manual, the operational and planning analysis of signalized intersections is discussed. The methodology for saturation flow rate estimation does not consider all elements of the interaction between pedestrians and turning vehicles. This study describes this interaction for left and right turns using a conflict-zone-occupancy approach. A conflict zone is a portion of an intersection, typically in the crosswalk, in which pedestrians and vehicles compete for space. Conflict-zone occupancy, defined as the fraction of the effective green period during which pedestrians occupy a conflict zone, provides the basis for a rational adjustment to saturation flow. This study details the results of a multiregional data collection effort that confirms the validity of the conflict-zone-occupancy approach. In addition, this study describes the effect of geometric constraints, as reflected in the number of receiving lanes versus the number of turning lanes, on turning-vehicle saturation flow. After consideration of signalized intersection phasing and turn protection, one can calculate saturation flow adjustment factors reflecting the effect of pedestrians on lane groups containing vehicles turning left ( fLpb) or right ( fRpb).

Comparison of Planning and Operational Analysis Procedures for Signalized Intersections from the Highway Capacity Manual

The 1994 update of the Highway Capacity Manual (HCM) includes a planning procedure to estimate the capacity condition of a signalized intersection (Xcm). The planning method results can also be extended to a planning application of the more data-intensive HCM operational procedure to estimate intersection critical flow-to-capacity ratio (Xc) and level of service with only planning-level data. Both the planning procedure and the planning application of the operational procedure involve default adjustment factors and synthesized traffic signal timing (called the “default signal timing”). Data from 166 Missouri intersections were used to determine how well the planning approaches predict operational analysis results. In general, the default signal timings had shorter cycle lengths than the timing plans used at pretimed signals. The shorter cycle lengths led to slightly higher flow-to-capacity ratios, since a higher proportion of each cycle was devoted to lost time. The default signal timings also had more equal flow-to-capacity ratios within critical lane groups. The shorter cycle lengths and more equal flow-to-capacity ratios led to a predicted level of service that was the same or better than that calculated for actual conditions. For the subject intersections, locally calibrated default adjustment factors yielded better predictions of flow-to-capacity ratios and level of service than the HCM defaults. The planning value for Xcm was often less than the actual Xc for operational analysis of actual conditions. This was to be expected since Xcm is based on the maximum allowable cycle length. The HCM planning procedure is expected to receive wide use in a variety of planning and design applications. Calibration of appropriate local default values should improve the accuracy of the planning procedure results.

Estimating Intersection Approach Delay Using 1985 and 1994Highway Capacity ManualProcedures

The current methods for determining average stopped delay at signalized intersections were studied. Field measurements of average stopped delay were obtained and compared with values computed using both the 1985 and 1994 editions of the Highway Capacity Manual (HCM). The 1994 HCM uses an equation to predict the progression adjustment factor (PF), a new technique for determining the left-turn adjustment factor for saturation flow rates, and a new set of equations for determining the uniform delay parameter for left-turn lane groups with primary and secondary phasing. Overall, the 1994 HCM produces better estimates of intersection stopped delay than the 1985 HCM.

Estimating Intersection Approach Delay Using 1985 and 1994 Highway Capacity Manual Procedures

The current methods for determining average stopped delay at signalized intersections were studied. Field measurements of average stopped delay were obtained and compared with values computed using both the 1985 and 1994 editions of the Highway Capacity Manual (HCM). The 1994 HCM uses an equation to predict the progression adjustment factor (PF), a new technique for determining the left-turn adjustment factor for saturation flow rates, and a new set of equations for determining the uniform delay parameter for left-turn lane groups with primary and secondary phasing. Overall, the 1994 HCM produces better estimates of intersection stopped delay than the 1985 HCM.

Estimation of right turn on red saturation flow rates

It is common practice in most Canadian provinces to permit right turns on red at signalized intersections. At intersections with a high volume of pedestrian traffic, the opportunity to turn right on red may be critical to satisfy right turn demand. However, in order to properly time the traffic control signal display at a signalized intersection, the saturation flow rates for each lane or lane group of the intersection must be known. Six signalized intersections were studied in Kingston, Ontario, where saturation flow rates for right turns were measured as a function of conflicting through traffic. From these measurements, estimations of the gap size required for a right turn movement were made. A regression analysis resulted in the production of a simple equation for estimating right turn on red saturation flow rates. It was found that the gap acceptance behaviour of drivers varied both spatially and temporally. Key words: saturation flow rates, signalized intersections, capacity, gap acceptance.

