answersLogoWhite

0

Suppose death from a specific type of cancer is a relatively rare event which is replicated over a very large number - the population. Then, the mortality numbers are likely to be distributed as Poisson variables rather than Normal or other distributions. The mean of each variable is equal to the relevant incidence rate: the number of deaths divided by the total population. The variances have the same value as the corresponding mean.

If the mean of two mortality rates are lx and ly, then the standardised difference,

z = (lx - ly)/sqrt(lx + ly), has a standard normal distribution.

An alternative method is to use a 2*3 contingency table, with combined figures used to estimate the expected numbers of deaths. Chi-square tests, including linear contrasts, can be used to test for significance of differences. However, since the mortality number may be small, the chi-square test statistics may not be robust.

User Avatar

Wiki User

11y ago

What else can I help you with?

Related Questions

How is Harry Potter 7 novel different from the movie?

The differences are not as significant as they were with the sixth film.


How do you compare two or more items?

When comparing two items or two objects, then look for the similarities (what is the same) and differences (what is different) between them.


What are the pros and cons of diary of a wimpy kid book?

Babe, you first need to know what you are comparing and contrasting. Comparing - comparing the two together (what are the similarities and differences) Contrasting - things that are different (what does 1 thing have that the other one doesn't) Hope this helps =)


Why is comparing and contrasting an important tool for readers?

Comparing and contrasting are ways of looking at things to determine how they are alike and how they are different. Comparing involves identifying similarities and/or differences (e.g., apples and oranges are both fruit) whereas contrasting involves comparing two or more objects or events in order to show their differences (e.g., an apple has a thin skin that we can eat; an orange has a thick skin that we cannot eat).


When comparing two different texts . This is considered a?

Comparing two different texts is considered a comparative analysis. This involves examining similarities and differences between the texts to identify key themes, ideas, or arguments. The goal is to provide a comprehensive evaluation of both texts.


How can you use statistical measures to compare populations?

There are different methods for comparing the mean, variance or standard error, distribution or other characteristics of populations. Without more specific information it is not possible to answer the question.


What procedure of comparing cultural similarities as well as differences among societies?

One common procedure for comparing cultural similarities and differences among societies is conducting cross-cultural studies. This involves examining various aspects of different cultures, such as beliefs, values, customs, and behaviors, to identify commonalities and differences. Researchers often use methods like surveys, interviews, and observations to gather data and analyze it to draw conclusions about cultural similarities and differences.


What is procedure of comparing cultural similarities as well as differences among societies called?

The procedure of comparing cultural similarities and differences among societies is called cross-cultural analysis. It involves studying various aspects of culture such as beliefs, values, norms, customs, language, and social institutions to identify similarities and differences between different societies. This analysis helps in understanding cultural diversity and its impact on societies.


What is the opposite of comparison?

The opposite would be contrast.(The term comparison would include both similarities and differences, but the specific term for comparing different characteristics is contrasting.)


Which of these is an example of contrasting?

Comparing two things that are different in order to highlight their differences, such as hot and cold, is an example of contrasting.


What type of research design studies the difference between groups of people?

A between-subjects design is used to study differences between groups of people. This design involves comparing the performance or outcomes of one group to another group under different conditions or treatments. It helps researchers determine if there are significant differences between the groups being studied.


What is the meaning of the science process comparing?

Comparing in the science process involves looking at different objects or phenomena to identify similarities and differences, leading to a better understanding of their properties or behaviors. It helps scientists draw conclusions, make predictions, or establish relationships between variables. Comparing is an essential step in scientific inquiry to analyze data and draw valid conclusions.