I can`t open spv file in my SPSS. So look at table with item-total correlation. Have some items negative item-total correlation? Did you recode reverse score items?

did you calculate cronbach's alpha for all 10 items? you know that big five personality inventories consist of 5 different factors so you have to calculate alpha for each of those 5 factors (which in your case may consist of 2 items per factor).

additionally you may recode some items (depending on your inventory, some of them contain reversed coded items).

Cronbach's alpha is based on the average correlation among your items, so if that average is negative, then alpha will be negative.

The usual approach is to ensure that all your items are all scored in the same direction, but I'm not sure that makes sense when you believe there are five subscales. Is there any reason to believe that being higher on one dimension would lead you to be higher than another, or are these five factors supposed to be relatively independent?

It seems as if there are 2 items for each of the 5 subscales, so at a minimum you need to be sure that the items in each such subscale are scored in the same direction.

Overall, it sounds like you would be better using a Confirmatory Factor Analysis, that specified five separate factors with two indicators for each factor. If CFA is too complex, then you can run an Exploratory Factor Analysis to find out if there are indeed five factors with each items loading on one and only one factor (so-called "simple structure").

here is the reference of scale I have used to measure big five personality and I have reverse coded items as guided by author

Rammstedt, B., & John, O. P. (2007). Measuring personality in one minute or less: A 10-item short version of the Big Five Inventory in English and German. Journal of research in Personality, 41(1), 203-212.

and  Michal Hajdúk I am attaching doc file for output of reliability analysis

thanks

I looked at the correlation matrix in your output and the reason why you have such a low alpha is because you have low correlations across all the variables in your dataset. I suggest you go back and look at your raw data using Frequencies to make sure the coding is correct. (The most common source I've seen for problems like this is due how people coded their missing data, so be sure to check that.)

thanx sir I have very low missing data about 4.4% and replaced it with average values but facing same issues

sadia, as i assumed before: you shouldn't include all 10 items in the analysis. why do you do this? is there some special reason (do you want to get a general factor of personality?)? remember: you used a big five personality inventory, so there are FIVE dimensions (= factors) of personality measured with this inventory!

instead you should compute cronbach's alpha for each factor (1 factor = 2 items). and check whether there are reversed coded items - they have to be recoded first!

you cited your source (Rammstedt, B., & John, O. P. (2007)), every information on the five factors and the corresponding items should be in there...

(i should add: of course you have to do factor analysis before to see if you really have 5 factors - but that was not your question)

thanks a lot Manfred Hammerl your guidance removed my confusion but there is a a trouble that I have only 2 items for one personality factor due to this I am unable to improve my cronbach alpha vale as reliability analysis don't provide corrected item total correlation value

and second issue is that in results of factor analysis are not align with research literature

so I am in troubleeeeeeeee

It is very unusual for a scale with proven reliability to perform so poorly. I suggest you take two of the items that are supposed to measure the same concept and generate a scatter plot. That will show you whether the data are indeed random, or whether something is distorting the correlation. (Note that the systematical lack of correlation among the items would also explain why the factor analysis did not work.)

Here is a list of reversed items and spss syntax to recode:

To score the BFI, you’ll first need to reverse-score all negatively-keyed items:

Extraversion: 6, 21, 31

Agreeableness: 2, 12, 27, 37

Conscientiousness: 8, 18, 23, 43

Neuroticism: 9, 24, 34

Openness: 35, 41

To recode these items, you should subtract your score for all reverse-scored items from 6. For example, if you gave yourself a 5, compute 6 minus 5 and your recoded score is 1. That is, a score of 1 becomes 5, 2 becomes 4, 3 remains 3, 4 becomes 2, and 5 becomes 1.

Next, you will create scale scores by averaging the following items for each B5 domain (where R indicates using the reverse-scored item).

Extraversion: 1, 6R 11, 16, 21R, 26, 31R, 36

Agreeableness: 2R, 7, 12R, 17, 22, 27R, 32, 37R

Conscientiousness: 3, 8R, 13, 18R, 23R, 28, 33, 38, 43R

Neuroticism: 4, 9R, 14, 19, 24R, 29, 34R, 39

Openness: 5, 10, 15, 20, 25, 30, 35R, 40, 41R, 44

SPSS SYNTAX

*** REVERSED ITEMS

RECODE

  bfi2 bfi6 bfi8 bfi9 bfi12 bfi18 bfi21 bfi23 bfi24 bfi27 bfi31 bfi34 bfi35

  bfi37 bfi41 bfi43

  (1=5)  (2=4)  (3=3)  (4=2)  (5=1)  INTO  bfi2r bfi6r bfi8r bfi9r bfi12r bfi18r bfi21r bfi23r bfi24r

  bfi27r bfi31r bfi34r bfi35r bfi37r bfi41r bfi43r.

EXECUTE .

thanks  Gina you are right but you are providing me this for detail big five inventory and I am following 10 item scale 

Rammstedt, B., & John, O. P. (2007). Measuring personality in one minute or less: A 10-item short version of the Big Five Inventory in English and German. Journal of research in Personality, 41(1), 203-212.

and I have where 5 items are reverse coded and I have followed accordingly and following this issue

Sadia,

presumably the 10 items score five dimensions, as such Alpha is invalid, alpha only provides a valid result for unidimensional scales, and then only if there are a relatively small number of items.

your correlation matrix implies 10 individual items, there does not appear to be any two items sufficiently correlated to justify a scale, maybe items 10 & 7 are one of the dimensions?

I would check the reference provided by Paul as the poor outcome may have more to do with your sample than the measure.

Further, as it is an established measure you should be using confirmatory methods, not exploratory. so confirm the structure, or not, and then determine the reliability of the scales

I found very high minus reliability (-.83) on my students test analysis. They administered the test of 20 items of vocabulary , grammar and reading. Any suggestion in this case?

Sadia I am facing the same issue with academic resilience scale. i have reversed coded while entering data to spss given reversed values to all negative statements. if you have resolved the issue can you please help me?

sadia dear i am facing the same issue kindly guide if you resolved