Statistics Made Easy 2: Hypothesis Testing


After you have read the last post on Statistics Made Easy, it should have helped in some way in understanding your classes in statistics.  Note that these Statistics Made Easy posts are to supplement your knowledge in statistics and to pinpoint some of the main important things in statistics; it is in no way going to replace your textbooks in statistics for psychology.

For this post, it will cover the steps of hypothesis testing.  It is one thing that will definitely be mentioned in all statistics classes, and forms the basis for all inferential statistics.  I will cover inferential statistics in the next few Statistics Made Easy post.
One of the direct applications of hypothesis testing in psychology is the testing of the psychological theories when you start applying them to people or clients, and it is your job to test them out (non-statistically).

Steps:
1. Formulate your hypothesis/es
Come up with a null hypothesis and alternative hypothesis (Null = 0 = no difference/relationship/ etc.)

2. Select the appropriate test statistic and level of significance
Based on the type of conditions you are investigating (differences between 2 groups or more than 2 groups/relationship/regression), you can choose the respective tests. 
Level of significance (alpha) is usually chosen between .01, .05, and .10. The alpha of .05 is usually chosen in psychology research.

3. Compute the critical (cut-off) value
This critical value is usually derived from the respective tables (usually found in your textbooks, if you are doing this manually).  The critical value for the test-statistic is determined by the level of significance.  For example, with alpha of .05, you will have to use the critical z-value of 1.645.  The critical value is the value that divides the non-reject region from the reject region.  That meant that with an alpha of .05, you will have to reject the null hypothesis if your computed test-statistic (z-/t-value) is more/higher than the critical value of 1.645.

4. Compute the appropriate test-statistic and compare the computed test statistic with critical value
Here is where you have to calculate the test-statistic, and compare it to the critical value above, which will then make full sense in the next step that follows.

5. Interpret the decision
If the test-statistic is more than the critical value, then you will have to reject the null hypothesis, and accept the alternative hypothesis.  On the other hand, if the test-statistic is less/smaller than the critical value, then you will have failed to reject the null hypothesis, and hence reject the alternative hypothesis.
Advice: In all cases, it is quite impossible to accept the null hypothesis, unless there is truly no difference at all.

Here are the steps of hypothesis testing, which usually happens in quantitative research, although it might not be so explicitly stated when you reach more complex inferential statistics.  In life and work, we often do this as well, testing the educated guesses/hypotheses we have across people or situations and trying to figure out if we are able to believe something or if it is convincing enough.  In life, it's often done without the statistics, but the steps still apply pretty much in the same flow. 

SGPsychStud: Psychological Burnout - How does it feel like?


Stress..such a common experience.  Many students may experience this during their study terms, due to being overloaded with school work or personal life issues.  However, is the experience of psychological burnout common?  And how is stress and psychological burnout related?  I would say that burnout is common and it is highly related to stress, and it is quite common for students to face mental health issues (US article).

So what is psychological burnout?  According to HelpGuide.org, it is "a state of emotional, mental, and physical exhaustion caused by excessive and prolonged stress."  It usually started with you being overwhelmed with your experienced stress in school, work, or home.  As you get more overwhelmed with the stress over time,  you begin to lose the interest or motivation to continue with your work, or even on worst cases, this may lead to a major depressive episode.

There are actually quite a lot of reasons for why people experience burnout, and they are usually similar to those of stress and depression.  The symptoms of psychological burnout are actually quite similar to those of depression too, hence that is why it might be wrongly diagnosed as depression.  But burnout is not a clinical disorder.  The symptoms may include:
  • Feeling tired or lack of energy
  • Low mood and/or easily irritable or frustrated
  • Not feeling good about yourself
  • Amotivation in your usual (or even favourite) activities
  • Inability to concentrate and focus in class (especially for students) 
  • Others
This can help to anyone, no matter how young or old you are.  As students, it is very possible to happen for psychological burnout to hit you, especially when you are stressed to meet assignment due dates, last minute studying for exams, doing your projects, or even unknowingly mid-way of your study semesters and terms.  So what can you do about psychological burnout?

HelpGuide.org suggests "The Three R Approach":
  • Recognize – Watch for the warning signs of burnout
  • Reverse – Undo the damage by managing stress and seeking support
  • Resilience – Build your resilience to stress by taking care of your physical and emotional health
I would say "Prevention is better than cure", so one of the best things to do is to make sure that you have excellent time management skills.  This will ensure that things get done and prepared in time,  hence reducing your stress and your chances of getting a psychological burnout (See here for tips).