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# With alpha = .05 and df = 8, the critical values for a two-tailed t test are t = +-2.306. Assuming all other factors are held constant, if the df value were increased to df = 20, what would happen to the critical values for t? a. They would increase (move farther from zero). b. They would decrease (move closer to zero). c. They would stay the same. d. Not enough information to answer

Question
Normal distributions
asked 2021-01-06
With $$\displaystyle\alpha={.05}$$ and df = 8, the critical values for a two-tailed t test are $$\displaystyle{t}=\pm{2.306}$$. Assuming all other factors are held constant, if the df value were increased to df = 20, what would happen to the critical values for t?
a. They would increase (move farther from zero).
b. They would decrease (move closer to zero).
c. They would stay the same.
d. Not enough information to answer

## Answers (1)

2021-01-07
Step 1
Density curves of the t distribution are similar in shape to the normal distribution curve. The t distributions have more observations in the tails and less in the center than the normal distributions. As the degree of freedom increases, the t-distribution approaches the standard normal distribution. The standard normal distribution has mean 0. Thus, if all the other factors are held constant, and the df value were increased to 20, the critical values for t would decrease and will get move closer to mean, i.e., will get close to zero.
Step 2
Correct option:
b.They would decrease (move closer to zero).

### Relevant Questions

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White - 1176
Hispanic - 378
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White - 67
Hispanic - 38
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White - 1243
Hispanic - 416
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Why is that?
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Think of it this way. If you went to a college that was 90% female and 10% male, then females would most likely have the highest percentage of A grades. They would also most likely have the highest percentage of B, C, D and F grades
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What is the kinetic energy of a 2 kg ball that travels a distance of 50 metersin 5 seconds?
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A chi-square value of 6.15 is calculated from data in a $$4x5$$ contingency table. Assuming $$\alpha=0.05$$, identify the critical value.
26.217
31.410
21.026
16.919

asked 2021-05-04

When a gas is taken from a to c along the curved path in the figure (Figure 1) , the work done by the gas is W = -40 J and the heat added to the gas is Q = -140 J . Along path abc, the work done by the gas is W = -50 J . (That is, 50 J of work is done on the gas.)
I keep on missing Part D. The answer for part D is not -150,150,-155,108,105( was close but it said not quite check calculations)
Part A
What is Q for path abc?
Express your answer to two significant figures and include the appropriate units.
Part B
f Pc=1/2Pb, what is W for path cda?
Express your answer to two significant figures and include the appropriate units.
Part C
What is Q for path cda?
Express your answer to two significant figures and include the appropriate units.
Part D
What is Ua?Uc?
Express your answer to two significant figures and include the appropriate units.
Part E
If Ud?Uc=42J, what is Q for path da?
Express your answer to two significant figures and include the appropriate units.
...