Strike Incidence Research Articles

Employee militancy in Britain: 1985-1990

This paper profiles individual strike incidence and militancy in Britain over the period 1985–1990 using data derived from the British Social Attitudes Survey. The approach of the study is to quantify the differential probabilities of strike activity and other forms of militant behaviour of particular groups within the population. Following studies from the USA in highlighting, in particular, the role of demographic and attitudinal influences. The results indicate that demographic influences are, in general, the key correlates of strike incidence and militancy ceteris paribus.

AGE AND SEX DIFFERENCES IN THE SIZE OF PREY OF THE SHARP-SHINNED HAWK

We trapped Sharp-shinned Hawks (Accipiter striatus) during fall migration, using House Sparrows (Passer domesticus), European Starlings (Sturnus vulgaris), and Ringed Turtle Doves (Streptopelia risoria) as lures. Adults and males initiated attacks on sparrows more frequently than juveniles and females. Adult females initiated attacks on starlings and doves more often than adult males, but there was no such difference between the sexes in juveniles. Females actually struck all three species of lure more frequently than males, and juvenile females struck lures more frequently than adult females. There was no age difference in the incidence of strikes by males. Larger (longer-winged) juvenile males and females attacked starlings more often than smaller juveniles, but there were no size differences in strikes on prey in any age and sex group of hawks, suggesting that sexual dimorphism in size is not a result of selection for differences in prey size. Females struck disproportionately larger lures than males, presumably because they are less efficient at capturing smaller prey. Juveniles attacked doves as frequently as starlings, and there was little age difference in the incidence of strikes, suggesting that inexperience in judging the size of prey is an inadequate explanation for the many attacks that fail to result in strikes.

Commitment and strikes in wage bargaining

This paper analyzes the long-run strategic relationship between a firm and a union as a repeated bargaining game, where there is incomplete information on the player's motivation on both sides and each party has a fall-back position. The firm and the union will engage in a reputation-building activity, that will produce a limited number of strikes over time. The bargainer that succeeds in building up a reputation for toughness and obtains a favorable payoff in the long-run is, either the more patient (or alternatively the more centralized), or the party with a higher initial probability of stubbornness, or the party with a smaller fall-back position. Our model also offers predictions on the dependence of strike incidence over time on several parameters.

Atlantic hurricanes and NW Pacific typhoons: ENSO spatial impacts on occurrence and landfall

Hurricanes are the United States' costliest natural disaster. Typhoons rank as the most expensive and deadly natural catastrophe affecting much of southeast Asia. A significant contributor to the year‐to‐year variability in intense tropical cyclone numbers in the north Atlantic and northwest Pacific is ENSO — the strongest interannual climate signal on the planet. We establish for the first time: (1) the spatial (0.5 degree grid) impacts of ENSO on the basin‐wide occurrence and landfall strike incidence of hurricanes and typhoons; (2) the spatial (7.5 degree grid or US state level) statistical significance behind the different incidence rates in warm and cold ENSO episodes; and (3) the effect of strengthening ENSO on regional strike rates and significances (hurricanes only). Our data comprise 98 years (1900–97) for the Atlantic and 33 years (1965–97) for the NW Pacific. At the US state level, we find several regions where the difference in landfalling incidence rate between warm and cold ENSO regimes is significant at the 90% level or higher. Our findings offer promise of useful long‐range predictability to seasonal forecasts of landfalling tropical cyclones.

The Law and Labor Strife in the United States, 1881–1894

This article examines the effect of state-level legal innovations governing labor disputes in the late 1800s. This was a period of legal ferment in which worker organizations and employers actively lobbied state governments for changes in the rules governing labor disputes. Cross-state heterogeneity in the legal environment provides an unusual opportunity to investigate the effects of these laws. We use a unique data set with information on 12,965 strikes to show that most of these law changes had surprisingly little effect on strike incidence or outcomes. Important exceptions were maximum hours laws and the use of injunctions.