Antiretroviral Therapy: Reference Guide to Major Clinical Trials in Patients Infected with Human Immunodeficiency Virus

Physicians have difficulty keeping up with the rapidly evolving field of antiretroviral chemotherapy. Dr. Henry Masur's and Dr. Clifford Lane's group at the National Institutes of Health has maintained an up-to-date file, in tabular form, of the results of clinical trials. The tables are based on published articles and abstracts and contain each study's stated conclusions and subjective comments based upon the group's interpretation of the results of each trial. Clinical Infectious Diseases plans to publish an update of these summary tables annually as an AIDS Commentary. Our goal is to aid physicians in providing care to individuals infected with HIV type 1. -John P. Phair

Computerized Solution for Signalized Intersection Service Volumes

The 1985 Highway Capacity Manual defines level of service as a function of the average vehicular stopped delay. The complexity of the equation to calculate this delay, however, makes the determination of service volumes required to produce a desired delay very difficult. Simple computerized techniques can be used for intersections where permitted phasing is not provided. Iterative solutions are required, however, where permitted phasing is provided. An iterative procedure to determine initial estimates of the service volumes for each lane group required to produce a desired delay is described and verified. After the initial solutions are obtained, the shared lane groups are checked for de‐facto left‐turn lanes. If necessary, the computations are repeated for each of these lane groups assuming an exclusive left‐turn lane with permitted signal phasing.

