I need someone to complete my statistic psychology homework (SPSS)

Name(s): Alhanouf Alkhathamy________________________________

PSYC 290: RDA I

One-sample t-test Lab

You may complete this assignment in pairs. (Remember, a “pair” consists of exactly two people.) Be sure to write both your names on the assignment, or you will receive no credit.

Short Answer

1. What does a one-sample t-test measure, and how is it different from a z-test? (3 points)

A one sample t-test is used to compare the mean of a continuous variable in a specified sample against the mean of the same variable in the whole population. The one sample t-test differs from the z-test in that it uses the t-statistic and is applicable when the population standard deviation is unknown (sample standard deviation is approximated from the sample) and small samples size .. On the other hand, the z-test uses the normal distribution (it’s a parametric test) and applicable when the population standard deviation is known and sample size is large .

2. What is standard error? How is it different from standard deviation? (3 points)

The standard error is a measure of the statistical exactness of an estimate and measures how far the sample mean of the data is likely to be from the true mean of the population under study. It differs from the standard deviation since it is an inferential test (used to make inferences about the sample) while the standard deviation is a descriptive tool (used to describe the sample).

SPSS Problems

[Note: All inferences assume a 5% level of significance]

For SPSS problems, you will produce a full APA-style write-up of the results that clearly explains your hypothesis and findings. Be sure to proofread, and use proper APA format with respect to decimal places (2, except for p-values), italics, etc. Use the provided examples as a guide. Note: you should include a copy of your statistical output for all of the analyses.

1. The New Zealand Air Force needs to buy new helmets for their pilots, so they need to know if their pilots have larger heads than the average pilot. The average pilot’s head is 150.5 cm. The Air Force measured 18 recruits using metal calipers and then again using cardboard calipers. For the following questions, use the NZHelmet.sav dataset.

a. Were the NZ pilots’ heads larger than the average pilot’s head size when the metal calipers were used? Write out results using proper APA format as demonstrated in the guide. (8 points)

The study hypothesized that New Zealand pilot’s heads are larger than the average pilot. By using a one sample t-test, the study did not find significant difference between the New Zealand pilots and the general population t(17) = 1.87, p = 0.078, d = 0.44 when the metal calipers were used as a measurement tool. The sample data therefore fails to support the study hypothesis, that New Zealand pilots (n = 18) have larger heads (M = 152.94, SD = 5.54) than the average pilot (µ = 150.50).

b. Were the NZ pilots’ heads larger than the average pilot’s head size when the cardboard calipers were used? Write out results using proper APA format as demonstrated in the guide. (8 points)

The study hypothesized that New Zealand pilot’s heads are larger than the average pilot. By using a one sample t-test, the study did find a significant difference between the New Zealand pilots and the general population t(17) = 2.96, p = 0.009, d = 0.70 when the cardboard calipers were used as a measurement tool. The sample data therefore supports the study hypothesis, that New Zealand pilots (n = 18) have larger heads (M = 154.56, SD = 5.82) than the average pilot (µ = 150.50).

2. The average brain weight of adults is 1,345 grams, and the average head size is 3,675 cubic centimeters (cm3). A researcher collected the brain weights of 237 individuals in Indiana, PA to see if their brain weight was different from the average brain weight. Use the dataset HeadSize.sav for the following questions.

a. Were the brain weights of Indiana, PA residents different from the global average? Write out results using proper APA format as demonstrated in the guide. (8 points)

The study hypothesized that the brain weights of adult individuals in Indiana, PA differed from the global average brain weight of adult individuals. A one sample t-test found a significant difference between the brain weights of Indiana, PA residents t(236) = -7.95, p < 0.001, d = 0.52. The sample data therefore supports the study hypothesis, that brain weights of Indiana, PA residents (n = 237) is different from the global average (µ = 1345.00).

b. Were the head sizes of Indiana, PA residents different from the global average? Write out results using proper APA format as demonstrated in the guide. (8 points)

The study hypothesized that the head sizes of Indiana, PA residents were different from the global average of head sizes. A one sample t-test found did not find a significant difference between the brain weights of Indiana, PA residents t(236) = -1.73, p = 0.085, d = -11. The sample data therefore fails to support the study hypothesis, that brain weights of Indiana, PA residents (n = 237) is different from the global average (µ = 3675.00).

3. Researchers are interested in whether individuals who eat more than 1,000 additional calories a day than their bodies need over the course of 8 weeks gain any weight at all. The researchers collected the participants’ weight at the beginning of the 8 weeks and again at the end of the 8 weeks. Use the dataset Overeating.sav for the following questions.

a. Identify the null and research hypotheses. (2 points)

H0: Weight after – Weight before ≤ 0 (No weight gain). It was hypnotized that individual who eat more than 1,000 additional calories a day than their bodies need over the course of 8 weeks will gain weight.

