After a person has been diagnosed with schizophrenia in a family, the chance for a sibling to also be diagnosed with schizophrenia is 7 to 9 percent. If a parent has schizophrenia, the chance for a child to have the disorder is 10 to 15 percent. Over 250,000 diagnosed cases in Britain. 2  Rates of schizophrenia are generally similar from country to countryabout .5% to 1 percent of the population (there are variations-but the variance is difficult to track due to differing measuring standards in many countries, etc.).
View Full Document. Test Bias â A test bias is a systematic difference in the meaning of test scores amongst different groups. There are internal and external ways to identify test score bias. Test Fairness â This refers to how a test is used.
It does this by comparing the ratio of two variances. So, if the variances are equal, the ratio of the variances will be 1. All hypothesis testing is done under the assumption the null hypothesis is true. If the null hypothesis is true, then the F test-statistic given above can be simplified (dramatically). This ratio of sample variances will be test statistic used. If the null hypothesis is false, then we will reject the null hypothesis that the ratio was equal to 1 and our assumption that they were equal. There are several different F-tables. Each one has a different level of significance.