Statistical Significance Tests – Are They Helpful?

Most of human history (actually pre-history) is uneventful. In its current form, our species has been around for something like 100,000 years. With only occasional and often transitory exceptions, we didn’t learn or create anything terribly impressive for 99 percent of that time. But in just the last few hundred years, human beings have accomplished a remarkable amount. Scientific and technological progress have accelerated and never stopped since modern scientific method was formulated in the first half of the 17th century, swiftly followed by the rise of the modern physical sciences.This recent rush of scientific and technological advance has been sustained for longer than any individual human lifetime, perhaps making it easy to forget that it is not inevitable. In fact, science has barely begun to find traction in the humanities and social sciences-including management theory, the decision sciences, and forecasting. We should be encouraged by the recent surge of activity in “evidence-based management.” At the same time, we should remain alert for practices that, while perhaps widely accepted, may impede the advance of scientific knowledge. I have long devoted myself to critically evaluating widely accepted theories and practices in the area of forecasting as applied to marketing and business in general-including the use of SWOT analysis, methods of choosing advertising agencies, use of portfolio planning methods for decision making, and reliance on game theory and focus groups. In this article, I assess tests of statistical significance and conclude that these tests harm scientific progress.Although popular in leading economics journals, psychology, and other areas, statistical significance is rarely used in the physical sciences. Schmidt and Hunter, after extensive study, concluded that “Statistical significance testing retards the growth of scientific knowledge; it never makes a scientific contribution.” There are various problems that arise with tests of statistical significance. These problems include the publication of faulty interpretations of statistical significance; misinterpretation by journal reviewers; and misinterpretation by readers even after training (such as in MBA programs). The development of science and cumulative knowledge is harmed because of a resulting bias against publishing papers that fail to reject the null hypothesis. Statistical significance testing distracts attention from key issues by leading people to think incorrectly that they have completed the analysis.How are researchers to report findings without use of tests of statistical significance? Better alternatives are available. To assess importance, I recommend using effect sizes or practical significance. To assess confidence, use prediction intervals; to assess replicability, use replications and extensions; and to assess generality, use meta-analyzes. In urging the discontinuation of the use of statistical significance, my focus is on the development of knowledge about forecasting. I speculate that statistical significance might help in certain areas, though currently there is no evidence for this. Until more evidence is found that supports statistical significance tests, they will be unnecessary even when properly done.

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5 Things to Consider When Choosing Engine Oil

When it comes to buying the right type of engine oil, you need to consider several important things. In this article, we have discussed 5 important things that can help you go for the right type of oil for your car engine. Choosing the wrong type of oil can have a negative impact on the performance of your car. Apart from this, it can also reduce the life of the engine. Therefore, it is extremely important to always use the right type of oil. Read on to find out more.

1. Car series and manufacturer

First of all, you should consider the make and model of your car. Today’s high-performance engines are designed for high efficiency. If you read your car manual, you will come to know about the right type of oil recommended by the manufacturer.

2. Driving environment

You should also consider your driving environment when making a choice. For instance, you may have a hot or cold climate. Similarly, road conditions may vary. You may have to drive on paved or unpaved roads on a regular basis.

Based on these factors, your car engine will have to tolerate different levels of strain. If you drive on unpaved roads, you will have to change engine oil more frequently. Some types of oils are designed to reduce the strain on your engine.

3. Types of oil

After you have considered the make and model of your car engine, you can go for either a mineral or synthetic oil. Each type has its own set of advantages and disadvantages. For example, synthetic oils cost more money but may last longer.

4. Viscosity grade

If you compare different products, you will find different codes and letters written on the labels. These numbers tell you about the viscosity grade and the resistance of the oil to flow. Now, this is an extremely important factor to consider after driving and climate conditions.

The letter W refers to winter. In other words, it tells you how the oil will perform in cold weather. The second number tells you about the flow of the oil at normal operating temperatures.

Normally, low viscosity oils are thinner and provide greater protection for your engine in cold weather. On the other hand, high viscosity oils offer greater protection in hot weather. Therefore, it is important to get familiar with the viscosity grade of the oil before making a purchase.

5. Oil standards

If you read the label closely, you will find letters and abbreviations, such as ILSAC, ACEA, and API. These acronyms tell you that the product can meet the requirements established by relevant authorities. You need to consider these specifications as they tell you a lot about the quality and performance of the oil.

If you take a closer look at the label, you will also find engine oil standards indicated by different acronyms, such as API, ACEA, ILSAC. This means that the product meets or exceeds the requirements set by these organizations. Specifications are important as they indicate the performance and quality of the oil.

Long story short, choosing the right type of engine oil is important if you want your car engine to work efficiently. Therefore, you may want to consider these important factors when looking for the right type of oil for your vehicle.

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How Does a Garbage Compacting Truck Work?

If you want to know how a garbage truck works, you are on the right page. In this article, we are going to take a look at the history of these vehicles. Without further ado, let’s get to the point.

Garwin Industries introduced the Load Packer for the first time in 1938. This vehicle became so popular that it brought a revolution in the industry of sanitation. As a matter of fact, it was the first compact garbage truck of its kind.

During those days, the carrying capacity of the vehicle was twice as much as before. The reason is that these trucks were able to compact the trash at high speed while driving across the city. In 15 years, there were a lot of garbage compactor trucks across many countries.

Due to the high demand for these vehicles, many manufacturers started the production of these vehicles. By the end of the 1960s, the world saw a lot of industrial standard compacting trucks. As the name suggests, these vehicles were designed to handle big projects as these trucks could compact trash a lot better than previous vehicles. In other words, they were able to handle 25% more load.

How does the Compactor Work?

Sanitation engineers load these trucks. The trash is put on a hopper, which is located at the back of the vehicle. The compacting mechanism works based on hydraulic cylinders. They transfer trash from the hopper to the body of the truck. This is the area where trash is compacted to save space. Once the trash is compacted, it is easy to handle for workers.

Since the trash compacting unit is located outside the vehicle body, trash does not fall out of the truck even if there is a lot of it. As soon as the truck is full, it is the responsibility of the driver to drive it to the dump.

The backside of the vehicle can be tilted up and the hydraulic cylinders can be used to move the panels. Afterward, the trash is dumped out.

Other Types of Garbage compacting Trucks

After the invention of garbage trucks, manufacturers introduced many variations of the vehicle. For example, they introduced a front loading truck. In these vehicles, the hopper was located in the front. The working principle of these vehicles is not different from conventional garbage compacting drugs.

Apart from this, you can find a lot of variations of recycling trucks. Some of these are side loaders while others have robotic arms that collect trash from streets. You can choose any type of garbage compacting truck based on your personal preferences. You may also want to discuss the matter with your employees to find out which vehicle suits them the best.

Long story short, this was a brief introduction to garbage compact trucks and the way they work. If you are looking for one or more of the units, we suggest that you consider the types described in this article. Apart from this, you may also want to do your research and ask around in order to make the best choice.

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