H1: Weight after – Weight before > 0 (Weight gain). It was hypnotized that individual who eat more than 1,000 additional calories a day than their bodies need over the course of 8 weeks will see no difference in weight.

b. Did the participants experience a significant amount of weight gain? Write out results using proper APA format as demonstrated in the guide. (8 points)

The study hypothesized that individuals who eat more than 1000 additional calories a day than their bodies need will gain weight at the end of the 8 weeks. A one sample t-test was performed on the differences in the weight before and after, the study found a significant difference between the weight the individuals before and after t(15) = 10.84, p < 0.001, d = 8.36. Supporting the study hypothesis, individuals who ate more than 1,000 additional calories a day than their bodies needed (n = 16) weighed more after (M = 155.05, SD = 21.44) than before (M = 144.64, SD = 22.70).

Copy and paste all of your output to the end of this lab. Grading will be based on accurate analysis of the results and proper APA-style write-up. (2 points)

/* ====================================================

GET

FILE='E:\Clients\Chesaro\2019\makeupassignment\NZHelmet-2 (1).sav'.

DATASET NAME DataSet2 WINDOW=FRONT.

DATASET ACTIVATE DataSet2.

/* Q1 (a), (b)

T-TEST

/TESTVAL=150.5

/MISSING=ANALYSIS

/VARIABLES=Cardboard Metal

/CRITERIA=CI(.95).

T-Test

Notes
Output Created	14-MAR-2019 11:04:45
Comments
Input	Data	E:\Clients\Chesaro\2019\makeupassignment\NZHelmet-2 (1).sav
	Active Dataset	DataSet2
	Filter	<none>
	Weight	<none>
	Split File	<none>
	N of Rows in Working Data File	18
Missing Value Handling	Definition of Missing	User defined missing values are treated as missing.
	Cases Used	Statistics for each analysis are based on the cases with no missing or out-of-range data for any variable in the analysis.
Syntax	T-TEST /TESTVAL=150.5 /MISSING=ANALYSIS /VARIABLES=Cardboard Metal /CRITERIA=CI(.95).
Resources	Processor Time	00:00:00.03
	Elapsed Time	00:00:01.30

[DataSet2] E:\Clients\Chesaro\2019\makeupassignment\NZHelmet-2 (1).sav

One-Sample Statistics
	N	Mean	Std. Deviation	Std. Error Mean
Cardboard	18	154.56	5.823	1.373
Metal	18	152.94	5.536	1.305

One-Sample Test
	Test Value = 150.5
	t	df	Sig. (2-tailed)	Mean Difference	95% Confidence Interval of the Difference
					Lower	Upper
Cardboard	2.955	17	.009	4.056	1.16	6.95
Metal	1.873	17	.078	2.444	-.31	5.20

/* ====================================================

GET

FILE='E:\Clients\Chesaro\2019\makeupassignment\HeadSize (1).sav'.

DATASET NAME DataSet3 WINDOW=FRONT.

DATASET ACTIVATE DataSet3.

/* Q2 (a)

T-TEST

/TESTVAL=1345

/MISSING=ANALYSIS

/VARIABLES=BrainWeight

/CRITERIA=CI(.95).

T-Test

Notes
Output Created	14-MAR-2019 11:04:49
Comments
Input	Data	E:\Clients\Chesaro\2019\makeupassignment\HeadSize (1).sav
	Active Dataset	DataSet3
	Filter	<none>
	Weight	<none>
	Split File	<none>
	N of Rows in Working Data File	237
Missing Value Handling	Definition of Missing	User defined missing values are treated as missing.
	Cases Used	Statistics for each analysis are based on the cases with no missing or out-of-range data for any variable in the analysis.
Syntax	T-TEST /TESTVAL=1345 /MISSING=ANALYSIS /VARIABLES=BrainWeight /CRITERIA=CI(.95).
Resources	Processor Time	00:00:00.02
	Elapsed Time	00:00:00.02

[DataSet3] E:\Clients\Chesaro\2019\makeupassignment\HeadSize (1).sav

One-Sample Statistics
	N	Mean	Std. Deviation	Std. Error Mean
BrainWeight	237	1282.8734	120.34045	7.81695

One-Sample Test
	Test Value = 1345
	t	df	Sig. (2-tailed)	Mean Difference	95% Confidence Interval of the Difference
					Lower	Upper
BrainWeight	-7.948	236	.000	-62.12658	-77.5265	-46.7267

/* Q2 (b)

T-TEST

/TESTVAL=3675

/MISSING=ANALYSIS

/VARIABLES=HeadSize

/CRITERIA=CI(.95).