The Law and Labor Strife in the United States, 1881–1894

This article examines the effect of state-level legal innovations governing labor disputes in the late 1800s. This was a period of legal ferment in which worker organizations and employers actively lobbied state governments for changes in the rules governing labor disputes. Cross-state heterogeneity in the legal environment provides an unusual opportunity to investigate the effects of these laws. We use a unique data set with information on 12,965 strikes to show that most of these law changes had surprisingly little effect on strike incidence or outcomes. Important exceptions were maximum hours laws and the use of injunctions.

Bird strike incidence at Addis Ababa Bole International Airport

The time and rate of bird strike incidences, species composition and number of birds involved in strikes, and the behaviour of birds were recorded at Bole International Airport from December 1994 to December 1995. The gut contents of the birds struck by aircraft were analyzed. A total of 33 bird strikes were recorded during the study period. Fifteen species of birds were involved in the strikes. Pigeons (Speckled pigeons, White-collard pigeons and Red eyed doves together), Black kites and Eurasian bee-eaters were responsible for 33, 24 and 18% of all the strikes recorded, respectively. Most bird strikes took place between September and October while the number of bird strikes between May and June were the least. Most of the bird strikes occurred in the early mornings when most flights leave or arrive. In 69% of the gut analysis carried out, the stomachs or crops were found empty mainly because strikes occurred in early mornings before the birds had fed. The bird strike prevention measures suggested include biological and physical methods. SINET: Ethiopian Journal of Science Vol. 23, No. 2 (December 2000), pp. 215-229 Key words/phrases: Airport, behaviour, bird strike, Bole

Hypothenar hammer syndrome: Proposed etiology

Purpose: Finger ischemia caused by embolic occlusion of digital arteries originating from the palmar ulnar artery in a person repetitively striking objects with the heel of the hand has been termed hypothenar hammer syndrome (HHS). Previous reports have attributed the arterial pathology to traumatic injury to normal vessels. A large experience leads us to hypothesize that HHS results from trauma to intrinsically abnormal arteries. Methods: We reviewed the arteriography, histology, and clinical outcome of all patients treated for HHS in a university clinical research center study of hand ischemia, which prospectively enrolled more than 1300 subjects from 1971 to 1998. Results: Twenty-one men had HHS. All had occupational (mechanic, carpenter, etc) or avocational (woodworker) exposure to repetitive palmar trauma. All patients underwent upper-extremity and hand arteriography, unilateral in eight patients (38%) and bilateral in 13 patients (62%). By means of arteriogram, multiple digital artery occlusions were shown in the symptomatic hand, with either segmental ulnar artery occlusion in the palm or characteristic “corkscrew” elongation, with alternating stenoses and ectasia. Similar changes in the contralateral asymptomatic (and less traumatized) hand were shown by means of 12 of 13 bilateral arteriograms (92%). Twenty-one operations, consisting of segmental ulnar artery excision in the palm and vein grafting, were performed on 19 patients. Histology was compatible with fibromuscular dysplasia with superimposed trauma. Patency of arterial repairs at 2 years was 84%. One patient (5%) required amputative debridement of necrotic finger tips. No other tissue loss occurred. There have been no recurrences of ischemia in patients with patent bypass grafts. Conclusion: To our knowledge, this is the largest reported group of HHS patients. The characteristic angiographic appearance, histologic findings, and striking incidence of bilateral abnormalities in patients with unilateral symptoms lead us to conclude that HHS occurs when persons with preexisting palmar ulnar artery fibrodysplasia experience repetitive palmar trauma. This revised theory for the etiology of HHS explains why HHS does not develop in most patients with repetitive palmar trauma. (J Vasc Surg 2000;31:104-13.)

Learning in Sequential Wage Negotiations: Theory and Evidence

When union‐firm pairs bargain sequentially, and when unobserved components of firms' abilities to pay are subject to correlated shocks, unions that bargain later in a sequence can acquire valuable information by observing previous bargaining outcomes in their industry. We derive the implications of this kind of learning in an asymmetric information model of wage negotiations and argue that the most robust implication is a lower incidence of strikes among “followers” than “leaders” in wage negotiations. Considerable empirical support for this implication is found in a long panel of Canadian contract negotiations.

