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multiple statistic exercises

1.) The following sample was obtained from a population with unknown parameters.

Scores: 6, 12, 0, 3, 4

Compute the sample mean and standard deviation. (Note that these are descriptive values that summarize the sample data).

Next part of question is to compute the estimated standard error for M. (Note that this is an inferential value that describes how accurately the sample mean represents the unknown population mean.)

2.) A psychologist would like to determine whether there is a relation between depression and aging. It is known that the general population averages µ = 40 on a standardized depression test.

The psychologist obtains a sample of n = 9 individuals who are all older than the age of 70. the depression scoresare 37,50,43, 41,39,45,49,44,48. on the basis of this sample can the psychologist conclude that depression for elderly people is significantly different from depression in the general population? Use a two-tailed test at the .05 level of significance. The instructions are to use SPSS to calculate the test statistic. Do the problem in hypothesis testing.

3.) On a standardized spatial skills task, normative data reveal that people typically get µ = 15 correct solutions. A spychologist test n = 7 individuals who have brain injuries in the right cerebral hemisphere. For the following data, determine whether or not right-hemisphere damage results in significantly reduced performance on the spatial skills task. Test with alpha set at .05 with one tail. The data are as follows: 12, 16, 9, 8 10, 17, 10 (This is to be done in hypothesis testing only).

4.) Standardized measures seem to indicate that the average level of anxiety had increased gradually over the past 50 years. in the 1950's the average score on the Child Manifest Anxiety Scale was u=15.1. a sample of n=16 of today's children produce a mean score of M=23.3 with SS=240.

a.) Based on the sample, make apoint estimate of the population mean anxiety score for today's children.

b.) Make a 90% confidence interval estimate of today's population mean.

c.) Interpret the confidence interval.

Solution Preview

Hi there,

Here are my answers:

For Question 1.) solution= u=5, and standard deviation is ...

Solution Summary

The solution provides explanations to solve mean, standard deviation, confidence interval and in addition, steps for t test are also provided.