Optional Stopping and the Interpretation of The Bayes Factor

In their paper Why optional stopping is a problem for Bayesians, @deHeide:Grunwald:2020 critique the claim that those using Bayes factor can sample until there is sufficient evidence to support one or another model. de Heide and Grünwald's main message is that unless you believe your priors to govern the data-generating mechanism, optional stopping may distort inference. We show here that the distortions are not in inference but in interpretation. Their claim is about what happens when the analyst's models do not match the data generating models, that is, the Bayes factor for models not specified. Given that we never know the underlying data generation mechanism we ask researcher to interpret Bayes factors for what they are---the relative strength of evidence from data for two hypotheticals. We discuss how researchers should assess the robustness of their results by considering reasonable variation in model specification conditional on observed data rather than on hypothetical truths.

Comparative Study On Concentration Of Some Minerals Found In Garlic (Allium Sativum Linn ) Species Grown In Some African Countries

The concentrations of some minerals: K, Ca, P, Mg, Mn and Cu found in garlic species grown in Nigeria, Senegal and Chad were determined using Atomic Absorption Spectroscopy. The results showed that Nigerian garlic specie contained the highest concentration of phosphorus (1.29mg/L) and Copper (0.017mg/L). Calcium was found to be highest in Senegalese garlic specie (8.639 mg/L) with the Nigerian specie having the second-highest recorded value (6.930 mg/L). The highest values of Potassium, Magnesium and Manganese content were recorded for Chadian garlic (68.26mg/L), (51.60mg/L) and (0.212mg/L) respectively. The results obtained show that Senegalese garlic is rich in Calcium which is an essential mineral required for bone and teeth development, and also in the regulation of nervous excitability. Nigerian garlic is rich in Phosphorus which is a key component of the nucleic acids and also takes part in bone and teeth development; and Copper which plays an important part in blood clotting. The garlic specie from Chad is rich in Potassium, Magnesium and Manganese. Potassium plays an important role in maintaining pH balance and fluid distribution in the body; Magnesium in proper functioning of the muscles; Manganese is used in proper bone formation. Also from the results, there is reasonable variation in the concentration of the minerals, and this may be attributed to the types of soils on which the different garlic species were grown.

Predicting Centre-Dependent Spatial Density Functions of 3D Surface Anthropometry Data

A new, valuable but vast dataset will become available to the scientific and general public: the results of the CAESAR project (Civilian American and European Surface Anthropometry Resource). The concept of centre-dependent spatial density functions was introduced earlier to realise a major reduction in surface anthropometry scan data. Here the basic mathematics are described of centre-dependent vector shifts needed to arrive at these spatial density functions. Since as yet no real 3D scan data are available to us the concepts are tested with a Monte Carlo generation of ninetytwo models with a reasonable variation in eight anthropometric variables and discussed.