Principles of highway engineering and traffic analysis

Chapter 1: Introduction to Highway Engineering and Traffic Analysis. 1.1 Introduction. 1.2 Highways and the Economy. 1.2.1 The Highway Economy. 1.2.2 Supply Chains. 1.2.3 Economic Development. 1.3 Highways, Energy and the Environment. 1.4 Highways and the Transportation System. 1.5 Highway Transportation and the Human Element. 1.5.1 Passenger Transportation Modes and Traffic Congestion.1.5.2 Highway Safety.1.5.3 Demographic Trends.1.6 Highways and Evolving Technologies.1.6.1 Infrastructure Technologies.1.6.2 Vehicle Technologies. 1.6.3 Traffic Control Technologies.1.7 Scope of Study. Chapter 2: Road Vehicle Performance. 2.1 Introduction. 2.2 Tractive Effort and Resistance. 2.3 Aerodynamic Resistance. 2.4 Rolling Resistance. 2.5 Grade Resistance. 2.6 Available Tractive Effort. 2.6.1 Maximum Tractive Effort. 2.6.2 Engine-Generated Tractive Effort. 2.7 Vehicle Acceleration. 2.8 Fuel Efficiency. 2.9 Principles of Braking. 2.9.1 Braking Forces. 2.9.2 Braking Force Ratio and Efficiency. 2.9.3 Antilock Braking Systems. 2.9.4 Theoretical Stopping Distance. 2.9.5 Practical Stopping Distance. 2.9.6 Distance Traveled During Driver Perception/Reaction. Chapter 3: Geometric Design of Highways. 3.1 Introduction. 3.2 Principles of Highway Alignment. 3.3 Vertical Alignment. 3.3.1 Vertical Curve Fundamentals. 3.3.2 Stopping Sight Distance. 3.3.3 Stopping Sight Distance and Crest Vertical Curve Design. 3.3.4 Stopping Sight Distance and Sag Vertical Curve Design. 3.3.5 Passing Sight Distance and Crest Vertical Curve Design. 3.3.6 Underpass Sight Distance and Sag Vertical Curve Design. 3.4 Horizontal Alignment. 3.4.1 Vehicle Cornering. 3.4.2 Horizontal Curve Fundamentals. 3.4.3 Stopping Sight Distance and Horizontal Curve Design. 3.5 Combined Vertical and Horizontal Alignment. Chapter 4: Pavement Design. 4.1 Introduction. 4.2 Pavement Types. 4.2.1 Flexible Pavements. 4.2.2 Rigid Pavements 95. 4.3 Pavement System Design: Principles for Flexible Pavements. 4.3.1 Calculation of Flexible Pavement Stresses and Deflections. 4.4 The AASHTO Flexible-Pavement Design Procedure. 4.4.1 Serviceability Concept. 4.4.2 Flexible-Pavement Design Equation. 4.4.3 Structural Number. 4.5 Pavement System Design: Principles for Rigid Pavements. 4.5.1 Calculation of Rigid-Pavement Stresses and Deflections. 4.6 The AASHTO Rigid-Pavement Design Procedure. 4.7 Measuring Pavement Quality and Performance. 4.7.1 International Roughness Index. 4.7.2 Friction Measurements. 4.7.3 Rut Depth. Chapter 5: Fundamentals of Traffic Flow and Queuing Theory. 5.1 Introduction. 5.2 Traffic Stream Parameters. 5.2.1 Traffic Flow, Speed, and Density. 5.3 Basic Traffic Stream Models. 5.3.1 Speed-Density Model. 5.3.2 Flow-Density Model. 5.3.3 Speed-Flow Model. 5.4 Models Of Traffic Flow. 5.4.1 Poisson Model. 5.4.2 Limitations of the Poisson Model. 5.5 Queuing Theory and Traffic Flow Analysis. 5.5.1 Dimensions of Queuing Models. 5.5.2 D/D/1 Queuing. 5.5.3 M/D/1 Queuing. 5.5.4 M/M/1 Queuing. 5.5.5 M/M/N Queuing. 5.6 Traffic Analysis at Highway Bottlenecks. Chapter 6: Highway Capacity and Level-of-Service Analysis. 6.1 Introduction. 6.2 Level-of-Service Concept. 6.3 Level-of-Service Determination. 6.3.1 Base Conditions and Capacity. 6.3.2 Determine Free-Flow Speed. 6.3.3 Determine Analysis Flow Rate. 6.3.4 Calculate Service Measure(s) and Determine LOS. 6.4 Basic Freeway Segments. 6.4.1 Base Conditions and Capacity. 6.4.2 Service Measure. 6.4.3 Determining Free-Flow Speed. 6.4.4 Determining Analysis Flow Rate. 6.4.5 Calculating Density and Determining LOS. 6.5 Multilane Highways. 6.5.1 Base Conditions and Capacity. 6.5.2 Service Measure. 6.5.3 Determining Free-Flow Speed. 6.5.4 Determining Analysis Flow Rate. 6.5.5 Calculating Density and Determining LOS. 6.6 Two-Lane Highways. 6.6.1 Base Conditions and Capacity. 6.6.2 Service Measures. 6.6.3 Determining Free-Flow Speed. 6.6.4 Determining Analysis Flow Rate. 6.6.5 Calculate Service Measures. 6.6.6 Determine LOS. 6.7 Design Traffic Volumes. Chapter 7: Traffic Control and Analysis at Signalized Intersections. 7.1 Introduction. 7.2 Intersection and Signal Control Characteristics. 7.2.1 Actuated Control. 7.2.2 Vehicle Detection. 7.2.3 Typical Phase Operation. 7.2.4 Signal Controller Operation. 7.3 Analysis of Traffic at Signalized Intersections. 7.3.1 Concepts and Definitions. 7.3.2 Signalized Intersection Analysis with D/D/1 Queuing. 7.3.3 Signalized Intersection Analysis for Level of Service. 7.4 Optimal Traffic Signal Timing. 7.5 Development of a Traffic Signal Phasing and Timing Plan. 7.5.1 Select Signal Phasing. 7.5.2 Establish Analysis Lane Groups. 7.5.3 Calculate Analysis Flow Rates and Adjusted Saturation Flow Rates. 7.5.4 Determine Critical Lane Groups and Total Cycle Lost Time. 7.5.5 Calculate Cycle Length. 7.5.6 Allocate Green Time. 7.5.7 Calculate Change and Clearance Intervals. 7.5.8 Check Pedestrian Crossing Time. 7.6 Level-of-Service Determination. 7.7 Signal Coordination. 7.7.1 Fundamental Relationships. 7.7.2 Effective Green to Cycle Length Ratio (g/C). 7.7.3 Platoon Dispersion. 7.7.4 State of the Practice. 7.7.5 Progression Quality and Level of Service Analysis. 7.8 The Progression Adjustment Factor and Arrival Type. Chapter 8: Travel Demand and Traffic Forecasting. 8.1 Introduction. 8.2 Traveler Decisions. 8.3 Scope of the Travel Demand and Traffic Forecasting Problem. 8.4 Trip Generation. 8.4.1 Typical Trip Generation Models. 8.4.2 Trip Generation with Count Data Models. 8.5 Mode and Destination Choice. 8.5.1 Methodological Approach. 8.5.2 Logit Model Applications. 8.6 Highway Route Choice. 8.6.1 Highway Performance Functions. 8.6.2 User Equilibrium. 8.6.3 Mathematical Programming Approach to User Equilibrium. 8.6.4 System Optimization. 8.7 Traffic Forecasting in Practice. 8.8 The Traditional Four-Step Process. 8.9 The Current State of Travel Demand and Traffic Forecasting. Appendix 8A: Least Squares Estimation. Appendix 8B: Maximum-Likelihood Estimation. Appendix A: Metric Example Problems. Appendix B: Metric End-of-Chapter Problems. Index.

Homology of integral upper-triangular matrices

We calculate the homology of the multiplicative group of integral upper-triangular n × n n \times n matrices at all primes p ⩾ n − 1 p \geqslant n - 1 .