Many Labs 2: Investigating Variation in Replicability Across Samples and Settings

We conducted preregistered replications of 28 classic and contemporary published findings, with protocols that were peer reviewed in advance, to examine variation in effect magnitudes across samples and settings. Each protocol was administered to approximately half of 125 samples that comprised 15,305 participants from 36 countries and territories. Using the conventional criterion of statistical significance (p < .05), we found that 15 (54%) of the replications provided evidence of a statistically significant effect in the same direction as the original finding. With a strict significance criterion (p < .0001), 14 (50%) of the replications still provided such evidence, a reflection of the extremely highpowered design. Seven (25%) of the replications yielded effect sizes larger than the original ones, and 21 (75%) yielded effect sizes smaller than the original ones. The median comparable Cohen’s ds were 0.60 for the original findings and 0.15 for the replications. The effect sizes were small (< 0.20) in 16 of the replications (57%), and 9 effects (32%) were in the direction opposite the direction of the original effect. Across settings, the Q statistic indicated significant heterogeneity in 11 (39%) of the replication effects, and most of those were among the findings with the largest overall effect sizes; only 1 effect that was near zero in the aggregate showed significant heterogeneity according to this measure. Only 1 effect had a tau value greater than .20, an indication of moderate heterogeneity. Eight others had tau values near or slightly above .10, an indication of slight heterogeneity. Moderation tests indicated that very little heterogeneity was attributable to the order in which the tasks were performed or whether the tasks were administered in lab versus online. Exploratory comparisons revealed little heterogeneity between Western, educated, industrialized, rich, and democratic (WEIRD) cultures and less WEIRD cultures (i.e., cultures with relatively high and low WEIRDness scores, respectively). Cumulatively, variability in the observed effect sizes was attributable more to the effect being studied than to the sample or setting in which it was studied.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Instituto de Investigaciones Psicológicas (IIP

Replanting/underplanting strategy for old coconut plantations in Papua New Guinea

In most producing countries, the population of coconut palms is growing old, and ways of replacing them are rarely implemented to ensure that production is maintained and the future of the industry and its profitability are safeguarded. Rehabilitating/replanting coconut plantations and adopting appropriate intercropping systems is one of the main challenges to be taken up for the future of coconut in the Asia-Pacific region. The example of Papua New Guinea (PNG) reveals one of the lowest yields per hectare among the countries in the Asia-Pacific zone. Almost 106,000 ha were planted between 1910 and 1940, amounting to around 40% of the current coconut plantings, hence 80 to 100,000 ha can be expected to disappear in the next twenty years. Faced with this forecast, the PNG Cocoa and Coconut Research Institute (PNG CCRI) launched several operations, beginning with the creation of a coconut research centre on the PNG mainland: examination of a replanting strategy for old coconut plantings, based on hybrid planting material, distribution of improved planting material through the creation of a seed garden, and development of a system for controlling pest populations in high-risk zones. The experiments set up at the station are designed to optimize the felling date for old coconut palms, by measuring the effects of competition with the underplanted hybrids, and to determine from an economic point of view the best strategy to be applied for implementing rehabilitation and/or replanting programmes in old coconut plantings. This paper describes the results of these operations

Le complexe Scapanes-Thynchophorus, principal problème entomologique du cocotier en Papouasie-Nouvelle-Guinée

National audienc

Trapping and disruption of the mating activ of Scapanes australis using live male as bait in Papua New Guinea

International audienc

New aspects of the biology of the Melanesian rhinoceros beetle Scapanes australis (Col., Dynastidae) and evidence for field attraction to males