The effect of farm management strategies on the incidence of sheep strike in Britain: a simulation analysis

A deterministic model is used to simulate the seasonal incidence of sheep myiasis (strike) on farms in Britain and to explore the effects of different farm management strategies on strike incidence. The model is based on two sub-components: the seasonal pattern of abundance of the primary agent of sheep myiasis in northwest Europe, the blowfly Lucilia sericata and the range of factors known to influence ewe and lamb susceptibility to strike. The results of these simulations show that familiar farm management strategies, such as shearing, reduction in scouring caused by endoparasitic worms and insecticide use can have an important role in the reduction of strike incidence in ewes and lambs. However, the effectiveness of these techniques can be highly dependent of their timing in relation to seasonal changes in blowfly abundance and the effects of temperature and rainfall.

Efficacy of ivermectin in a controlled-release capsule for the control of breech strike in sheep.

To investigate the efficacy of ivermectin in an intraruminal controlled-release capsule (CRC) against blowfly strike. Pen and field trials with controls. Pen studies: Two breech strike trials involving 60 Romney and 60 Merino sheep. One body strike trial using 100 Merino sheep. Field trials: Eight trials in New Zealand used 1000 Romney and Romney-cross sheep. Fifty Merino lambs in one trial in Australia. Pen studies: Sheep were allocated to two equal groups. One was not treated, the other sheep received a CRC that delivered ivermectin at > or = 20 micrograms/kg/day for 100 days. In the breech strike trials, each animal was given an oral laxative 2 days before exposure to adult Lucilia cuprina. In the body-strike trial, the sheep sheep were kept wet to increase susceptibility prior to the release of blowflies. Field trials: Fifty or 200 sheep allocated to equal groups of nontreated or treated with the CRC and grazed at pasture exposed to natural blowfly challenge. Pen studies: Breech strikes developed in 24 of 60 controls but in none of 60 CRC-treated sheep. There was a 35% reduction in the number of CRC-treated sheep struck on the body. Field trials: The average number of breech strikes in CRC-treated sheep was reduced by 86% (P < 0.001). The number of body strikes in the treated groups was a reduced by 27% (P < 0.05). The ivermectin CRC is a useful aid in controlling breech strike, but provides only moderate reduction in the incidence of body strike.

The incidence of sheep strike by Lucilia sericata on sheep farms in Britain: a simulation model

Using a combination of a temperature-dependent simulation of the population dynamics of Lucilia sericata and a logistic model of sheep susceptibility, based on patterns of faecal soiling, fleece length and fleece humidity, a deterministic simulation model has been constructed to predict the incidence of sheep strike by L. sericata on lambs and ewes in Britain. Strikes are assigned to individual sheep in the flock according to a negative binomial distribution. The model shows that the majority of the first strikes of the season occur equally on ewes and lambs, when ewe fleeces are long and before lamb susceptibility increases through faecal soiling. With each subsequent generation of gravid blowflies, however, a greater proportion of strikes occur on lambs, while the number of strikes observed on ewes remains relatively consistent throughout the season. The increase in strike of lambs is due to the seasonal increase in lamb faecal soiling, associated with rising helminth infections and lamb fleece growth. The model shows that at the beginning of the season the incidence of strike is limited by the low number of flies present; towards the end of season, however, the blowfly population had grown large enough for the number of strikes to be limited by the number of susceptible ewes and lambs. The model shows that the seasonal incidence of strike is highly sensitive to the interactions between temperature, rainfall and wool length. Strike was most prevalent under warm, wet conditions. However, there is a critical period during spring, where the short fleeces of lambs and ewes, in the latter case due to shearing, results in the desiccation of egg batches. If this coincides with dry conditions, the high levels of mortality result in suppression of the fly population and a reduction in the subsequent incidence of strike.

