__Inferential
Statistics with Excel--Remember that t-scores are most often used since
population parameters required for use of z-scores are seldom known.__

__ __

**Excel 200****7
& 2010**

__Confidence Intervals__--Confidence
intervals using z are performed with the CONFIDENCE FUNCTION in Excel 2007
(CONFIDENCE.NORM FUNCTION in 2010) within the function
wizard (choose the __Formulas__ __Tab__ and select the __Insert Function__
option or select the __Function Wizard Tool__ from the formula bar).

Confidence intervals using t are performed with the Confidence Level
for the Mean item within the Descriptive Statistics option under the Data
Analysis Tool (choose the __Data Tab,__ select the __Analysis Group__ and
then select __Data Analysis)__ in Excel 2007 and 2010. You can also use
CONFIDENCE.T in 2010 if you do not want the other descriptive statistics.

In both instances what is returned to you is z(or t) multiplied by the standard error (s or s divided by the sqrt of n).

z*(s/sqrt of n) or t*(s/sqrt of n)--Your text book refers to this as the margin of error

You can then take the sample mean minus and the sample mean plus this value to get the two points defining the confidence interval.

__Z-Test for One Mean__--Use
the ZTEST function in Excel 2007 (Z.TEST in Excel 2010) within the function wizard. The function will guide you
through the argument and return to you a p-value. CAUTION: It tells you it is
returning a one-tailed p-value but this is not always the case. It returns the one-tailed p-value
for positive values of z. It returns 1 minus the one-tailed p-value for
negative values of z. This requires some careful attention in order to properly
draw your conclusions.

__T-Test for One Mean__--Excel
does not provide a function for this. The CD that came with your book may
provide
a macro for doing this test. Another option is to simply do some intermediate
calculations with Excel (standard deviations, means, etc.) and use these in the
formulas either in Excel or on your calculator. __In this class, we will first
calculate the sample mean and the standard error (s/sqrt of n). Using the
hypothesized ____
m, we will write a formula in a cell in
Excel that calculates t. __

__Then in Excel 2007, the TDIST function can be used to get the one or
two-tailed p-value for the single sample hypothesis test__.
The TDIST function requires 3 arguments in the parentheses.

TDIST(x,df,tails) Here x is the value of t calculated by the user via his or her own formula

(manually or in Excel), df=n-1, and tails is the type of test (1 or 2).

In Excel 2010, after calculating the t-score with your own formula, use the T.DIST.RT function for a one-tailed test. Use the T.DIST.2T function for a two-tailed test.

__2-Sample Matched Pairs
T-Test__-- In both Excel 2007 and 2010,
go to the __Data Tab__.
In the __Analysis Group__, select __Data Analysis__ and then pick __t-test: Paired Two Sample for Means__.
Fill in the dialog box using cell references for your data locations, also
highlight the labels for your data and check the labels box. Your
hypothesized mean difference will be 0.

__2-Sample T-Test Unequal
Variances__--In both Excel 2007 and
2010, go to the __Data Tab__.
In the __Analysis Group__, select __Data Analysis__ and then pick __t-test: Two Sample Assuming Unequal Variances__.
Fill in the dialog box using cell references for your data locations, also
highlight the labels for your data, and check the labels box. Your
hypothesized mean difference will be 0.__ __

__ __

**Excel 2003**

__Inferential
Statistics with Excel--Remember that t-scores are most often used since
population parameters required for use of z-scores are seldom known.__

__ __

__Confidence Intervals__--Confidence
intervals using z are performed with the CONFIDENCE FUNCTION within the function
wizard. Confidence intervals using t are performed with the Confidence Level
for the Mean item within the Descriptive Statistics option under the Data
Analysis Tool. In the first case you do not need the array of data to use the
function (you simply need the summary data requested in the function), however
in the latter case you must have the full array of data in order to use the
tool. In both instances what is returned to you is z(or t) multiplied by the
standard error
(s
or s divided by the sq.rt. of n).

z(s/sq rt of n) or t(s/sq rt of n)--Your text book refers to this as the margin of error

You can then take the sample mean minus and the sample mean plus this value to get the two points defining the confidence interval.

__Z-Test for One Mean__--Use
the ZTEST function within the function wizard. The function will guide you
through the argument and return to you a p-value. CAUTION: It tells you it is
returning a two-tailed p-value but it is not. It returns the one-tailed p-value
for positive values of z. It returns 1 minus the one-tailed p-value for
negative values of z. This requires some careful attention in order to properly
draw your conclusions.

__T-Test for One Mean__--Excel
does not provide a function for this. The CD that came with your book provides
a macro for doing this test. Another option is to simply do some intermediate
calculations with Excel (standard deviations, means, etc.) and use these in the
formulas either in Excel or on your calculator. __In this class, we will first
calculate the sample mean and the standard error (s/sq rt of n). Using the
hypothesized ____
m, we will write a formula in a cell in
Excel that calculates t. Then the TDIST function can be used to get the one or
two-tailed p-value for the single sample hypothesis test__.
The TDIST function requires 3 arguments in the parentheses.

TDIST(x,df,tails) Here x is the value of t calculated by the user via his or her own formula

(manually or in Excel), df=n-1, and tails is the type of test (1 or 2).

__2-Sample Matched Pairs
T-Test__--Select __Tools__/__Data
Analysis__ and then pick t-test: Paired Two Sample for Means.
Fill in the dialog box as requested.

__2-Sample T-Test Unequal
Variances__--Select __Tools__/__Data
Analysis__ and then pick t-test: Two Sample Assuming Unequal Variances.
Fill in the dialog box as requested.

__ __