T-Test

Notes
Output Created	14-MAR-2019 11:04:49
Comments
Input	Data	E:\Clients\Chesaro\2019\makeupassignment\HeadSize (1).sav
	Active Dataset	DataSet3
	Filter	<none>
	Weight	<none>
	Split File	<none>
	N of Rows in Working Data File	237
Missing Value Handling	Definition of Missing	User defined missing values are treated as missing.
	Cases Used	Statistics for each analysis are based on the cases with no missing or out-of-range data for any variable in the analysis.
Syntax	T-TEST /TESTVAL=3675 /MISSING=ANALYSIS /VARIABLES=HeadSize /CRITERIA=CI(.95).
Resources	Processor Time	00:00:00.02
	Elapsed Time	00:00:00.02

[DataSet3] E:\Clients\Chesaro\2019\makeupassignment\HeadSize (1).sav

One-Sample Statistics
	N	Mean	Std. Deviation	Std. Error Mean
HeadSize	237	3633.9916	365.26142	23.72628

One-Sample Test
	Test Value = 3675
	t	df	Sig. (2-tailed)	Mean Difference	95% Confidence Interval of the Difference
					Lower	Upper
HeadSize	-1.728	236	.085	-41.00844	-87.7508	5.7339

/* ====================================================

GET

FILE='E:\Clients\Chesaro\2019\makeupassignment\Overeating (1).sav'.

DATASET NAME DataSet4 WINDOW=FRONT.

/* Q3 (b)

DATASET ACTIVATE DataSet4.

T-TEST

/TESTVAL=0

/MISSING=ANALYSIS

/VARIABLES=difference

/CRITERIA=CI(.95).

T-Test

Notes
Output Created	14-MAR-2019 11:04:49
Comments
Input	Data	E:\Clients\Chesaro\2019\makeupassignment\Overeating (1).sav
	Active Dataset	DataSet4
	Filter	<none>
	Weight	<none>
	Split File	<none>
	N of Rows in Working Data File	16
Missing Value Handling	Definition of Missing	User defined missing values are treated as missing.
	Cases Used	Statistics for each analysis are based on the cases with no missing or out-of-range data for any variable in the analysis.
Syntax	T-TEST /TESTVAL=0 /MISSING=ANALYSIS /VARIABLES=difference /CRITERIA=CI(.95).
Resources	Processor Time	00:00:00.02
	Elapsed Time	00:00:00.02

[DataSet4] E:\Clients\Chesaro\2019\makeupassignment\Overeating (1).sav

One-Sample Statistics
	N	Mean	Std. Deviation	Std. Error Mean
difference	16	10.4088	3.84064	.96016

One-Sample Test
	Test Value = 0
	t	df	Sig. (2-tailed)	Mean Difference	95% Confidence Interval of the Difference
					Lower	Upper
difference	10.841	15	.000	10.40875	8.3622	12.4553

/* for presenting the means

DATASET ACTIVATE DataSet4.

MEANS TABLES=Weightbefore Weightafter

/CELLS MEAN COUNT STDDEV.

Means

Notes
Output Created	14-MAR-2019 11:04:53
Comments
Input	Data	E:\Clients\Chesaro\2019\makeupassignment\Overeating (1).sav
	Active Dataset	DataSet4
	Filter	<none>
	Weight	<none>
	Split File	<none>
	N of Rows in Working Data File	16
Missing Value Handling	Definition of Missing	For each dependent variable in a table, user-defined missing values for the dependent and all grouping variables are treated as missing.
	Cases Used	Cases used for each table have no missing values in any independent variable, and not all dependent variables have missing values.
Syntax	MEANS TABLES=Weightbefore Weightafter /CELLS MEAN COUNT STDDEV.
Resources	Processor Time	00:00:00.02
	Elapsed Time	00:00:00.03

[DataSet4] E:\Clients\Chesaro\2019\makeupassignment\Overeating (1).sav

Case Processing Summary
	Cases
	Included	Excluded	Total
	N	Percent	N	Percent	N	Percent
Weightbefore	16	100.0%	0	0.0%	16	100.0%
Weightafter	16	100.0%	0	0.0%	16	100.0%

Report
	Weightbefore	Weightafter
Mean	144.6362	155.0450
N	16	16
Std. Deviation	22.70488	21.43806

Use difference instead of weight before and after

/* ====================================================.