Taxes, Strikes and Wages

A union and a firm bargain about wage increases. The firm possesses private information about its revenues. A two‐period screening model is used to derive equilibrium wage demands by the union and to calculate measures of strike activity. Changes in wage demands and dispute probabilities due to alterations in various taxes are analysed. A more progressive income tax, a lower level of income taxes and higher payroll taxes reduce wages and strike activity. Hence, tax policy can be used not only to affect wages and employment, but lso to influence strike incidence.

Inventories and Strikes

This paper analyses a dynamic model of bargaining and strikes in which the reservation wage of union members in each period is private information. The model endogenizes the firm's decision to accumulate inventories of finished goods in order to enhance its bargaining position. With higher inventories, the firm makes a lower wage offer, thereby accepting an increased probability of a strike. The model can help explain empirical results that have found a positive correlation between wages and inventory accumulation. It also shows that, unless inventories are controlled for, strike incidence will exhibit a spurious negative state dependence.

Sensitivity Analysis of a Stochastic Model for the Sheep Blowfly Lucilia sericata

Using empirically derived relationships between temperature and development rate, a stochastic simulation model was used to predict the seasonal pattern of abundance of the sheep blowfly Lucilia sericata. Sensitivity analysis suggests that, at the levels of mortality observed on sheep farms in Britain, L. sericata abundance may not be strongly influenced by the number of oviposition sites available. Hence, control techniques aimed at reducing the number of sites in the field may have little impact on the blowfly population and the resulting incidence of sheep strike. The model shows that variations in adult mortality have a much greater effect on the blowfly population than variations in pre-adult mortality, both in terms of the number of flies present in each generation and the probability of extinction of the population. With levels of pre-adult mortality of 50% per generation, adult mortality levels in excess of 30% per day would be needed to prevent the growth of a population of L. sericata. In contrast, at the lowest level of adult mortality examined, pre-adult mortality levels of 90% per generation were unable to prevent the population from increasing. The simulations suggest that unless consistently high levels of larval mortality can be maintained by a control programme, suppression of a L. sericata population is unlikely to be achieved. In contrast, relatively small increases in adult mortality may have a significant impact on L. sericata abundance, and attempts to suppress L. sericata populations by targeting the adult population may be an effective future approach.

Neuroblastoma and insulin-like growth factor system. New insights and clinical perspectives.

Neuroblastoma is, at the same time, the most common and the most puzzling extracranial solid tumour in childhood, being able to regress spontaneously despite widespread dissemination, showing a striking high incidence of the in situ form, and, finally, being resistant even to aggressive chemotherapy. The reasons of this bizarre behaviour are still largely unknown due to our little knowledge of neuroblastoma pathophysiology. There is increasing body of evidence that the insulin-like growth factor system plays a crucial role in the proliferation and differentiation of neuroblastoma cells and it is conceivable that a better knowledge of this role might potentially lead to new and more effective therapeutic strategies. Here we review the most recent insights into the biology of neuroblastoma, focusing on the close links with the insulin-like growth factor system and the potential clinical perspectives.

Factors affecting pilot‐reported bird‐strike rates at Christchurch International Airport, New Zealand

Pilots’ reports of their aircraft striking birds or having near misses at Christchurch International Airport from 1981 to 1993 were analysed to identify factors influencing the rate of such incidents. A preliminary analysis indicated that reporting of near misses was not influenced by recent bird strike incidents, which suggested that the data were reasonably robust to variation in pilot awareness of the problem. A total of 362 strikes was reported during the survey period, most commonly involving sparrows and gulls. Pilots were more likely to report near misses if the birds were large (e.g., gulls Larus spp., spur‐winged plover Vanellus miles novaehollandiae, white‐backed magpies Gymnorhina spp., and Australasian harrier Circus approximans) than if they were small (e.g., sparrows Passer domesticus and finches Carduelis spp.). The risk of an aircraft being struck varied both diurnally and seasonally, being highest at 0800–1000 h and in April. Birds seemed better able to avoid Boeing 737s than the quieter Boeing 767s and Whisper Jets. Bird‐strike rates increased progressively in the early and mid 1980s, but this increase appears to have been halted through an intensive bird management programme in place since 1987 and restrictions on agricultural activity and urban refuse near the airport. However, quarterly bird‐strike rates have been significantly more variable since 1987; the reason for this is unclear. A preliminary cost/benefit analysis of this management programme is presented.

