Exam 8: Parameter Estimates

A random sample of 41 children (all 5 years of age) was selected and given the Reading test of the WRAT (Wide Range Achievement Test). The sample mean was 20.57 and the estimated standard error of the mean was 1.98. Test whether the sample could be representative of a population whose mean was 23.52.

In order to predict whether a certain set of random sample scores could possibly be part of a given population, the researcher could use

If it is determined that there is no difference between the population mean being represented by the sample and the mean of the population at large, then

The estimated standard error of the mean takes on a negative value only when

When the confidence interval has a probability value of .99, then

If a researcher were to conduct 100 experiments, and in each case the null hypothesis were rejected at an alpha of .05, then

Multiplying the estimated standard error of the mean by 6 yields an approximation of

The estimated standard error of the mean can be calculated on the basis of the information

According to the text, the highest value that should be assigned to the alpha level is

The alpha level is typically set at either .95 or .99.

The single-sample t ratio may be used when all the parameter values are known rather than assumed.

In order to reach a confidence level of .95, then alpha must be set at

When the parameter mean is predicted to lie within a certain range of mean values, the technique employed is called

The average sentence (in months) for homicide is 227 (Gaines & Miller, 2003). A sample of inmates from a certain prison, all of whom having been convicted of homicide, was selected and their sentences calculated. The sentences follow: 200, 225, 197. 256, 300, 158, 220, 226, 230, 215, 237, 223, and 243. -Is this sample representative of the population?

The true standard deviation of the entire distribution of random sample means is defined as the standard error of the mean.

For the t ratio, the larger the sample size

A single-sample t ratio presents the difference between two means in units of

Random sampling helps to reduce bias.

The type 1 error cannot be committed when alpha is set at .05.

For the following set of sample scores, find the estimated standard error of the mean: 4, 3, 2, 2.