Question

In: Statistics and Probability

1a) Suppose that memory for unrelated words is distributed normally with a mean of µ =...

1a)

Suppose that memory for unrelated words is distributed normally with a mean of µ = 60 with a standard deviation of σ = 20. A random sample is selected from this population. After a treatment is administered to the individuals in the sample, a memory test that measures memory for unrelated words is administered, the sample mean is found to be M = 55. If the sample consists of n = 25 scores, can we conclude that the treatment has a significant effect? Use a two-tailed test with α=.01 The alternative hypothesis in words is:

Group of answer choices

The sample mean after treatment is not significantly different from the sample mean before treatment.

The population mean after treatment is not significantly different from the population mean before treatment.

The sample mean after treatment is significantly different from the sample mean before treatment

The population mean after treatment is significantly different from the population mean before treatment

The population mean after treatment is not significantly greater than the population mean after treatment

The population mean after treatment is significantly greater than the population mean before treatment

b)The null hypothesis in symbols is

c)The critical z values are

d)The z-score statistic is:

e) Your decision is

Group of answer choices

Fail to reject the null hypothesis and conclude that the treatment has a significant effect on memory scores

Fail to reject the null hypothesis and conclude that the treatment does not have a significant effect on memory scores

Reject the null hypothesis and conclude that the treatment has a significant effect on memory scores

Reject the null hypothesis and conclude that the treatment does not have a significant effect on memory scores

1b)

Suppose that memory for unrelated words is distributed normally with a mean of µ = 50. A random sample of n =36 is selected from this population. After a treatment is administered to the individuals in the sample, a memory test that measures memory for unrelated words is administered, the sample mean is found to be M = 52.

If the population standard deviation is σ = 18, can we conclude that the treatment has a significant effect? Use a two-tailed test with α=.05.

The null hypothesis in words is

Group of answer choices

The sample mean after treatment is not significantly different from the sample mean before treatment.

The population mean after treatment is not significantly different from the population mean before treatment

the sample mean after treatment is significantly different from the sample mean before treatment

The population mean after treatment is significantly different from the population mean before treatment

The population mean after treatment is significantly greater than the population mean before treatment

The sample mean after treatment is significantly greater than the sample mean before treatment

a.The alternative hypothesis in symbols is:

b.The critical z values are

c.The z-score statistic is:

Your decision is

Group of answer choices

Reject the null hypothesis and conclude that the treatment has a significant effect on memory

Reject the null hypothesis and conclude that the treatment does not have a significant effect on memory

Fail to reject the null hypothesis and conclude that the treatment has a significant effect on memory

Fail to reject the null hypothesis and conclude that the treatment does not have a significant effect on memory

e)Report the results in APA

Solutions

Expert Solution

hii...if you have any doubt please ask by comment. thanks..

orchestra answered 1 year ago

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