Positional cloning of genes involved in the Beckwith‐Wiedemann syndrome, hemihypertrophy, and associated childhood tumors

The Beckwith-Wiedemann syndrome (BWS) is an overgrowth malformation syndrome that occurs with an incidence of 1:13,700 births. There is a striking incidence of childhood tumors found in BWS patients. Various lines of investigation have localized “imprinted” genes involved in BWS and associated childhood tumors to 11p15. High resolution mapping of 8 rare balanced chromosomal BWS rearrangements enabled us to identify three distinct regions on chromosome 11p15 that might harbor genes involved in the above-mentioned disorders. These results suggest genetic heterogeneity that correlates with the clinical heterogeneity seen in the patients studied. Expressed candidate gene sequences from these regions have been cloned and partly sequenced. These transcripts are either disrupted by or are at least within a few kb of these BWS chromosome breakpoints. So far, zinc-finger sequences and one KRAB domain were found in independent candidate genes which are compatible with a regulating function of growth promoting genes. The abundance of expression of these genes varies from low abundant in all adult and fetal tissues tested to detectable on Northern blots of adult tissues. In addition to our 11p15 studies we have analyzed additional chromosome regions, in particular 1p. Cytogenetic, loss of heterozygosity (LOH) and comparative genetic hybridization (CGH) studies have identified 1p35 as a region of interest. A positional cloning effort to identify a balanced 1p35 translocation found in a Wilms tumor has led to the isolation of a YAC, crossing this breakpoint. © 1996 Wiley-Liss, Inc.

Positional cloning of genes involved in the Beckwith-Wiedemann syndrome, hemihypertrophy, and associated childhood tumors.

The Beckwith-Wiedemann syndrome (BWS) is an overgrowth malformation syndrome that occurs with an incidence of 1:13,700 births. There is a striking incidence of childhood tumors found in BWS patients. Various lines of investigation have localized "imprinted" genes involved in BWS and associated childhood tumors to 11p15. High resolution mapping of 8 rare balanced chromosomal BWS rearrangements enabled us to identify three distinct regions on chromosome 11p15 that might harbor genes involved in the above-mentioned disorders. These results suggest genetic heterogeneity that correlates with the clinical heterogeneity seen in the patients studied. Expressed candidate gene sequences from these regions have been cloned and partly sequenced. These transcripts are either disrupted by or are at least within a few kb of these BWS chromosome breakpoints. So far, zinc-finger sequences and one Kruppel-associated box (KRAB) domain were found in independent candidate genes which are compatible with a regulating function of growth promoting genes. The abundance of expression of these genes varies from low abundant in all adult and fetal tissues tested to detectable on Northern blots of adult tissues. In addition to our 11p15 studies we have analyzed additional chromosome regions, in particular 1p. Cytogenetic, loss of heterozygosity (LOH) and comparative genomic hybridization (CGH) studies have identified 1p35 as a region of interest. A positional cloning effort to identify a balanced 1p35 translocation found in a Wilms tumor has led to the isolation of a YAC, crossing this breakpoint.

STRIKE BEHAVIOUR WHEN MARKET SHARE MATTERS

This paper analyzes the dynamics of strike incidence when a firm's market share affects its future profitability. Inventory accumulation is assumed to be impossible, so during a strike sales are zero, thereby reducing future demand. Anticipation of the future effects of a strike leads to lower wage settlements and a lower probability of disagreement. Thus strike incidence is reduced. Furthermore, a recent strike may make a further one less or more likely, depending on the union's reservation wage and the precise way that market share evolves. This may help to explain some conflicting empirical results. Copyright 1996 by Royal Economic Society.