Scapanes australis is a major coconut pest, endemic in Papua New Guinea. Early in the night, males placed singly into artificial galleries made in young coconut palms exhibited a sex specific calling behaviour for 0 to 1.5 h. Coming to the gallery entrance, they raised the abdomen and the hind legs, the head lowered inside the gallery, and emitted a liquid secretion, rhythmically smeared by crossing the legs. Females, which did not behave so, were very mobile. The adult flying period coincided with the male calling behaviour. In field assays with caged insects on coconut palms, attraction of both sexes to males was evidenced when they were calling. Males fought for gallery possession at a male arrival. No aggression but mating was observed with arriving females, which proved not to have developed oocytes. The strong male attraction was confirmed using automatic traps, baited with one live male in a sugarcane piece. Males were assumed to release an aggregation pheromone. Further studies are underway to identify the putative pheromone

Many Labs 2: Investigating Variation in Replicability Across Samples and Settings

We conducted preregistered replications of 28 classic and contemporary published findings, with protocols that were peer reviewed in advance, to examine variation in effect magnitudes across samples and settings. Each protocol was administered to approximately half of 125 samples that comprised 15,305 participants from 36 countries and territories. Using the conventional criterion of statistical significance (p &lt; .05), we found that 15 (54%) of the replications provided evidence of a statistically significant effect in the same direction as the original finding. With a strict significance criterion (p &lt; .0001), 14 (50%) of the replications still provided such evidence, a reflection of the extremely high-powered design. Seven (25%) of the replications yielded effect sizes larger than the original ones, and 21 (75%) yielded effect sizes smaller than the original ones. The median comparable Cohen’s ds were 0.60 for the original findings and 0.15 for the replications. The effect sizes were small (&lt; 0.20) in 16 of the replications (57%), and 9 effects (32%) were in the direction opposite the direction of the original effect. Across settings, the Q statistic indicated significant heterogeneity in 11 (39%) of the replication effects, and most of those were among the findings with the largest overall effect sizes; only 1 effect that was near zero in the aggregate showed significant heterogeneity according to this measure. Only 1 effect had a tau value greater than .20, an indication of moderate heterogeneity. Eight others had tau values near or slightly above .10, an indication of slight heterogeneity. Moderation tests indicated that very little heterogeneity was attributable to the order in which the tasks were performed or whether the tasks were administered in lab versus online. Exploratory comparisons revealed little heterogeneity between Western, educated, industrialized, rich, and democratic (WEIRD) cultures and less WEIRD cultures (i.e., cultures with relatively high and low WEIRDness scores, respectively). Cumulatively, variability in the observed effect sizes was attributable more to the effect being studied than to the sample or setting in which it was studied

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Many Labs 2: Investigating Variation in Replicability Across Sample and Setting

We conducted preregistered replications of 28 classic and contemporary published findings with protocols that were peer reviewed in advance to examine variation in effect magnitudes across sample and setting. Each protocol was administered to approximately half of 125 samples and 15,305 total participants from 36 countries and territories. Using conventional statistical significance (p &lt; .05), fifteen (54%) of the replications provided evidence in the same direction and statistically significant as the original finding. With a strict significance criterion (p &lt; .0001), fourteen (50%) provide such evidence reflecting the extremely high powered design. Seven (25%) of the replications had effect sizes larger than the original finding and 21 (75%) had effect sizes smaller than the original finding. The median comparable Cohen’s d effect sizes for original findings was 0.60 and for replications was 0.15. Sixteen replications (57%) had small effect sizes (&lt; .20) and 9 (32%) were in the opposite direction from the original finding. Across settings, 11 (39%) showed significant heterogeneity using the Q statistic and most of those were among the findings eliciting the largest overall effect sizes; only one effect that was near zero in the aggregate showed significant heterogeneity. Only one effect showed a Tau &gt; 0.20 indicating moderate heterogeneity. Nine others had a Tau near or slightly above 0.10 indicating slight heterogeneity. In moderation tests, very little heterogeneity was attributable to task order, administration in lab versus online, and exploratory WEIRD versus less WEIRD culture comparisons. Cumulatively, variability in observed effect sizes was more attributable to the effect being studied than the sample or setting in which it was studied